[Soggy_fries]

I've been thinking about building up an LTG and throw it into something. Maybe my current Camaro or maybe into my off roader. Question is, how much power can these blocks take? And what is the most power anyone has made in one these? For right now this is just a thought experiment but I am curious.

[Casimiro]

So far the word is a little over 600 hp has been made with forged internals.

[Casimiro]

Allen Mayo and ZZP

[V8Bully]

450 crank torque on some kind of ethanol mix seems to be pushing the stock block's reliability. These cars run pretty well at 330whp/380tq with a few mods. That makes the car pretty darn fun to drive since it is pretty light. Easily a mid to low 12 second car with driver mod.

These cars respond pretty well to running a bigger turbo but few companies have experimented. All the 6758/7163 cars I have seen make a really nice torque band but will require significant mods if you want to run any kind of real boost. They will also require a few fueling mods to make power reliably.

It would be interesting to see if anyone will eventually try to push the limits of the stock block with a much bigger turbo. Lots of EVO X guys run turbos upwards of 8474 and can make high 500 wheel with just some cams and lots of ethanol. However, the car loses a lot of driveability as it won't make any real power till past 5000 rpm. Nor will it exceed around 400 wheel torque.

[Casimiro]

https://www.dropbox.com/s/d546w6zlqp...0942.jpeg?dl=0

This was with a conservative tune.

[RedonBlackRS]

Originally Posted by Casimiro

https://www.dropbox.com/s/d546w6zlqp...0942.jpeg?dl=0

This was with a conservative tune.

Nice! What supporting mods do you have installed?

[Casimiro]

It has a ZZP forged bottom end, ATI balancer, stage 3 cams, valve springs, head studs, intercooler, aluminum radiator, larger throttle body, throttle body spacer ( for possibly a small wet shot of nitrous) , catted downpipe, E85 conversion and a Borg Warner 6758 EFR turbocharger

The car has a conservative Turbo Tim tune in it for now. On General G-MAX RS 255/40ZR17 on the rear and 225/45ZR -17 on the front, the car has been 12.012 @ 116.84

[Casimiro]

https://www.dropbox.com/s/4pnytyuiy3...44104.jpg?dl=0

[Soggy_fries]

Originally Posted by Casimiro

It has a ZZP forged bottom end, ATI balancer, stage 3 cams, valve springs, head studs, intercooler, aluminum radiator, larger throttle body, throttle body spacer ( for possibly a small wet shot of nitrous) , catted downpipe, E85 conversion and a Borg Warner 6758 EFR turbocharger

The car has a conservative Turbo Tim tune in it for now. On General G-MAX RS 255/40ZR17 on the rear and 225/45ZR -17 on the front, the car has been 12.012 @ 116.84

Not bad for a little 4 banger. Are you running an Auto or stick?

[Casimiro]

Auto

[95TA - The Beast]

Personally, I considered the "full build" that Casimiro did and for the 40-50hp difference it is a HUGE amount of cash to spend for everything that was done.

I mean certain items do NOTHING for power, such as the throttlebody, TB spacer and balancer.

Basically, it is well known that the bottom end stock internals have a 100% safe limit of 400hp/400tq. Can probably be pushed to 425-435hp/tq and still be "ok". But, it all comes down to how much of a chance you want to take. If you grenade a piston, it can take out the block and head, turbo, cats, etc, if it fully fractures. If it just burns a hole, or breaks a ring land, no biggie, as it can be just rebuilt with pistons and rods. It all comes down to monitoring the running and seeing how much knock you are getting and making sure the tune is done properly.

The big limiting factor on these cars is the transmissions (and transfer-case on the AWD models). They have a *real* limit of 400-425hp, anything more and you are looking at replacing it at some point, no questions asked. So Casimiro is looking at a trans at some point if he goes higher. For his current tune he is right at the limit, so as long as fluid is changed on an accelerated schedule it should live just fine.

And, yes I have heard certain models of certain transmissions used have "useable" pwoer levels to 460tq, but even at that they never expected that power level. Just look at any of the cars that HAVE levels like that and look at the transmissions/transfer-cases used and they are MUCH beefier totally different systems, not a warmed over and beefed up version of the same parts used in the lower powered cars.


Personally I was going to do forged internals and cams and all the rest, but if you consider that the last 40-50hp is almost 3x the price (not including labor, with labor more like 4-5x the price) of what you can get away with in regards to just a modified stock turbo (like the Big Wheel turbo from ZZP), a K&N filter in the stock airbox and a good tune you are looking at 320-330hp/tq right there and then an additional 20-30hp/tq from E85 added on and retuned, you are looking at 340-360hp/tq for a fraction of the money of the full build. Plus you are leaving a large margin of error for keeping the transmission (and transfer-case) alive long term.

I am personally on the latter-route. Now I have other cars that have much greater power, but I still want my CTS4 to be a fun car to drive. Personally I am expecting 330-340hp/tq without the E85. If I hit that amount of power I will be done and happy with it. If I am shy of that I will add in either E85 (it is available about 6-8 miles from here) or a methanol-injection setup and hit at least 340-350hp/tq.

I do think there is a lot being done that is wrong with tunes that end up causing problems. I also think there is little being done about changing the heat-range of the plugs being used once the power is bumped up, and that there is not enough of the "full tune" being modified to account for the increase of fuel and air. I have looked at the tuning tables for these motors and they are a TON of changes needing to be made for something as simple as a bigger turbo. I also have little faith in the majority of "tuners" because of the fact that you can see how many cars have had problems because of the tuning.

I personally have been tuning for over 24 years. I have NEVER had a customer come back with a broken motor from a tuning issue. I have had broken motors come back from "driver error", such as mis-shifting (v8s don't like to be revved to 8-9k RPM when they have a 7k RPM redline), the customer changing the nitrous shot without telling me after it was tuned for a given application (ie, they didn't change the fuel jet to compensate for the additional nitrous when they changed the nitrous jet) or they changed out pulleys on the supercharger and overboosted or modified the boost level without a retune... Stuff like that the tuner cannot be held accountable for. But sending out a car that has a ton of knock retard and saying it is "safe" is crazy.

Point is there is a ton of changes that affect the overall "useable power" more than just proper fueling and changing the timing tables. There are tons of global parameters that go into the calculations for applied torque, there are calculated torque tables, there are tons of "controls" on transitions and shifts and everything else, and if ALL of them are not tweaked for an increase in power, it is NOT a complete tune.

Again, after having looked into how to tune the LTG, it is NOT like any of the older LSx engines, or anything prior to that. It is a completely calculated "theoretical" engine management control system that expects everything to be calculated and matched up to be able to ascertain how the controller wants the engine to run. Quick "hacks" will do nothing but limit the reliability and overall function of the engine systems as a whole. And I cannot help but believe that a LOT of the tunes being done out there are just that, "hacks".

BTW, my background is as a systems engineer. Thus I have always taken a calculated approach to tuning engines. Earlier tuning systems were simple fuel and timing maps that were easily manipulated with a set of modifier tables that adjusted those maps. Even back then the MAJORITY of tunes were hacks (like modifying MAF calibration tables, which is insane considering a MAF is the only lab-grade piece of equipment on the engine and has a FIXED calibration), or only partial tunes with far too much left untouched which caused people to lose transmissions and have major drivability issues.

Later tuning systems have been moving more and more to "theoretical running" systems where the computer control anticipates how the motor runs, how much torque it makes at any given point and gives a level of "finesse" and "civility" to even the simplest of functions (like throttle tip-in and tip-out for example, which have a VERY complex setup on the LTG, which is compensated for by boost level, barometric air pressure, throttle position, engine speed, vehicle speed, anticipated torque applied, braking input and engine and air temperature).

Basically engines are no longer looked at as separate systems, as they are now part of a complete powertrain that includes power to each wheel, power generation, transfer through the transmission, shifting and transfer to the axles, braking systems and ride control and handling.

The probability of "screwing up the balance" of all the above is much greater than "getting it right" and having everything work in balance. In other words, making it generate the power it should is not just about the sum of the parts used, but it is accomplished by making the systems that use that power be able to anticipate the power available and be able to apply it appropriately. Every step of that is a set of complex changes, and I HIGHLY doubt many tuners are "going there" to do a complete tune.

[V8Bully]

This is why you get a proper tuner...Gen 5 GDI engines all use the same torque management style ecu. It's really not as scary as your making it sound, it was designed to make the car run more efficiently. Have you added a bigger turbo? On a properly tuned car, not much really changes other than WGDC. You may have to scale out the tables since the stock mapping won't accurate for the operating range. Bigger turbos will normally make less torque down low and more up top, so you don't really play with the driver demand if you scaled everything properly.

