If my compression is 8.5 will...
Thread Starter
TECH Apprentice
Joined: Aug 2002
Posts: 335
Likes: 0
From: northern cali.
If my compression is 8.5 will... If my compression is 8.5 will it be a dog on a H/C car until I get my blower done or should I do more like a 9.1:1 comp ratio so I can still drive her ok?
i used 8.9:1 CR on my turboTransAM aand its not that bad off boost
it still will pull hard enough to throw you back into the seat but when the turbo it pulls you back into the seat even more.
one thing i noticed was that my gas milage also droped 3mpg by going with the lower compression engine.
it still will pull hard enough to throw you back into the seat but when the turbo it pulls you back into the seat even more.
one thing i noticed was that my gas milage also droped 3mpg by going with the lower compression engine.
10 Second Club
Joined: Apr 2002
Posts: 1,755
Likes: 2
From: Cincinnati, Ohio
I had my 382 at 9:1 comp. and it was too soft for me down low. When I went to the 418 I bumped it up to 9.5:1, of course the cubes helped too but it has way snappier throttle response and low end torque. The max timing I could put in was 16 degrees (with 94 octane) until I put on the Alky injection which has extended that. I'm at 18 now with no KR and will soon try 20 and maybe I can go beyond that. SMC says you can put in up to 25% more timing. So I think 8.5 is too low unless its a strip only car with high boost and race gas. If your choice is between 8.5 and 9.0 on a street/strip car I would definitely vote for 9.0.
Thread Starter
TECH Apprentice
Joined: Aug 2002
Posts: 335
Likes: 0
From: northern cali.
Originally Posted by Pro Stock John
I would the lowest compression possible in the end you will be less dependent on higher octane as you push your combo.
In my 348ci...
2001 LS6 block, bored 3.905
Diamond -8.6cc FI pistons
Eagle 6.125 rods
6 liter heads, 2.02/1.57 valves, 300/220 flow numbers
GM MLS 6.0 head gaskets
FMS/Cam Motion 230/236 cam
Comp R Lifters
Y/T 1.7 rockers
Crane valve springs
Ported Oil pump
Bauer ported TB
LS6 Intake
ARP main studs
L19 head studs
L19 rod bolts
Stock crank
Basically I built this motor to see if I could build a budget-minded stock cube engine.
2001 LS6 block, bored 3.905
Diamond -8.6cc FI pistons
Eagle 6.125 rods
6 liter heads, 2.02/1.57 valves, 300/220 flow numbers
GM MLS 6.0 head gaskets
FMS/Cam Motion 230/236 cam
Comp R Lifters
Y/T 1.7 rockers
Crane valve springs
Ported Oil pump
Bauer ported TB
LS6 Intake
ARP main studs
L19 head studs
L19 rod bolts
Stock crank
Basically I built this motor to see if I could build a budget-minded stock cube engine.
Trending Topics
TECH Enthusiast
Joined: Nov 2003
Posts: 689
Likes: 0
My motor is a 377, 7.5:1 compression, in a heavy SN95 mustang. I drove it around for a while naturally aspirated, and the car ran fine. Throttle response was fine, had enough low end, and you can run a lot more boost and make a ton more power on lower compression and more boost than you could ever hope to make with higher compression and less boost, on pump gas of course.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
TECH Senior Member
Joined: Nov 2001
Posts: 11,603
Likes: 0
From: Chi-Town, IL
Maybe if I ever decide to go back into my motor and put a stroker crank in, I might change the pistons while I'm in there......
There is nothing like a lot of boost w/pump gas.........
There is nothing like a lot of boost w/pump gas.........
Thread Starter
TECH Apprentice
Joined: Aug 2002
Posts: 335
Likes: 0
From: northern cali.
Originally Posted by Pro Stock John
Yes I run a stock crank.
