[LesBaer]

Originally Posted by jessrayo

Thanks for the back-up. I'm really neglecting that Camaro5 board since I got this 2016. I'm planning on running the ZL1 at the Texas mile next month if I can get it to come together.



I'm definitely with you on being one of the first into the game with forced induction on a LT1 Camaro. I'm quite sure I'm the first non-shop owner to have turbos on a 2016. Mine is back in the shop getting a broken weld fixed right now. The first run at a new system always has some issues. I'm fine with that. Now AGP is machining bolt together parts rather than welding for any future kits....

I guess my whole point on this discussion of the LT4 kit is that the LT1 motor is much different than anything in the old Gen5 Camaro LS series. All of the LS motors could make a boatload of power on the dyno if you could get more air into the motor. Air was always what limited your power on a Gen5 LS motor. Yeah you had to change injectors to keep up but buying a bigger injector was pretty easy. Since this LT1 (and to a certain degree the LT4) came out very few builders are running out of air. And fuel upgrades on these direct injection motors are more complex and expensive than simply adding injectors. On the really crazy builds the fuel is not atomizing well due to the volume sprayed over such a short duration and the injectors are struggling to get the amount of fuel into the cylinder over a fraction of the time the old port injectors had to administer a pulse.

The second issue with the LT1 motor is it comes from the factory with 11.5 to 1 compression ratio. The closest thing GM has produced before this to a high compression V8 was the LS7 at 11 to 1. Generally more compression means more power and this new LT1 is extremely efficient with no boost. It is pretty close to being maximized on pump gas. And what that means to the aftermarket is as you put more air into the cylinder with forced induction you have to roll the timing back out of optimal efficiency range to prevent detonation. Yes you can get more air in the engine but because of the timing adjustment you have less efficiency. The more you boost it... the farther it falls out of the optimal range. You really are getting diminishing returns with more boost on a stock LT1. Conversely the LT4 has 10 to 1 compression ratio stock and can go up to about 15 pounds of boost before it even hits peak efficiency. If I change the bottom on my car I would not run the same compression pistons, I would reduce to at least 10.5.

That is my point on this LT4 supercharger kit thread. The LT4 supercharger is probably the most efficient blower you are going to be able to put on the stock LT1 motor. It can even handle fuel updates to over 700 whp. With the previous generation GM motors more air capacity was always useful and it was easy to build into it. This LT1 engine is not really that way. It has to be completely reworked to the tune of probably $20K at least to be able to use any more air capacity available from the larger FI systems.

I got some pretty expensive turbos on my 2016 thinking I was going to start out with 750+ whp but as we started working through the issues I describe above here I realized I was going to need a completely new bottom end to hit that kind of power numbers. I kind of think I'm with the majority of people that want to mod the car without completely rebuilding a perfectly good engine.

Sorry I'm still not seeing what makes it a better SC if the E-force and Hearbeat can create more power, run cooler and don't take the same hits at the top end as the LT4 SC. Callway, Jannetty, Redline, Lingefelter, etc., the list goes on - they all focus their SC builds off of similar, larger TVS2300 superchargers. I haven't come across anything, anywhere that puts the LT4 SC at the head of the class for any car, whether it's running the LT1 or LT4 engine. I appreciate your input and experience, but you're literally the only person that I've ever heard say that the LT4 is the most efficient SC for our cars.

I agree that the majority of people won't go beyond adding the blower and other bolt-ons, but if we're going to rationalize this by what most people do, how many people do you see picking the LT4 SC over the offerings available? Maybe I missed it, but I haven't seen a single person here add the LT4 to their Camaro. I even see more people with Pro Chargers than I do with LT4's and we both know the LT4 is probably more reliable even if it does come from a GM parts bin.

I'm not sure where you're getting $20k in re-work being needed to the motor either, that's insane.

[AGP Turbo]

E-force and Heartbeat can create more power, run cooler and don't take the same hits at the top end as the LT4 SC.

And Turbo and Centri's do that even better. Keep following that logic tree. And turbos do it without using 60-80hp to run. And turbos make more tq. 693wtq on Jess's car on stock LT1 pump, injectors, cam.

[Speedy1975]

Interesting discussion. I was surprised to learn the LT4 used a small 1.7L compressor.

I've been fooling with superchargers for quite a few years and what I've personally seen is larger displacement superchargers are able to produce more power at less boost which means cooler temps all around.

