Forced Induction Superchargers | Turbochargers | Intercoolers

boosted 370...what compression?

Thread Tools
 
Search this Thread
 
Old Mar 3, 2009 | 07:47 PM
  #1  
LM7 Sportside Z71's Avatar
Thread Starter
Staging Lane
iTrader: (2)
 
Joined: Mar 2005
Posts: 54
Likes: 0
From: Southern Wisconsin
Default boosted 370...what compression?

im boosting a 370, thinking either 72 cc 6.0 heads or going the L92 70cc route. my goal is 800rwhp on 93 octane. thinkin prob an aps twin turbo kit unless anyone else has a better suggestions??? this is also a M6 street car so i want least amount of lag as possible. what im wondering is what compression ratio should i shoot for to make my car not be a dog when in vacuum but still be able to get my 800whp on 93 octane? any help would be greatly appreciated!
Reply
Old Mar 3, 2009 | 08:42 PM
  #2  
nastychevelle's Avatar
TECH Resident
iTrader: (7)
 
Joined: Jul 2008
Posts: 934
Likes: 1
From: troy, IL
Default

L92 easy they flow way better than the 6L heads so you'll probably need less boost to make the same power so the extra 2cc wont be needed and it will raise your compression some (not alot) and give you more torque
Reply
Old Mar 3, 2009 | 08:56 PM
  #3  
trans2000am's Avatar
TECH Fanatic
iTrader: (49)
 
Joined: Feb 2006
Posts: 1,518
Likes: 0
From: detroit
Default

m6 is gonna be worse on lag and to keep boost up. id go 4l80e or th400
Reply
Old Mar 3, 2009 | 08:58 PM
  #4  
LM7 Sportside Z71's Avatar
Thread Starter
Staging Lane
iTrader: (2)
 
Joined: Mar 2005
Posts: 54
Likes: 0
From: Southern Wisconsin
Default

yea i think im pretty set with my 6 speed though...dont really want an automatic however i do def understand what your sayin with the lag issue....
Reply
Old Mar 3, 2009 | 09:00 PM
  #5  
LM7 Sportside Z71's Avatar
Thread Starter
Staging Lane
iTrader: (2)
 
Joined: Mar 2005
Posts: 54
Likes: 0
From: Southern Wisconsin
Default

i mainly am looking for what compression ratio i should shoot for with this setup? im thinkin 9-1 all the way upto 9.5-1 or anywhere inbetween???
Reply
Old Mar 3, 2009 | 10:05 PM
  #6  
The Beast's Avatar
TECH Apprentice
iTrader: (16)
 
Joined: Feb 2008
Posts: 363
Likes: 0
From: Fort Wayne, IN
Default

I went with 9:1
Reply
Old Mar 3, 2009 | 10:07 PM
  #7  
MY99TAWS6's Avatar
TECH Veteran
iTrader: (3)
 
Joined: Apr 2002
Posts: 4,719
Likes: 3
From: Kelowna,BC
Default

I have 9.5 to 1 with wiseco custom pistons and afr 225 72cc heads. Thicker heads trick flow or afr for example are good idea if you want to push things to higher power.
I plan on alc injection and have access to 94 octane in my city. Although sometimes 92 is best can find. The alc injection shoudl give me the extra securty on pump gas.

M6 has some advantages. You can gear down when in say third or fifth or sixth to spool up the turbos pretty much instantly. You can get a two step from lingenfelter with antilag both of which can also help an m6 car spool up fast off the line.

I am going to 4l80e and already ordered new yank stall. I am sick of m6 ,clutch rattle, shifter rattle, sick of hydraulics and clutches. So far my tex twin seems to be working fine but whatever.

I see no reason to go under 9.5 unless you don't want to run an alc injection system.
Then you might want to go 9.0. Can see real reason for under 9.0 unless your trying to run 87 or something?
Reply
Old Mar 3, 2009 | 11:24 PM
  #8  
LM7 Sportside Z71's Avatar
Thread Starter
Staging Lane
iTrader: (2)
 
Joined: Mar 2005
Posts: 54
Likes: 0
From: Southern Wisconsin
Default

yea i really dont want to have to run an alc injection system i guess...more money and wouldnt need the extra hp probably. I would rather just run my FMIC and try and make 800+ at the wheels. so im thinkin mayber lower to mid 9s for compression ratio from what im hearing...
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Mar 3, 2009 | 11:27 PM
  #9  
theblur98ss's Avatar
TECH Junkie
iTrader: (71)
 
Joined: Mar 2002
Posts: 3,703
Likes: 0
From: East Brady, Pa
Default

9 to 1 is a good number. I'm at 9.3 to 1 on mine. A little higher then I wanted but I got a good deal on a set of heads. In the end I think it may work out for the better.
Reply
Old Mar 5, 2009 | 12:51 AM
  #10  
XpEdItIoUs's Avatar
10 Second Club
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (44)
 
Joined: May 2004
Posts: 1,658
Likes: 0
From: Phoenix, AZ
Default

anyone at 9.5:1?
Reply
Old Mar 5, 2009 | 05:06 AM
  #11  
SPLATT's Avatar
TECH Enthusiast
20 Year Member
iTrader: (1)
 
Joined: Jan 2006
Posts: 634
Likes: 8
From: San Diego, CA
Default

so on a stock LQ9 what is the easiest way for 9:1? also, cost effective? im planning a turbo build as well but on a budget. and not looking for over 600RWHP just yet lol.
Reply
Old Mar 5, 2009 | 11:47 AM
  #12  
The Beast's Avatar
TECH Apprentice
iTrader: (16)
 
Joined: Feb 2008
Posts: 363
Likes: 0
From: Fort Wayne, IN
Default

317 heads and cometic head gaskets
Reply
Old Mar 5, 2009 | 01:53 PM
  #13  
tomz28's Avatar
9 Second Club
iTrader: (20)
 
Joined: Sep 2007
Posts: 1,813
Likes: 0
From: Saline, MI
Default

Originally Posted by trans2000am
m6 is gonna be worse on lag and to keep boost up. id go 4l80e or th400
he is 100% right

9to1 would be best for the street
Reply
Old Mar 5, 2009 | 02:08 PM
  #14  
MY99TAWS6's Avatar
TECH Veteran
iTrader: (3)
 
Joined: Apr 2002
Posts: 4,719
Likes: 3
From: Kelowna,BC
Default

You can get boost off the line with a two step like lingenfelter sells and it also has antilag option for even more boost off the line. Standards can also put you into boost quick if you are in a higher gear like third in city or fifth or sixth on highway. Just band down a gear or two and you will have boost fast.
Standards can loose boost between shifts if you don't use basically no lift to shift power shifting to keep things spooled up.

I am going to 4l80e in my car mostly for other reasons. I am sick of twin disc floater rattle, I am sick fo m6 shifter rattle and extra noise. I am sick of hydraulics and clutches in general and shifting in traffic.
Reply
Old Mar 5, 2009 | 06:00 PM
  #15  
TurboAv's Avatar
TECH Fanatic
iTrader: (6)
 
Joined: Oct 2005
Posts: 1,455
Likes: 1
From: Tonopah, AZ
Default

What about 8.5:1 for a pump gas car with a TH400, 4000stall, and no meth. Racegas for the track.
Reply




All times are GMT -5. The time now is 08:12 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE