[JimGnitecki]

Jim G’s Magnuson TVS2650R Magnum LT1 Camaro Supercharger Experience at Davenport Motorsports!

Introduction

This posting is about my GREAT experience at Davenport Motorsports in Calgary, Alberta Canada the past couple of days, during which Davenport installed a Magnuson TVS2650R supercharger in my 2022 Camaro LT1.

My car had only 675 km = 419 miles on its odometer when I rolled into their parking lot. The supercharger, and the care and attention with which the Davenport team did the install and extensive testing, have utterly transformed the car.

I’ll cover in this posting:

- The Davenport reputation
- The Davenport facility
- The Davenport Leadership and Team
- How I was treated
- A detailed analysis of the before and after dyno chart that was generated for my car
- A discussion on how the 3557 foot elevation of the Davenport dyno affects the dyno results!
- What I discovered on the 229 km drive home
- My reaction to the entire Davenport - Magnuson experience

I realize that this forum, and particularly this Forced Induction subforum, is a hangout for the most experienced forum members, and their reaction to this posting might be a “been there done that many times” yawn, but I figure there are plenty of forum members who have not yet supercharged their car, and this posting might help them know:

- what to look for in a forced induction product
- what to look for in a shop in order to get a safe, reliable, and satisfying installation
- what the end result can be like!

For those wondering about my background and credentials to do a posting like this: I’m strong on automotive performance theory but weak on hands-on experience because I am not a mechanic by profession, but rather a degreed engineer whose career was in Information Technology contract project management, managing projects for Fortune 500 companies and government agencies.

I’m good at planning and managing projects, but don’t claim to be any good with the actual hands-on work done with harmonic balancer pullers, high pressure fuel injection systems, and AFR tables. Plus, my hands are way too big to ever succeed as a mechanic on modern tightly-packaged cars (Hey, my fingers are too fat to text on my iPhone without embarrassing spelling results).

So, here we go.



The Davenport reputation

I am fortunate enough to live just 2-1/2 hours from Davenport Motorsports, which is located in Calgary Alberta. Davenport is the largest volume Magnuson dealer in Canada, has been doing Magnuson installs for many years, and is highly experienced and well regarded. I had heard from many that the shop’s reputation here in Canada is first rate, and that I could count on it doing a Magnuson installation really well. And, I was told that the customer service level is VERY high. As you will see later in this posting, all the above is in reality a really big understatement. Davenport ended up exceeding my expectations by a LOT as we got into the project - and beyond.



The Davenport facility

The Davenport facility is impressive. This is not a leased, dark, crowded, or oily-floored converted warehouse like so many other performance shops are. This is a very large, high ceilinged, with spotless coated properly drained floors facility that is owned, not leased, by Davenport. It has equipment that is obviously high quality and appropriate for the work being done

NOTE: The photo upload would not place the photos where I intended. They all ended up at the bottom of the posting. But, they ARE there for you to see.

Here’s the exterior view you see as you drive up:

(Photo 1)

Notice the quality and value of the cars in queue for services:

(Photos 2 and 3)


I made a point of catching the Viper in a photo since one of my sons owns an early 2000s Viper!


Here is the showroom and hospitality coffee area:

(Photo 4)

Here is a cutway of an actual Magnuson supercharger (not a model used on the Camaro, but illustrative):

(Photo 5)

Here is a photo of a Magnuson trophy given to Davenport, showing the general rotor shape:

(Photo 6)

Here are 2 photos of the central workshop area (with Steve’s kind permission). Note the cleanliness, organization, ceiling height, quality of equipment, and caliber of vehicles being worked on:


(Photo 7)

(Photo 8)

Here are the entrances to the separate and enclosed machining and engine build areas:

(Photo 9)

There’s even an isolated car wash area on the way to the rear entrance / exit of the building.

