LT5 engine upgrade question

[cvette98pacecar]

Originally Posted by Fully Vetted

Are those BB cars, Robert? What's the strongest 368 that you've heard of?

Those are all 396 or larger, Mark H car if I remember correctly has a 385 that has 625hp without the power adder.
Todd is still trying to get 800hp out of a 427. Thinking he should install "Oh **** Handles on the Targa top".

For the 368 cu in. 530-550hp. I can honestly tell you that my LPE 368 would leave my DRM500 in the dust. However, I do not believe any of the LPE 368 have a fully ported top end, back in the day all porting was done to 34MM. Maybe Locobob has a fully ported 38mm top end with cams and fully ported and shaved heads.

Now Dom's car has to have the same numbers 530-550hp with a 350 bottom end.
Then there is the mysterious 350 that has to be putting out between 575 and 600hp. That car is just sick.

IMO if you are going to do a stroker, you either do a 396 like Dennis or a 402 like Phil. They both have the same horsepower as the 415 or larger cubic inch engines without all of the side loading.

[1995BLACKZR1]

Thanks so much for the information. How long does Marc usually need the car? Is he based in Chicago? The 510 package sounds great. Yeah I have read a lot on the LT5 motor and it's very impressive. One thing I like about this car is you don't see many C4's on the road anymore and it being a ZR1 makes it even more rare. I also want to switch the rims out for a deep set chrome type which I think will look amazing.

[cvette98pacecar]

Originally Posted by 1995BLACKZR1

Thanks so much for the information. How long does Marc usually need the car? Is he based in Chicago? The 510 package sounds great. Yeah I have read a lot on the LT5 motor and it's very impressive. One thing I like about this car is you don't see many C4's on the road anymore and it being a ZR1 makes it even more rare. I also want to switch the rims out for a deep set chrome type which I think will look amazing.

Pd Buck has a set of chrome, he is looking for stock wheels. Here is the link.

http://www.zr1.net/forum/showthread.php?t=25330

[XfireZ51]

It never gets boring driving a DOHC motor w 500+ hp under foot. The power delivery is smooth, effortless, and seemingly just goes on and on.

[Demps]

The top end ported 350s are an extremely enjoyable drive. They maintain stock drivability demeanor and pack a punch. If you have the coin to immediately go that route, I'd recommend.

Consider this though: if you can escape with headers in your area, put them on now. You'll want them with the porting. I've found stock '95s in the 345 rwhp range. Exhaust adds to ~360 rwhp (+~7 w/ x-pipe). Headers and chip with all above will get you to ~390 rwhp. All cars respond slightly different which I think is cam timing.

Marc's packages and his care are second to none. It does take time though. He can tell you and is usually in the ballpark.

BEWARE: whatever you do it will be just short of enough.

Evidence:
Stock
Stock with headers exhaust
Ported 350
Ported 350 with cams
415 with cams

Ted

[XfireZ51]

I have gone through a similar "evolution" as Ted with the exception of remaining in the 5.7L displacement class. Each step brought additional hp with it and the "need" to push on. The ported top end w headers is a really nice package but surprisingly (seriously) I found that ported heads + Pete's intake cams was an even better combo. So much so that I was hesitant to do the exhaust cams concerned w giving up idle quality and part throttle cruise for some additional power. Its taken a bit of time and effort BUT its definitely been worth it. More recently, I have been working on getting the tune right for the notorious free-wheeling decel surge and am pretty pleased with where its at. The accelerator is really smooth and I'm seeing an indicated 30-32mpg at 65mph on a level road. The exhaust cams are worth about 20rwhp from just the intake cams.

[Jagdpanzer]

Be careful, when it come to HP … to much is never enough

[LT5Vette]

I don't believe anyone is unhappy with any of Marc's upgrade packages. As others have warned horsepower like any addiction craves more and more and just a little bit more. I'm happy with what I have really, I am.

[SAM/CH ZR-1]

A 368 with 510 HP pulls noticeable different (stronger) than a 350 with 510 HP. When it's about more cubic inches, go first with a bigger bore and longer rods. Make the crank leighter and the engine get a incredible trottle response.

[5ABI VT]

If he said 70 hp from exhaust... I would double check everything he told you. Are you sure the car is a zr-1 and not an LT1 with a sticker?