Also, part of getting it right is building the engine with the right parts. Even if they don't increase power, a good balancer will reduce engine vibrations and also has a safety factor involved when tracking the car.

[95TA - The Beast]

Big problem with ATI balancers is they degrade over time. They are a true "race part" that gets replaced when they expire.

Race parts only parts don't belong on a street car... One simple reason is when they sell that car, whomever buys it won't know about the balancer and if it falls apart then you have one hell of a problem. Happened on a buddy that bought a Z28 that was "built". 6 months later the long-expired balancer fell apart and trashed a whole ton of stuff.

Plus a new balancer is only needed if they changed the harmonics of the engine... Nothing they did would have done that... Only boring/stroking does that enough to warrant a better balancer. I can gurantee that a better balancer doesn't add anything and won't help anything on a stock bore/stroke motor. Now, if they went with neutral balanced balancer shafts and a "fixed" bottom end that was rebalanced, then an aftermarket dampner is most certainly warranted. But his build never mentioned that stuff, so you can assume he has stock crank and balance shafts, thus nothing more than a stock balancer is needed.

Sorry, too much snake-oil is tossed around on high performance stuff and only once you start maxing power out does it come into play. Especially the throttle-body "mod". What a joke, as a larger throttlebody ONLY comes into play once the throttlebody becomes a restriction and on a forced induction engine, it most certainly is not!

Again, people talk about "feel" and all the placebo stuff, when you can retune the ecu to give you the same "feel" with a totally stock throttlebody considering it is a computer controlled unit with no cable actuator.

Even teh whole "cold air kits" that are sold... Stock it is a "cold air" setup. All you have to do is do the math on how much of a restriction the stock snorkel system is. Most people don't realize that the stock setup is fine up over 400hp, probably close to 450hp.

The ONLY reason for a cold-air kit is for more turbo whine. PERIOD!

Again, when I tlak about power and supporting mods I am talking about actual power, not perceived stuff. I am talking about stuff that makes sense once you calculate it out.

And, no, I am not overstating how complex the tuning setups are. Anyone that wants to minimize it doesn't know what they are talking about. There are literally DOZENS of tables that need to be modified if you go with a bigger turbo. If you aren't making all those changes, it is a "hack". If you go with different cams, just about EVERY table in the engine management needs to be modified that deals with temps, fueling, torque, spark, etc, etc, with a healthy number of other tables dealing with torque and transmission settings. Again, if not then it is a "hack".

Oh, and I have RARELY seen a Gen 5 engine tune that isn't a hacked in place tune. Once again, VERY few actually spend the time and money to get EVERYTHING right, and in a tune if everything is not 100% done properly, it is not right.

[95TA - The Beast]

Oh, I forgot to mention, that to prove out why so many tunes are "hacks" is because the way the system is designed, it can anticipate just about every condition it will run into, including spark knock, and it can "dance on the edge" and not blow up because of how well controlled things are.

For anyone that toasted their engine, outside of running nitrous (which I have really only heard of one or two LTGs blowing up under those conditions), there is ZERO possibility the rest of the boosted engines had problems unless the tune was at fault. Again, if properly tuned to the max limits (barring "known issues" like weak stock piston batches) the only way a later LTG pops is because of an overly aggressive tune that is not done properly. If done properly, it would not allow the condition that would cause the failure. (outside of a missed-shift on a manual, where you go for fourth and hit second and totally mechanically over-rev the engine, for example)

I have tuned massive supercharger and multi-stage nitrous setups making over 1500hp and you always go for safe over max. The only ones that want the absoloute max are those that don't earn their money (trust fund guys, guys in illicit businesses where money comes too easy, etc) and don't care if it blows, they just want the number/ET, bragging rights, etc... I only have had a handful of customers want what I refuse to give them and in every case, I walk, then find they found the guy to tune it the way they want and it ends up grenading... And guess who gets the bad rap, the guy that did what they want. For everyone else, they usually get more in the way of driveability, manners, control and features when it is done right, so I have almost never had someone come back and want something different. And on those rare couple of occasions that has happened, they end up going in a totally different direction to reach their goals since the way they wanted to do it wasn't enough.