Here’s a photo of the separate dyno room where the Dynojet dyno is built ifully nto the floor for improved safety for both the vehicle being tested and any people present:

(Photo 10)

This is a photo of my own Camaro’s engine compartment, right after the installation, tune installation, dyno testing, and very thorough road testing were completed:

(Photo 11)

Miraculously, this all fits under the Unmodified factory hood!

Because Steve and his team knew that I would be driving 229 km just to get the car back home, with the first 30 or 40 km being on high speed freeway with no safe place to pull over if there was any problem, they made sure that the dyno testing and road testing both were very thorough. I KNOW they were thorough because the odometer read about 50 km higher when I picked it up than when I dropped it off. And they did this without me having to ask. That gave me a lot of peace of mind.

Note in this next photo that the drive belt for the Magnuson supercharger is noteworthy for a couple of reasons:

(Photo 12)

First, it’s the higher quality “Green” belt, for an extra margin of safety.

Second, it is an 8-rib belt. Steve tells me that on some of their Magnuson installations, where the customer’s specified pulley size at the blower is smaller, they use a 10-rib for even more of a safety margin.

Third, this belt drives ONLY the supercharger. The engine’s front end accessory drive belt is a separate belt. This has multiple benefits:

It lowers the loading for BOTH belts, and therefor adds more margin of safety
It allows the tension control for each belt to be independent, which is good because the loadings are different
It allows the vehicle to continue to be driven should the blower belt start slipping or fail outright, because the accessory drive belt remains unaffected

This is a good example that illustrates how both Magnuson and Davenport, working together, take the conservative and safer path when there are choices to be made on cost, quality, and reliability.



The Davenport Leadership and Team

The shop CEO, Steve Eisenberg, is not just a businessman. He is a REAL car enthusiast and even a drag racer. His personal collection of cars and trucks over the years has included some noteworthy vehicles including a Ford Lightning, a twin turbo Blackwing CT6-V Cadillac, and of course a Camaro ZL1. You can easily see in speaking with Steve that his automotive interests are both deep and broad.

You can also see very early in a conversation with Steve how he is very sensitive to what clients need and want when they come to a shop to get performance improvements made to their vehicles. He quickly understands your individual comfort level with technical aspects and communicates at an appropriate level, and has a keen understanding of how current economic conditions (e.g. the current low value of the Canadian dollar versus the U.S. dollar) can dramatically sway a client’s actual budget for mods, and he works hard with his suppliers to minimize cost hits that many shops would simply pass on to their clients. We talked for a while about how the current simultaneous combination of weak Canadian dollar and inflationary pressures on the price of Magnuson superchargers are combining to crerate challenges for his shop, his suppliers, and his clients. Steve is the kind of guy you can trust to treat a client fairly and sensitively, and who makes certain that he and his team communicate absolutely honestly.

He and I found ourselves conversing at length, both in person and by email, because he had so much knowledge he was willing to share, and he is a great communicator. Fortunately I was able to return the favour in a very small way, as he currently has a supercharged SSR in the shop , and me being the author of the book “The SSR Experience”, I was able to highlight for him some of the improvement opportunities I had identified for that model over the years.

Steve’s son is also part of the leadership team. He is a quiet and very personable younger man whose serious demeanour shows how responsibly he has taken on the role of learning the business. He is already doing the bookkeeping for the business as well as building his technical knowledge and experience further. And he was kind enough to drop me at my hotel on Tuesday and pick me up the next day when the car was almost ready.

The shop team is very, very impressive. Not only do these guys do the work very professionally and reliably, they were very careful with my car, and they answered all my questions without hesitation. It didn’t matter who I spoke with; EVERYONE in the shop was polite, knowledgeable, sensitive to my concerns, and a capable, and willing, communicator.

An HP Tuner licensing problem showed up on the 2nd day of my visit, due to a recent and rapid change in the network system that stores and communicates the licensing records that created a glitch. That glitch initially prevented the system from recognizing my car’s licensing. Had this occurred at a less experienced shop, it could have made for a serious problem for me, as I was 229 km from home, staying a hotel, and the car obviously could not be driven with the supercharger installed but with the OEM tune still in place! Steve’s Calibrator and Steve worked together quickly and successfully to find a workaround that solved the problem within minutes versus days. I appreciate the years of experience that made this possible.

