What kind of HP do you get with the LT4 hot cam kit and heads, 58mm TB, Edelbrock manifold, Hooker headers, Borla Exhaust, 32 lb injectors and a slight increase in compression?
I've been told many things but I just made mods on my LT 1 engine. They included the LT4 hot cam kit with heads, gone from 52 mm TB to 58mm TB, went from 24 lb. injectors to 32 lb. injectors, Edelbrock manifold, Hooker headers, Borla exhaust and a slight bump up in stock compression. What kind of HP should I expect at the rear wheel? I was told by several Vette motor builders that the LT4 hot cam kit alone will pump out 430 HP at the crank and with the additional mods I will make well over 475 HP. What is the real HP I will make? Thanks in advance
5 Answers
its too hard to say really. i mean if you go get it dyno tuned you will probably be able to get 475hp+. without a dyno tune im guessing its right around 450 hp. nice mods though. exactly the same ones i would have done myself
My LT1 with your same mods, but with stock LT1 heads yielded about 350HP at the wheels on a Mustang dyno, and you'll find that a lot more than most people get. That was with a 6 speed and a 13lb flywheel, so driveline losses are likely 12-15% max, so that's about 400 at the crank. You are correct that adding the LT4 heads will get you to about 425HP range (crank). How much compression are you looking to add? I don't see the extra 45HP coming from that, nor the throttle body and injectors. If you ported the heads and went with a larger cam, maybe. Trouble is 475HP is a lot of power and it takes a bit of work and cash to get there with 350 cubic inches.
You started with 330 HP, I don't know what a slight bump in compression ratio is, but with 58mm@32lbs with a LT4 Hot cam kit you are probably close to your mark. With a FAST manifold and KOOKS headers and CORSA XTREAM exhaust and COMP cams roller rockers,you would easily make over 550 HP ! The AFR (Mongoose) heads are worth another 50 HP to total 600 HP on your little small block on premium gas only.
Awfully optimistic on those HP figures. In the real world, if you start with an LT4 engine, add Long tube headers, LT4 Hot cam, Port and match the heads and intake, 52 mm T-body (anything bigger than that is a waste), a good cat back system, and an electric WP, you'll get about 360-375 RWHP depending on how good your tuner is. That is all. The real power is going to come from the heads, and the LT1 castings do not stand up against the LT4 castings in any way. No way in hell you are going to make 550 hp with a hot cam, especially not a hot cam and stock lt-1 heads. You can't make that kind of power with a Hot cam and any kind of heads to be honest. You would need a 396 with a serious cam and some serious heads for that kind of power.
I agree with John the hp of a stock LT1 with stoc heads and a hot cam is probobly maxed out at 375 HP with stock block, pistons, heads I have a 1994 LT1 and expect to get 350 HP out of Cam, roller lifters and exaust. If I decide to go for mor I'll go with a complete engine with 450 HP. Crate engines are cheaper than going the rebuild and guessing at the specks and HP ratings.
