LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

For those running higher DCR

Thread Tools
 
Search this Thread
 
Old May 19, 2006 | 08:54 PM
  #1  
1LESSZ28's Avatar
Thread Starter
Registered User
 
Joined: Mar 2006
Posts: 344
For those running higher DCR

1. What DCR are you running?

2. What quench are you running?

3. What does your engine setup consist of?

4. Did you have to pull timing?

5. For those running 9:1 or higher what octane gas do you use?

6. Is a 9.1:1 DCR recommended for stock internals (will my motor rattle apart even if I am getting no detonation?) I want to go 45 quench on 93 octane with around a 9.1:1 DCR and 11.5 static. I'm holding my breath and hoping it can be done but I have my doubts. Opinions appreciated. Temperature's are usually in the 90's in SC. Anyone running a similar setup? I do plan on polishing the combustion chambers and water wetter/2" cowl hood/fans and a 160* tstsat.
Old May 20, 2006 | 08:32 AM
  #2  
chrism400's Avatar
Registered User
 
Joined: Jun 2003
Posts: 890
From: Dayton, OH
Re: For those running higher DCR

It'll be close!
Old May 20, 2006 | 06:14 PM
  #3  
1LESSZ28's Avatar
Thread Starter
Registered User
 
Joined: Mar 2006
Posts: 344
Re: For those running higher DCR

Anybody running over 8.7 DCR let me know how its working for you. Especially is you live where it gets hot.
Old May 21, 2006 | 01:50 AM
  #4  
jimbob65's Avatar
Registered User
 
Joined: Nov 1998
Posts: 115
From: WA
Re: For those running higher DCR

I run 8.77 on my combo....

It makes max horse power at 34 degrees up top.....Max torque at around 30 degrees...

We don't get more than 80 degrees here (usually) but, I expect no problems. I have added more timing on the dyno and still did not see any knock retard....I believe I have a little room before any detonation is picked up by the knock sensors (I run stock sensitivity on LT1 Edit, with just a LT4 knock module)....

You need to watch how much actual air flow into the engine (VE) as the more flow, the more closer you come to detonation with a given DCR (generally).....Other things like cooling, outside temp (IAT's), tune, FUEL octane, weight and gear ect...All, have a hand in octane tolerance....

Maybe some other guys will jump in here that can explain it better.....

So, Yeah when running 9 to 1 DCR it will be close, but alot here have done it...I just wanted something I can run the air on hot days and not worry....

Edit...forgot..... .040 quench on this combo...

Last edited by jimbob65; May 21, 2006 at 02:02 AM.
Old May 21, 2006 | 03:23 AM
  #5  
1racerdude's Avatar
Banned
 
Joined: May 2003
Posts: 6,661
From: LA (lower Alabama)
Re: For those running higher DCR

Have run 9.13 with .035 quench on 93 octane with a GOOD tune and no problem.Static is 13.3 on a 383CID.
Ya got to have GOOD cooling(larger rad and Evans coolant)

Ya going to have to tighten the quench or get a larger cam.
It will be fine if ya can stop it from rattleing.

Last edited by 1racerdude; May 21, 2006 at 03:26 AM.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
rideordie
LS1 Based Engine Tech
9
Nov 5, 2019 04:52 PM
DirtyDaveW
Forced Induction
13
Dec 1, 2016 05:37 PM
linz
3rd Gen / L98 Engine Tech
1
Oct 22, 2015 07:59 AM
Javier97Z28
Drag Racing Technique
3
Jul 24, 2002 08:13 AM
guionM
Automotive News / Industry / Future Vehicle Discussion
14
Jun 19, 2002 08:30 AM




All times are GMT -5. The time now is 05:42 AM.