Another advantage to working with Davenport is that they actually keep superchargers in inventory, and work hard to always procure those superchargers (as noted earlier in this writeup) at the best possible delivered price. Being the largest volume dealer in Canada, they have clout with Magnuson, so their joint efforts together help out Canadian buyers like me.

I’ve already mentioned the conservative approach that both Davenport and Magnuson take, which protects their clients from some of the bad things that can happen when risky choices are made for cost, time, or convenience reasons. Steve was careful throughout our dealings to describe to me the protective measures that he recommended we take together to protect my vehicle. I appreciate that.

Steve also alerted me to the serious problems that GM is having with the AFM (V4 mode operation) system. That system is currently the subject of a class action lawsuit because it has done serious harm to many GM vehicles, including Camaros, Corvettes, Pickup trucks, and SUVs. Some brand new vehicles have had the AFM fail on the drive home from the GM dealership! Davenport routinely now shuts off the AFM via the supercharger tune. Again, an advantage of their broad experience.

Finally, it is important when shopping for a performance shop to know and understand what kind of work any specific shop does, LIKES to do, and is highly experienced at. This was a big factor in my decision to go with Davenport. Right here in Lethbridge there is a shop with a sterling reputation for performance engine and driveline work. That shop builds strong engines from the ground up in-house, does restomod work, can diagnose most engine or driveline issues, and is always full with high quality vehicles. The AVERAGE experience in that shop is over 40 years of experience. However, that shop’s focus is primarily on 1960s era muscle cars, and restoration projects, not supercharger kit installations on current model vehicles.

They quoted a lower price for the install work for my project, but they would have been the wrong choice for mY project because of their VERY differently focused experience and skill sets. Simple examples: They could not have gotten me as good a price on the supercharger as Davenport because they don’t do a lot of these kits, and they would not have been able to handle that licensing glitch nearly as quickly, if at all.



How I was treated

I’m sure you’ve figured out by now that I feel like I was treated about as well as anyone could possibly hope to be treated on a project like this one.

I was given a clear quote with a fixed price (because Davenport is a very experienced installer of this specific kit!). There were no surprise price add-ons. The overall price was both fair and consistent with the quality of the facility, experience of the team, the many precautions taken at all stages of the work and testing, the openness and honesty of the communication, and the obvious desire to produce a process and outcome that is sensitive to the client’s needs and wants, and targets the client’s complete satisfaction.

And, I was provided with a Dynojet dyno chart that showed me exactly how the installation of the Magnuson kit changed my car, from “baseline” to “final test”.

Beyond all that, Steve’s son personally dropped me off at my hotel on the first day, and personally picked me up when the work was almost done. How often does something like THAT happen at a performance shop?

Not due specifically to Davenport’s direct efforts, but they happen to be located beside a major freeway, that itself intersects within a kilometer or two with THE major freeway access to the city (Alberta Hwy 2 / Deerfoot Trail). They are also literally right beside Calgary International Airport. There are 5 good chain hotels located within about 4 kilometers of the shop for a client to stay at overnight. And, I happened to pick one of those hotels that turned out to be truly excellent in terms of service, on-site restaurant, and a really nice room at a modest price. And finally, the immediate access to freeways, even though in a highly populated city, enabled me to safely begin testing the performance of the car within a couple of minutes after leaving the shop.

All this created a 2-day adventure for me that could not possibly have gone better.

So, yes, I LIKE the way I was treated, by both Davenport and the Best Western Port O Call Hotel!



A detailed analysis of the before and after dyno chart that was generated for my car

I am going to right at the outset of this section of the posting say this:

The Davenport facility is located in Calgary, Alberta Canada, which is at an elevation of 3557 feet above sea level. Elevation above sea level strongly affects the performance of both naturally aspirated and supercharged engines, and affects supercharged engines much MORE than naturally aspirated engines.

