2000WS6TA

iTrader: (5)

hey guys, havent been on here for a while, trying to get back at it with the trans am. have a few questions that searching didnt really help. im planning a 383 stroker on a lS6 block with the intentions of adding a turbo later. now my question is could i set the whole motor up, low compression, turbo cam, 317 heads and for now headers and h pipe exhaust WITHOUT the turbo on the car. basically im asking would the motor run funny or not well at all with the low compression and turbo cam. im still weighing out turbo options and want to get the motor in and broken in before the turbo goes on. and i only want to have to do the rotating assembly and cam once so i dont want to get high comp pistons now and low later and swap cams ect. or could leaving stock 241s on help boost compression for now or even 5.3 heads?

thanks guys sorry if any of that is confusing.

Jefro6996

iTrader: (21)

It wouldn't run funny, it would just be down on power and might be a little sluggish depending on the compression you choose. I'm running my 408 turbo motor with a turbo cam N/A right now and it isnt the best performing it could be N/A with the compression, cam and rear gears, but its still fast a car for what it is. My compression is right at 9.95:1 though. Not as low as most turbo guys, but I'm going to be running E85. Running the 5.3l heads would help you to bump compression up a bit and leave the same pistons in the car, but do you want to have to swap heads later down the road for a few hp while you run it N/A. I chose not to and just run the setup as is. I'm happy with the 480rwhp i have with the turbo cam, 4l80e trans and 9" rear. I drove it all last year like this.

Chevy406

iTrader: (12)

I drove my 408 for a little while naturally aspirated - 9:1 compression, reverse split cam and truck exhaust manifolds it ran 7.5s in the 1/8th mile. Was very soft feeling but ran well enough on 87 octane.

But once I added a couple turbos and doubled the inlet pressure it is a very different experience.

Go ahead and break in in naturally aspirated until your budget allows for boost, but don't wait too long.

2000WS6TA

iTrader: (5)

thanks man. if thats the case ill just set it up as if the turbo was on the car. and i think i was going to run my compression at around 8.5 or 9:1 then when im ready ill just slap the turbo on and be ready to roll.

Exidous

iTrader: (11)

I would think 8.5 would be a little low for a street car. I am about to buy a rotating assembly and folks that I've talked to suggest the 9.5-9.8 range. I'm planning 93 Oct and reasonable boost no meth. Purely a street car without crazy aspirations. Yet. E85 I'd go 10-10.5:1

The higher your goals the lower the CR will have to be. Gasket gives you a little wiggle room but not much. All out race cars run in the 8's. The ZR1 gets away with a lower 9:1 because it's PD that covers power lost due to CR and has plenty of safety margin.

2000WS6TA

iTrader: (5)

maybe ill bump compression to around 9.5 then. thanks for the input guys

NicD

iTrader: (7)

8.5:1 compression 347 ci, ran without a turbo for a few months and it still made 400 rwhp on the dyno.

Forcefed86

iTrader: (4)

Depends what you consider running funny? I think you'll be fine. My gen1 SBC 383 boost motor still went 13.6 @ 114 on street tires with 7.9:1 compression on 87 octane. In a 4000lb Gbody.