TA Dreaming

I'm in the planning/dreaming stages of the engine build for my LT1 and am unsure of which way to go. I've got a lot to learn and research so I was hoping to get some direction from people with more experience than me.

The car is a 2nd gen and has a T56. It's a street car that I'm building to handle. I'm not going to race it and my goals are actually pretty modest, say mid 400s torque and hp to the wheels. What I want though is great throttle response and torque down low. I love the way a roots blown car drives and want to replicate that with my LT1. Obviously, I'm going to have to fabricate a lot of the pieces. I figure the piping for turbos is going to be easier than an intercooled intake manifold. But, can I get a turbo set up, single or twin, to perform in the manner I'm after? Would a centrifugal super charger be a better option than either turbos or a roots blower? Honestly not sure I want to deal with the constant noise from them but if it's the best option, I can learn to live with it if I intend to stay with the LT motor.

All opinions welcome even if it's just stroke it and call it good. I feel like I'm falling into that middle area where it's just out of the reach of a reliable and non race built stroker but possibly not worth the effort of making FI work for such modest power goals. Luckily, the build process is what I enjoy most though.

Thanks

Injuneer

You can make "mid 400s torque and hp to the wheels" through the T56 on an LT1 with a really good set of heads and a matching cam. Doing a 383 would make it even easier.

TA Dreaming

But what kind of power band? I want the car to pull hard from about 2000 rpms and up. The only built NA LT1s I have seen that hit those wheel numbers don't make it that low and are rather radical and expensive builds using the best of the best parts and built by the best people in the game. Have I missed the more straight forward builds that hit those numbers and at a lower rpm like I desire? I've been out of the game a while and have looked around but not extensively.

Thanks

Kevin Blown 95 TA

Like he said, a 383 would be a good street car with lots of torque down low if you chose the cam carefully. LT1 has a broad torque curve. A roots blower would too, but it is somewhat of a hassle on a LT1 since the heads are different from a earlier motor. You don't see many roots blown LT1s, but that is mostly because the engine on a 4th gen is half way under the windshield. And they heat soak. A turbo and centrifugal blower would make power in a higher rpm range and is harder to use that power on the street. You could do a basic centrifugal install at low boost and it would be a fun street car meeting your goals easily, but you are spending a good wad of cash to do it and most of them start making boost around 3300 or higher.

TA Dreaming

Thanks. The engine is now in my 79TA not that it really makes it any easier to put a roots blower on the engine itself though. You're right about power coming on hard at 3300 on the centrifugal blower. The cars I've ridden in have been fun and fast but just didn't make the power low enough for my driving style.

JakeRobb

Turbo: tons of low end torque that takes a moment to arrive when you mash the gas, but comes through like a wall when it hits.

Supercharger: with the right pulley and waste gate setup, you can have just as much torque down low, but it comes on linearly, without the wave you get with a turbo.

Pick whichever you like.

Or go NA. A well built 383 stroker will be plenty to meet the numbers you said.

shosovr

If your goal is mid 400 RWHP, I would also suggest a 383 build. If you were considering going forced induction, you would have to build the motor to handle it anyway. I can not imagine why you dislike the beautiful music that superchargers make. LOL!! Superchargers do make their power in the higher rpm's, but a set of gears would help to reach that power band sooner.
I am actually about to post a Vortech Y-Trim head unit for sale (I just picked up a YSI-Trim). I coincidently have the mounting kit for the 2nd Gen (the kit is new). If you were seriously considering going F/I. Good Luck either way.

TA Dreaming

Thanks. I'll definitely look more into a 383 and see what all is involved in reaching my goal. I appreciate the feedback.

97WS6SCharged

A TC76 turbo on an LT1 with a small cam would make the power you're looking for (and probably a bit more) on low boost. You would need a 44mm or larger wastegate to control it though. Intercooler placement and fitting would be a bit of a trick on a 79 since there isn't a big opening up front like on a Camaro.