Therefor, the dyno results we are about to review for my Camaro, done at this 3557 foot elevvation, are not going to be representative of the dyno results you or someone else gets at sea level or at any other elevation that is less radically high than 3557 feet. All other things being equal, my car would deliver higher corrected numbers at low elevations than you are going to see on this 3557 foot chart.

In addition, my car has the automatic transmission drivetrain. The results for a car with a manual transmission drivetrain would be higher because the manual drivetrain incurs lower overall driveline losses.

I say this now so that you realize that your focus should be on the DIFFERENCE between the baseline dyno results and the supercharged dyno results, not so much on their absolute values.

On the section that follows after this one, I will discuss the significance of the absolute results separately.

That being said, let’s now look at the difference between the baseline result and the supercharged results:


(see Photos 14 and 15 of the dyno chart)


The stock engine and automatic transmission driveline delivered 390 of the stock 455 crankshaft horsepower to the rear wheels.

That’s about 85% driveline efficiency.

This is a HUGE efficiency improvement over older automatic transmission drivelines. For example, my 2004 Chevy SSR automatic driveline only got about 77% of the engine’s crankshaft hp to the rear wheels.

So, the new technology 10-speed automatic is VERY efficient.

In fact, this automatic driveline is close to being as efficient as the also available manual transmission driveline, whose efficiency appears to be about 88%.

NOTE! All these transmission efficiency percentages are based on the assumption that all the dyno power numbers being compared are all fully and correctly corrected for ambient temperature, humidity, and air pressure, and all using SAE versus STD correction. However, large differences in altitude of the testing locations can sometimes give results not absolutely 100% accurate, given the current state of the art control capabilities. So, don’t take these efficiencies as “Gospel”.

Peak power at the rear axle (RWHP) increased by 42%, from 390 to 553 hp. that’s a 163 rwhp gain, and that is also a 42% gain.

That increased power peak occurs at 6380 rpm versus the stock engine’s peak at 5690 rpm.

And, with the supercharger, the power curve does not slope back down after hitting its peak, unlike the baseline curve which does start eroding very quickly after its peak. This shows that the supercharge ris fAR from running out of capacity.

Calculating back from this 553 rear wheel horsepower being 85% of the crankshaft power, it looks like the engine is now making about 650 crankshaft horsepower. So, in effect, the Magnuson kit allows a Camaro LT1 or SS owner to get the power level of a ZL1 without buying a ZL1.

CAUTION! Do not assume you are getting all the advantages of a ZL1 for less money than you would pay to buy a ZL1. The ZL1 has a much more robust fueling system and engine internals (e.g. forged pistons), and I think it also has some significant enhancements to its brakes, suspension, wheels and tires, and structure. And because of the superior fueling system and engine internals, the ZL1 can handle much more aggressive boost than an LT1 can safely take. But, if you never go to a track, and 650 crank horsepower is sufficient to satisfy your Testosterone level, or you already have an LT1, the Magnuson kit is a good deal.

The SMALLEST measured power gain was at 2500 rpm, where it was a 27% gain.

From 3000 rpm to 5500 rpm, the gain ranged between 32% and 35%.

Another useful metric when looking at dyno curves, is to calculate the “area under the curve”. This is very useful, because some engine mods, for example cam changes, can produce very high “peak” power, but can severely degrade power at other rpm points. A dyno curve with more area under the curve, versus one short high peak, will often enable its vehicle to out-accelerate a vehicle with the wild cam. This factor also gains importance when the number of available transmission gears is low, and loses some of its importance when the number of available transmission gears is high.

Also, an engine with a wider powerband is going to feel much better in non-aggressive driving, which is most of the time.

You can determine the are under the curve on a paper chart or image easily by simply “counting squares”, and then comparing the number of squares for the dyno curves being compared.

In the case of my Camaro, the supercharger increased the area under the curve by 36%.

