[Ribak433]

Ok, so as i've stated in many of my prior posts. I'm oldschool. So forgive me if these seems as if it is a dumb question.
My understanding, is that typically when you supercharge a street driven vehicle. You would typically run 8.5:1 compression ratio or in that neighborhood. Running 11.5:1 would require race fuel along with many other modifications.
Can someone explain to me how you can simply buy a supercharger, bolt it on in a few hours time, and enjoy the additional 150hp plus without any major mods. Short of obviously tuning the vehicle. "assuming that is a requirement"

[Modshack]

All depends on the boost level. Most bolt-on chargers run 5-8psi which is pretty mild and can be handled safely with tuning (timing, Fuel delivery etc).

Engines designed for charging with lower compression levels can handle much higher boost levels. My old Audi would pull 25 psi reliably with minor tuning adjustments..

There are thousands of supercharger installs on LS3's and LT1's with no problems.
As long as you don't get to radical and tune appropriately here seem to be no issues..

[HumanWiki]

Believe DI changes the nature of the FI due to the gas charge being shot in to the cylinder directly and providing some slight cooling effect over prior methods. There's a post around here somewhere where I believe it was talked about by some more knowledgeable than I -- and there was other things about the rotating assembly being stronger, port designs, etc... (again, not an expert by ANY means on that..)

I'll see if I can find the link. I may have seen that over in a Corvette board about the LT1s though.

[laynlo15]

I think Wiki is correct about the Direct Injection. There are a couple members with Heartbeat Magnachargers with no issues that I know of, one has run 10.81@128 w/A8. The technology of today is new school and old school doesn't seem to mean anything with this new stuff. You are right that you would typically run a lower compression ratio with turbo's or superchargers since your adding boost to the cylinders. My SC G8GT was about 10.5 to 1 and I just ran 93 octane without issues.

[KMPrenger]

Lots of guys ran SC and turbos on the 5th gen V6 with its high compression ratio. They ran awesome (at least...the ones that actually had a decent tune...long story there) and not until guys were pushing those things well over 500+ HP did they need to lower the CR.

So no surprise here for me at least.

[Modshack]

Posted this in your other thread...No need to do it twice. Just clutters up the forum and you may not get the answers you are looking for. Be sure to track your posts so you don't miss responses......:

All depends on the boost level. Most bolt-on chargers run 5-8psi which is pretty mild and can be handled safely with tuning (timing, Fuel delivery etc).

Engines designed for charging with lower compression levels can handle much higher boost levels. My old Audi would pull 25 psi reliably with minor tuning adjustments..

There are thousands of supercharger installs on LS3's and LT1's with no problems.
As long as you don't get to radical and tune appropriately there seem to be no issues.

[6spdhyperblue]

between DI and chamber design you can run higher compression then in the past. In OEM form the LT4 from the z06 is running 10:1 with higher boost and low exhaust temps - and capability to live through a few bad tanks of gas

in the LT1 the piston tops were designed to assist the chamber design to insulate the combustion kernel and allowing it to propagate in a controlled manner. Also they looked to minimize any hot spots in the chamber as well.




here is the list that comes to mind when thinking about level of boost:
dynamic compression - includes cam specification
timing
flame propagation
thermal efficiency of cylinder head material
injection type/spraying location
hot spots

[doc7000]

Modern day engines do a better job of conrtolling cumbustion, this has allowed really high compression ratios to be used on pump gas. Mazda actually runs as high as 14:1 compression ratios on some of the 4 cylinder engines.

[DGthe3]

Please create only 1 thread per topic. Threads merged.

-DG

[Ribak433]

Originally Posted by Modshack

Posted this in your other thread...No need to do it twice. Just clutters up the forum and you may not get the answers you are looking for. Be sure to track your posts so you don't miss responses......:

All depends on the boost level. Most bolt-on chargers run 5-8psi which is pretty mild and can be handled safely with tuning (timing, Fuel delivery etc).

Engines designed for charging with lower compression levels can handle much higher boost levels. My old Audi would pull 25 psi reliably with minor tuning adjustments..

There are thousands of supercharger installs on LS3's and LT1's with no problems.
As long as you don't get to radical and tune appropriately there seem to be no issues.

Thanks for the slap on the hand Modshack. I figured I'd get slack for doing that. And you are right.
Only reason I did, is cuz those sections just don't get much traffic. As you can see, I posted there, and in a days time. Only you replied. I posted here and within a few hours got an abundance of response!
My bad.... Will follow rules next time!

[Ribak433]

Thanks for all the input guys, guess its hard to teach an ole dog new tricks! This new age stuff can be quite overwhelming to say the least!
Then...... A to Z
Now..... A to k to c to x back to k...... Grrrr! My simple mind cant hang!!!!

[Modshack]

Originally Posted by Ribak433

Thanks for the slap on the hand Modshack. !

Oh, no problem. Make sure you are getting notified of responses to your posts. Do this in the set-up area.(User CP). Also, if you click on
"New Posts" in the header you'll get all the latest conversations no matter what the subforum.

[Obsol3te]

A bunch of us mustang guys are throwing 10-12lbs of boost at our 11:1 motors just fine on pump gas. Kind of shocked im seeing people only running 5-6lbs of boost on your cars so far.(And no, im not a troll. Just trying to learn more about the newer generation camaro's)

[LesBaer]

Originally Posted by Obsol3te

A bunch of us mustang guys are throwing 10-12lbs of boost at our 11:1 motors just fine on pump gas. Kind of shocked im seeing people only running 5-6lbs of boost on your cars so far.(And no, im not a troll. Just trying to learn more about the newer generation camaro's)

I've never heard of a single person running on 5psi on a gen6. I don't even think that's possible to do. Actually I don't even know of really any other people (non-vendors) running a super charger than myself. I've heard of a few people that bought Pro Chargers, but I haven't heard much from them once their parts arrived. Maybe they're out enjoying their cars, or maybe there's more to their stories than we know...I really don't know.

All I can do is speak to what I've done with my car, which I drive every day. I'm running on 6psi and could go slightly higher on pump gas, but I don't need to. When I first modded my SS, I had the car dyno tested with just the American Racing full long tube system and I gained almost 20rwhp. Then add the Maggie (and a professional tune), which is so efficient that at its stock level of 6, I'm putting down basically the same power as the new ZL1 (estimated by adding 15-20% to rwhp for hp at the crank) . You have to remember, this is a completely new ECU. We don't have the same engine control module as the C7. Eventually people are going to figure out how to do the same things that are being done on the Z06 to improve fuel delivery. It's just very early in the game right now.

The thing is for me personally - even if I could go higher - I wouldn't. There are other mechanical differences between the ZL1, Z06 and the SS beyond just a boosted LT1 engine. Once you approach 130mph, you also start to notice the aerodynamic limitations we have vs. the C7. I don't drive at that speed, but can get there and beyond in the blink of an eye. I'm very happy with where my car is right now. It's a beast and it sounds incredible. I've gotten all the meat left on the bone without having to worry about snapping the bone. So far I've put about 2k miles on it since adding my mods and I haven't had any codes or mechanical issues. I'd like to keep it that way