Runn

I have a question for you

If i lower my CR to 9:1 how sluggish will the car feel compared to a stock LS1 if i start from stop... What are youre experiences with boost and a lower CR. I know this depends on a lot of factors but i´m only looking for some info
Thanks.

I´m going to have a Inconkit on my car with two GT3776R.

02SSLE

iTrader: (26)

my car with forged 347 was really sluggish till I figured out how to take off. I have to rev to 4500 rpm and dump the clutch and then I would imediatley have boost. the CR was 9.1

bad95killer

Not 346ci but my buddy's Y2K C5 M6 equipped with 408ci the CR dropped down to 8.7:1 for 300+shot moves damn well & ya can say better than full bolt-ons LS1 esp. from low roll or dig so i don't think that considered to be sluggish,Btw he has 3.42's & he spinning thru 1st 'n 2nd on street tires damn hard

Anyway keep us updated with progress

peace

Pro Stock John

iTrader: (34)

Figure a 3% decrease in power from 10:1, that's nothing to worry about. It's the bigger cams that make forged engines feel like they lack low end.

gametech

iTrader: (1)

Sounds like someone has good plans for Josh's old Incons.

mdhmi

iTrader: (1)

My CR is in the high 8's and don't have any problems with partial throttle umph. Properly sized torque convertor is priceless.

LSs1Power

iTrader: (5)

My 408 has a 8.4 C/R and it doesnt feel sluggish at all. It dyno'd 430rwhp 450rwtq on a Mustang dyno N/A. It is still running the LS6 manifold with stock TB too.

2002/Black/SS

iTrader: (3)

i saw no difference after i put on my 6.0L heads, no lose but no gain

TurboGoat

I hope this stuff is true, I am setup to have an 8.8 to 9 ratio and I am hearing from some people that it might feel like a dog off boost, hope not.

346 with T76MPS turbo. I am going to run my vig 3200

camarols1

iTrader: (17)

If the car is tuned properly with a matched converter you will be fine.

Runn

Only a 3% drop if i lower to 9:1, dont sound so bad... 350-3% = 335-340.

Pro Stock John

iTrader: (34)

That's the number I have seen a few times, 3%. Even if it's 5% it's still not bad.

thunder550

iTrader: (70)

Big on this. My 408 sucks coming out of the hole. I'm 9.5:1 SCR, about 7.0:1 DCR with the cam I'm running. Built the motor for boost, but running it N/A for now. Best I could pull at the track was a 14.89 @ 97 with a 2.4 60'. I had a stock 6.0 with a Radix at 7 psi before and ran a 13.66 @ 104, 2.05 60'. I was hoping to be close with the N/A 408 but it's just a dog down low.

Pro Stock John

iTrader: (34)

My DCR on boost is huge it's like 17:1, are you na right now with that truck?

thunder550

iTrader: (70)

Yeah for now, hoping to have a turbo on it sometime in the next 6 months or so. Even if I could hit 20 psi I'd still only be 16:1 DCR.

Phil99vette

iTrader: (11)

I think the key to low compression is having a good set of heads on the top end to make up for it. My next combo is going to have 8.0:1 CR but topped with some bad boy ET LS7 heads flowing over 350cfm.
Phil

Runn

Thanks for the answers.

Fire67

iTrader: (3)

We just put together a 8.25:1 355 Ltx motor for my buddy's turbo project. We installed the motor without the turbo to do break-in. On a stock tune, AFR 195's, stock injectors, LT4 intake - extrude honed, and a baby turbo cam, the car pulls waaayyyy harder than the stock full bolt-on Lt1 did.

Im sure its not making as much N/A power as it could if we had left the compression alone, but its still not sluggish by any means. Once the turbo gets here it'll be on!

anarchy99

iTrader: (7)

I ran my car for awhile with the wastegates setup so no boost would come on. (engine break-in) 8:5-1 compression ratio. Not sluggish like you would think. Car drove like it did before I put everything on it. Now that it's in boost it's awhole different story!!!