So, in terms of AVERAGE improvement in power across the entire working rpm range, the supercharging made the engine about 36% more powerful. That’s pretty impressive, given that the actual boost level at the 3557 foot elevation is notably lower than the same car would show at a lower elevation.

This is a phenomenal power increase attained without stressing any of the OEM components significantly!



A discussion on how the 3557 foot elevation of the Davenport dyno affects the dyno results!

The previous section of this posting compared the baseline dyno results to the supercharged dyno results.

Now let’s examine the ABSOLUTE supercharging results on their own, given the radically high elevation they were obtained at.

Steve, himself a dragracer, has told me:

“I will notice the car will run much harder as the air cools down and get denser, the colder it is, the lower the perceived altitude let's say.

I tell people the easiest way to tell is to run the car in the hot afternoon, and then in the cool mornings, it’s a profound difference, and all to do with air density (our “corrected altitude”).

That is a fact that you can feel in the car, without any dyno needed.

In NHRA drag racing, they have correction for altitude in pre set classes. Back in the day the 9.9 second super comp cars would run 10.3 in Calgary (at 3557 feet) and 10.1 in Edmonton (at 2201 feet), so as they say its all in the altitude along with humidity, temp etc, - but that is what they would do to make things fair I guess.

My ford Lighting ran 13.7 in Calgary, and driving out to Mission raceway in lower mainland BC went 13.2 nothing changed on my end, and picked up almost 6 MPH. That is HP you cannot buy, - this was almost 20 years ago, and I believe the boost picked up like 1.5lbs (at the near sea level track)”.


So to summarize, engines produce more power at low elevations, and less power at high elevations. And, supercharged engines exaggerate the effect.

And taking Steve’s example of his supercharged Ford Lightning, where the quarter mile time was 13.7 seconds in Calgary and 13.2 on the coastal mainland, and the boost was 1.5 psi higher on the coast than in Calgary, we can make some important statements:

My car would dyno with higher numbers at a lower elevation than it dynoed in Calgary. So the 553 rwhp may be an understatement of the true rwhp the car can now make at more normal altitudes.

13.7 down to 13.2 seconds, and a 6 mh gain in trap seed, implies a fairly significant power increase for Steve’s Lightning at low elevation, not just a small one.

Steve told me that all Magnuson tunes assume low elevation operation, regardless of the actual physical environment in which the vehicle is actually used. This is of course in case the owner makes trips to lower elevations sometimes! I pointed out to Steve that if the engine of my supercharged car is making less power at high elevation, then it must also be using less fuel. So, there is now a larger safety margin in place on the capacity of my OEM low pressure and high pressure fuel systems. This is good. He advised me not to get greedy and have him put on a smaller pulley though! I DO prefer to keep the extra safety margin.

One more important comment on the dyno chart: Those of you with a sharp eye for detail, who actually examine “the fine print” on a dyno chart will note that the chart has been corrected to SAE standard ambient conditions like it is supposed to be to make it usefully comparable to other charts made at different geographic locations or simply at different times at the same dynoing location. This makes dyno charts truly comparable.

There are 2 different formulas used for this correction to standard conditions; SAE and STD. The SAE correction formula is viewed by professionals as highly preferable, as it corrects to much more realistic conditions than the STD formula. It almost always generates horsepower and torque values that are a few percent lower than STD numbers. Good performance shops use SAE correction, while shops that want to make their clients feel better about their car’s performance sometimes use the STD standard, and many clients don’t know the difference and feel better seeing a higher number.

Most of the time, for dyno runs made at reasonable elevations and normal temperatures, humidity, and air pressures, the correction factors tend to be small, most often 5% or below.

However, at very high elevations, or very high temperatures or particularly dry or particularly humid air, these factors can go pretty crazy.

In Calgary, they DO go VERY crazy. If you look at the bottom of the dyno chart for my car, you will see that the correction factor was 1.14 (i.e. the raw data is changed by 14%)! I was stunned by that when I saw it, because I’ve never before had a car dynoed at very high elevation. But Steve assured me that this is perfectly normal for Calgary. The correction factors seen by his team typically run from 12% to 18%, because of the elevation and the high summer temperatures.