I have a 2.3L Magnuson on my Challenger. 9:1 comp motor, stroked from 5.7 to 6.0L and fully forged. I run the smallest pulley I can put on the blower and it makes 14.5 psi and 600ish RWHP and RWTQ. Runs 10.80s in the 1/4 mile at 128-130MPH with a 6 speed manual trans in the car. Friends that went to 2.9L blowers make the same power on 11-12psi. However, I also have friends that went full monty and got KB 4.0L blowers. I've never seen one of those work especially well as it takes 100 plus HP to turn the blower to begin with, so there is a point where it is too big.

I do agree that the stock motor can only handle so much and yes you can exceed that with the 1.7, 2.3, or upcoming 2.9L blower. However I would argue that you will make the same power with less boost and resulting cooler IATs using a larger unit up to a point before you hit diminishing returns of blower parasitic losses as mentioned above. From what I've seen the 2.3L has done VERY well. I saw a 2016 2SS with a Maggie on it at LSFest Sunday. It was running 10.90s at 128MPH with just the blower slapped on it at 7psi. Impressive.

I also think you're on point with the compression ratio if you rebuild the LT1. 11.5:1 is high for FI. I went the opposite end of the spectrum at 9:1 for my Challenger. If I had that to do over again I would have done 10.5 - 10.8 so I could make power with less boost and run cooler.

[BravoMyles]

Originally Posted by Speedy1975

Interesting discussion. I was surprised to learn the LT4 used a small 1.7L compressor.

I've been fooling with superchargers for quite a few years and what I've personally seen is larger displacement superchargers are able to produce more power at less boost which means cooler temps all around.

I have a 2.3L Magnuson on my Challenger. 9:1 comp motor, stroked from 5.7 to 6.0L and fully forged. I run the smallest pulley I can put on the blower and it makes 14.5 psi and 600ish RWHP and RWTQ. Runs 10.80s in the 1/4 mile at 128-130MPH with a 6 speed manual trans in the car. Friends that went to 2.9L blowers make the same power on 11-12psi. However, I also have friends that went full monty and got KB 4.0L blowers. I've never seen one of those work especially well as it takes 100 plus HP to turn the blower to begin with, so there is a point where it is too big.

I do agree that the stock motor can only handle so much and yes you can exceed that with the 1.7, 2.3, or upcoming 2.9L blower. However I would argue that you will make the same power with less boost and resulting cooler IATs using a larger unit up to a point before you hit diminishing returns of blower parasitic losses as mentioned above. From what I've seen the 2.3L has done VERY well. I saw a 2016 2SS with a Maggie on it at LSFest Sunday. It was running 10.90s at 128MPH with just the blower slapped on it at 7psi. Impressive.

I also think you're on point with the compression ratio if you rebuild the LT1. 11.5:1 is high for FI. I went the opposite end of the spectrum at 9:1 for my Challenger. If I had that to do over again I would have done 10.5 - 10.8 so I could make power with less boost and run cooler.

So do you think the 2.9L Whipple may be too large for a stock motor? I mean, they claim it'll push more than the others, but how much would the size effect it? Think it'll be one of those borderline ones that will perform much better with more mods to support it and push it past that parasitic loss?

[Speedy1975]

Originally Posted by BravoMyles

So do you think the 2.9L Whipple may be too large for a stock motor? I mean, they claim it'll push more than the others, but how much would the size effect it? Think it'll be one of those borderline ones that will perform much better with more mods to support it and push it past that parasitic loss?

We're talking about a mere .6L difference in displacement over the Magnuson and EForce, so no I do not think it will be too big. It is also a twin screw design where the TVS is a hybrid roots design. Similar technologies but they do have some unique differences. There's arguments that go on like oil filter debates on which is better. Bottom line I think all three will work well on the LT1 and would choose based on customer service, support, tuner employed, etc. I'm partial to Magnuson, but merely because the one on the Challenger has impressed me so much.

[BravoMyles]

Originally Posted by Speedy1975

We're talking about a mere .6L difference in displacement over the Magnuson and EForce, so no I do not think it will be too big. It is also a twin screw design where the TVS is a hybrid roots design. Similar technologies but they do have some unique differences. There's arguments that go on like oil filter debates on which is better. Bottom line I think all three will work well on the LT1 and would choose based on customer service, support, tuner employed, etc. I'm partial to Magnuson, but merely because the one on the Challenger has impressed me so much.

I see. I'm fairly new to the realm of considering a SC setup so I'm learning. Sounds like I'm up in the air between the Magnuson, Whipple, and potentially E-Force right now. Was considering Procharger but mine is a daily and I really like the low down torque from the other not centri ones.