Now for me, that makes the corrected numbers challengeable, because while the correction formulas are good, they inherently assume that an engine can and will to get the best power it can out of a given ambient environment, good or bad. But engines cannot necessarily do that. Some engines simply do not adapt well to adverse conditions. Simple example: That’s why engines still, with all our current technology, run better in cold weather than they do in hot weather, as Steve pointed out in the quote earlier in this posting. So, don’t get too hung up on the exactness of the numbers.



What I discovered on the 229 km drive home


On the 229 km trip home, the effect of the increased power was explosive.

Acceleration to 100 kph is super quick now, with the 10-speed automatic needing only one lightning fast shift before getting there. AND it shifts WAY faster than any driver can shift the manual transmission.

If you floor the throttle while cruising at 110 kph, the automatic downshifts lightning fast to about 5th or 6th gear, the rear tires try to break loose (Goodyear run flats don’t have the best traction) and are restrained by the traction control and stability systems, but the car’s front end comes way up on its suspension, the exhaust sound becomes apocalyptic, and the car screams forward at an acceleration rate that does NOT decline as the speed rises dramatically to levels not wise on normal public roads. (But Alberta prairie roads are mostly very straight, very wide 4-lanes with wide shoulders, and the pavement is very well maintained, The speed limits are mostly very conservatively set at 110 kph = 68 mph, but The police don’t hassle drivers unless they are doing something really stupid or dangerous to others. My biker friends from BC tell me they cross Alberta at 150 kph = over 90 mph)

On 2-lane roads, passing cars at 100kph is easy and fast: Just move to the left lane FIRST, then hit the throttle, the transmission shifts down in under 100 milliseconds, the front end rises up, the traction control kicks in, and the Camaro squirts past the car being passed in an instant. You literally better not make the mistake of hitting the throttle while still in the same lane as the car ahead of you, because you might hit it if you do. And passing in the rain would best be done with great caution in pressing that gas pedal.

The exhaust sound is notably amplified over stock, but there is no audible supercharger whine, as this supercharger is a high capacity one that is really designed for higher horsepower applications. At the current state of tune on my Camaro, it is loafing along at relatively low supercharger rpm, so there is no external supercharger whine.

The tune that Magnusun sent to Davenport turns off the troublesome “V4” feature which GM blew the design on, but on the 229 km trip back from Calgary to Lethbridge, the fuel mileage I got was 8.5 Liters / 100 km, which is 27.7 Miles / US Gallon, which is almost what I got going TO Calgary before the supercharger was installed, so the supercharger seems to have not affected the fuel mileage much. This is despite all the unnecessary "testing acceleration" I did on the way home which obviously burned extra gas. And, I think it is absolutely remarkable that my dream retirement hotrod car now delivers fuel mileage that is about the same as our daily driver, a 2022 Ford Maverick with a turbocharged 250 hp 2.0 Liter inline 4 Ecoboost engine.

And this is all being done on 91 octane gasoline, because that is the highest octane gas available in Lethbridge. But Shell Canada is slowly converting all its stations in Alberta from 91 octane premium to 93 octane premium. The car’s computer continuously tests how far it can advance the timing without getting detonation, and retards the timing (makes less power) when only 91 octane fuel is in the car. So once I have 93 octane gas, it’ll make a bit more power yet (on both the street and on the dyno).

I am VERY impressed with this supercharger kit. It transformed the overall car even way more than the lipstick red leather seats we had installed did.



My reaction to the entire Davenport - Magnuson experience

You take your pride and joy vehicle to a well run shop and leave it there a day and a half, YOU do NOTHING, and the car comes out with 36% more average horsepower across the rpm range, and 42% more peak power, and you need do NO tinkering to keep it that way (the Magnuson supercharger’s oil supply is even lifetime sealed once installed!).

The amount of money you pay is consequential but understandable, and arguably “low” when you compare the resulting power impact per dollar spent against other mods like headers, cams, cold air intakes, etc.

Heck, sign me up ANY day for a deal like this.

Jim G

[laynlo15]

I knew you'd be happy, my days with Magnuson and dealing with Davenport was always a great experience for me also. I'm glad you're happy because that's the most important thing. They are also the main inlet into Canada from the US for Magnuson. We could not sell to anyone else in Canada. There's so much potential now that you went to the 2650. Congrats on your build and being happy with the results. Great right up also

[JimGnitecki]

Originally Posted by laynlo15

I knew you'd be happy, my days with Magnuson and dealing with Davenport was always a great experience for me also. I'm glad you're happy because that's the most important thing. They are also the main inlet into Canada from the US for Magnuson. We could not sell to anyone else in Canada. There's so much potential now that you went to the 2650. Congrats on your build and being happy with the results. Great right up also

Thanks, Laynlo15. I have asked Steve at Davenport for 2 more things that were not documented for me yet:

- The AFR being added onto the dyno chart printout, so I can see its average value across the rpm range and its consistency

- The boost psi at the 3557 foot elevation in Calgary! (I wonder how low it actually is at that elevation with the Magnuson sea level tune)

[JimGnitecki]

I forgot to mention that the dyno run was done in 6th gear. It makes for a small loss in reported power, because 6th gear is not the 1 to 1 ratio and is in fact 28% stiffer than 7th in the 10-speed auto tranny, but 7th gear is just too high a speed for safety on the dyno, as you need to hit 186 mph in 7th to reach 6500 rpm, and that's too high to be safe for the Goodyear run flat tires.

Jim G

[JimGnitecki]

I just realized that the "dip" at about 6250 rpm is common to most Camaro 6.2L dyno charts, at least for supercharged ones.

In another thread here on the forum, at least a couple of forum members say that is somehow due to the oil pump solenoid turning on, and that the dip can sometimes be eliminated just by cooling the engine a bit and doing another dyno run.

Interesting.

Jim G

[laynlo15]

.
Here was mine from a couple weeks back, no dip. Not sure why yours did that, maybe the throttle closed, just not sure. I would ask them what they thought.

[SATINSTEEL1LE]

Maybe cat over temp stepping in.

[JimGnitecki]

Originally Posted by laynlo15

Attachment 1110213.
Here was mine from a couple weeks back, no dip. Not sure why yours did that, maybe the throttle closed, just not sure. I would ask them what they thought.

The current posting thread on "Dip" on this forum, started by Kerry, mentions a couple of times within it that the dip is caused by the oil pump solenoid clicking on, and that it seems to be related to engine temp, as it can be made to disappear by cooling the engine and doing another run. No better explanation on why the solenoid clicks on and what that does, but hopefully someone who knows the details can chime in.

Jim G

[laynlo15]

Beats me, haven't seen it in any logs on any of my Lt1s. No help here

[MartinLe]

As laynlo15 said, with the 2650, the sky is the limit - lot of fun coming your way. Love those red seats.

[JimGnitecki]

Originally Posted by MartinLe

As laynlo15 said, with the 2650, the sky is the limit - lot of fun coming your way. Love those red seats.

Yes, the ride home really surprised me at the magnitude of the difference in power. and yes, the most common reaction to the liptstick red seats is "Wow!"

The seat recovering was a service offered by my local dealer, through a partnering with a local upholstery shop, that buys the kits from Alea in The U.S. I was worried when we ordered the seats that the red colour would not be a close match for the existing OEM "Redline" trim on/in both the interior and exterior. I thought I might need to get the OEM knee pads and door inserts recovered. But, the Alea seat covers proved to be pretty much an exact colour match! The Parts lady at the dealership was blown away by the match and the overall impact when she saw it.

Jim G

[JimGnitecki]

It's always fun and educational to simulate the performance of a vehicle in my performance modeling software.

I've never before entered the specs for a car that makes 553 rwhp, because I've never before owned a car with that much power on tap.