[Speedy1975]

Originally Posted by BravoMyles

I see. I'm fairly new to the realm of considering a SC setup so I'm learning. Sounds like I'm up in the air between the Magnuson, Whipple, and potentially E-Force right now. Was considering Procharger but mine is a daily and I really like the low down torque from the other not centri ones.

I'm personally not a fan of centrifugal superchargers like Procharger.

I have a Magnuson on my 4Runner that I put on there 7 years ago and it's my poor weather driver. It's been flawless as well. To bolt on almost 200RWHP, you really can't go wrong with one of these superchargers. Way more bang for the buck that other solutions IMO.

[Atomic Ed]

The one thing that raised my eyebrows on the ADM/1.7L install was how quickly and hard the torque curve hit. Coming on that strong, that low in the RPMs got me to thinking how hard are the internals being hammered out of the hole? It makes sense on the LT4 because that is what the GM team is looking for, the driving experience, low end punch, day-to-day

It's been my experience that too much torque, too quick bends rods and shatters pistons. Smaller turbos are notorious for doing this if not tuned right. Maybe the LT1 can handle it, but maybe some torque limitation might be in order for a safety margin on this system....just a thought.

[AGP Turbo]

Time will tell but the LT1 pistons and rods seem at least as strong as the LS3's. We beat the heck out of stock LS3's at 800wtq with no problems. We will start playing Mythbusters shortly and see what we can do.

[BravoMyles]

Originally Posted by AGP Turbo

We will start playing Mythbusters shortly and see what we can do.

I love it, curious to see where this goes.

[BlackinBlack]

Originally Posted by Atomic Ed

The one thing that raised my eyebrows on the ADM/1.7L install was how quickly and hard the torque curve hit.

This was the point of the LT4 supercharger. It amazes me that the LT4 has a 10:1 AF ratio but that is important to the choices made included the smaller blower.

Little read about the motor.

http://media.chevrolet.com/media/us/...owerhouse.html

As someone daily driving a car with a LT4 I have to say I have never felt a car this strong down low. My 670+ HP Mustang with a Centrifugal pulled crazy up high but was lazy down low. My ZL1 was strong down low but you could still feel the motor come "into the boost". High boost turbo cars were the worse. The LT4 feels like a large NA motor and that was the point.

That being said the design is built to a certain limit. In the Z06 world you get much over 800 hp at the crank the LT4 blower comes off and a Procharger or turbos come on. No one and I mean no one is running a 2.3. (And there are kits that fit the car.) A few tried them but the power difference was so small it was not worth the money. Even the Callaway cars don't make much power over a modded stock blower car. The big thing is the cooling brick design issues that caused overheating when running WOT for extended times under high heat conditions. This was resolved in the 2017 model cars with the new taller lid and brick layout.

[BravoMyles]

Originally Posted by AGP Turbo

E-force and Heartbeat can create more power, run cooler and don't take the same hits at the top end as the LT4 SC.

And Turbo and Centri's do that even better. Keep following that logic tree. And turbos do it without using 60-80hp to run. And turbos make more tq. 693wtq on Jess's car on stock LT1 pump, injectors, cam.

So what's your thought on a Procharger build? Think it has more potential even in the long run? What about in DD applications?

[shrubby]

Originally Posted by Speedy1975

I have a 2.3L Magnuson on my Challenger. 9:1 comp motor, stroked from 5.7 to 6.0L and fully forged. I run the smallest pulley I can put on the blower and it makes 14.5 psi and 600ish RWHP and RWTQ. Runs 10.80s in the 1/4 mile at 128-130MPH with a 6 speed manual trans in the car. Friends that went to 2.9L blowers make the same power on 11-12psi. However, I also have friends that went full monty and got KB 4.0L blowers. I've never seen one of those work especially well as it takes 100 plus HP to turn the blower to begin with, so there is a point where it is too big.

So no issues with the 2.3 Maggie since install? That's encouraging. In another thread, I mentioned that I was going with the Maggie and headers and someone was telling me I'd have nothing but issues. In general. The implication was buy yourself a ZL1 instead and save yourself the hassle.

I seriously considered the LT4 conversion but I have no way to do it myself where I am at, and the only person I could find doing these was ADM. Unfortunately it would have cost me another 1400 to ship my car there and back and then what happens when I need something. Maggie seemed the next best choice based on reliability.

[shrubby]

Why aren't more shops offering the sort of thing ADM is? Or are they?