But, today I entered the car's specs, and first the "before" dyno curve, and then the "supercharged" dyno curve.

Very interesting results.

The supercharged car gets to 60 mph only about .02" seconds quicker than the stock car. This is because I assume a 3500 rpm launch for both, and the OEM runflat tires basically have no traction with either power curve. Both cars are thus basically limited to the same maximum acceleration rate of 0.65 g on the way to 60 mph.

Of course, if I ever made the necessary suspension and tire changes to handle more power, that would change the 0 to 60 outcome a LOT, but I have no intention to do so, as I never go to either the dragstrip or the track.

But as the speed increases, things get dramatically different.

The supercharged car takes 1.3 seconds less to get to 100 mph.

While the stock car hits the end of the quarter doing 120 mph in 12.1 seconds, the supercharged car hits 120 mph in 9.6 seconds, and does it in 964 feet.

The supercharged car does the quarter mile in 11.5 seconds at 132 mph.

GM says that a ZL1 with the automatic driveline ran the quarter in 11.4 at 127 mph. So, my simulation is apparently good on the time, but optimistic on the speed. You might think that maybe my Magnuson 2650 equipped car makes more power than a ZL1, but I doubt it. I think my assumed coefficient of drag (0.35) is too good. The actual Cd might be a bit worse, but GM refuses to release what the actual Cd is. Probably because it really IS worse.

My simulation says the top speed of the stock car is 189 mph. GM says it is 180 mph for a non-1LE Coupe (the ILE coupe is 175 mph presumably because of the downforce equipment on it). BUT, GM says this is the top TRACK speed. It does not actually say this is the top speed on a clear flat road of sufficient length.

My simulation says that " sufficient length" of road for the stock car to hit top speed is at least 5 miles, so I'm reasonably sure that GM quoted a top speed from a track with a straightaway that is less than 5 miles. (How many tracks have a 5 mile absolute straightaway, and have that entire distance absolutely flat as well??)

GM says that the ZL1 without the extra drag of the 1LE kit hit a top TRACK speed of 198 mph. But again, I am reasonably sure that the track did not have a long enough straightaway. You'd need about 4 miles to get to the true top speed on the ZL1. The distance is so much shorter for the ZL1 than for the non-supercharged car for 2 reasons:

1. The supercharged car has a lot more power to get to much higher speeds sooner, and

2. The Cd, as I mentioned earlier, is probably even worse than the 0.35 I assumed, and a car with a bad Cd hits terminal velocity sooner.

My simulation says that the supercharged LT1 could hit 213 mph but would need 4 miles to get there, and again, I readily admit that the Cd I assumed was based on comparison with older Camaros and other similar cars (like the Mustang). If the Cd is even marginally worse in reality, the software will predict a significantly lower top speed. For example, if the REAL Cd is 0.38, the predicted top speed falls to 206 to 207 mph. Again, it would be nice if GM would just 'fess up the actual Cd.

Anyway, doing the simulations was fun.

Jim G

[JimGnitecki]

I just got another copy of the dyno chart from Steve at Davenport. In this one, he had his calibrator add the AFR to the chart.

The AFR looks pretty good.

Also, the calibrator reported that the boost peaked at 6.5 psi at 6400 rpm. Talk about conservative!

Jim G

[arpad_m]

Originally Posted by JimGnitecki

I just got another copy of the dyno chart from Steve at Davenport. In this one, he had his calibrator add the AFR to the chart.

The AFR looks pretty good.

Also, the calibrator reported that the boost peaked at 6.5 psi at 6400 rpm. Talk about conservative!

Jim G

Yeah, that mighty 2650 is half asleep at 6.5 psi

With that said, this isn't actually too conservative for an LT1 with the stock fuel system and bottom end, the max safe boost on my lowly 2300 is around 7-7.5 psi, your bigger blower is less of a restriction, so 6.5 figures (not sure about the default pulley size for the 2650, I assume it's the same as with the 2300).