Go Back   Third Generation F-Body Message Boards > Tech Boards > Alternative Port EFI Intakes
Sign in using an external account
Register Forgot Password?

Alternative Port EFI Intakes This board is for tech discussions and questions about aftermarket port EFI such as the HSR, MR, SR, BBK, FIRST, etc.

Welcome to ThirdGen.org!
Welcome to ThirdGen.org.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join the ThirdGen.org community today!


Reply
 
Thread Tools Search this Thread
Old 03-22-2009, 07:40 PM   #1
Member
 
Join Date: Oct 2005
Location: Kentucky
Posts: 130
Car: 84 Monte Carlo SS
Engine: 408
Transmission: 700-r4

Classifieds Rating: (0)
Retarded cam 4*, now won't fire

When the weather got too cold to drive the SS I decided to install some new valve covers and since I was pulling the valve covers I might as well pull the intake because I had a little coolant leak at the front passenger side. Of course since I was doing all that I thought I would retard the camshaft to help bleed off some of the mid range cylinder pressure. It seems that with a 10.3:1 compression 408 and the fast ramps of the Voodoo cam (262/268, 219/227@.050) my engine did not like much timing at all (in the 60-90 kpa range) even though I was running 93 octane. I wanted to change camshafts but thought the cheaper thing to do is retard the cam and see if the situation improves. So I installed the bottom crank gear with the rectangle (for 4* retard) at the 12 o'clock position and the timing gear had the dot at 6 o'clock. The #1 cylinder was at TDC verified by the position of the piston and the #1 exhaust and intake valves were closed. After things were buttoned up I dropped in the dist. and rotated the engine slightly so that the timing mark was at 8* BTDC and the rotor was pointing at the #1 terminal. Now when I went to fire the engine it kicked over but did not fire. For some reason it sounded like the spark was happening too late. What it sounded like was the spark was happening when the exhaust valve was open as the exhaust was popping. So I stopped and reverified that the engine was at TDC and the rotor was pointing at the #1 terminal. I tried again and got the same results. I even rotated the dist. to advance it and the situation did not improve. I just ended up soaking the plugs with fuel. So now I am thinking that I potentially have the timing gear a tooth off if. Even though I swear the marks were at 6 and 12 o'clock. Unless someone sees a flaw in how I timed the engine. Any suggestions? I want to get the SS running now that the weather is turning nice.
__________________
10.5:1 408 SBC, AFR195, 219/227@.050, HSR w/52mm TB, 30lb inj, 730 ECM, long tube headers, dual exhaust, LT1 Fans
84KYSS is offline vBGarage Page   Reply With Quote
Old 03-23-2009, 01:19 AM   #2
Junior Member
 
Join Date: Sep 2008
Location: Jackson, MI
Posts: 95
Car: 1991 Pontiac Firebird
Engine: 3.1L V6
Transmission: 700R4
Axle/Gears: 3.23

Classifieds Rating: (0)
Re: Retarded cam 4*, now won't fire

So I take it your getting some detonation at that range? What are your plugs gapped at? Have you tried a colder spark plug?
Once you have an engine with really high compression and/or big cams, then fine tuning heat ranges and gaps become more critical.
__________________
-Greg-
Finally got a thirdgen (06/21/09).
tazextreme3 is offline vBGarage Page   Reply With Quote
Old 03-23-2009, 06:40 PM   #3
Member
 
Join Date: Oct 2005
Location: Kentucky
Posts: 130
Car: 84 Monte Carlo SS
Engine: 408
Transmission: 700-r4

Classifieds Rating: (0)
Re: Retarded cam 4*, now won't fire

I haven't tried a colder plug. I was using the standard plug suggested by AFR which crosses to an Autolite 3923. I did just install a set of 3922s. The issue I think I have is my dynamic compression is too high. With a static of 10.3:1 my dynamic compression ratio was 8.67:1 with the Voodoo cam installed at the recommended centerline (the cam is ground with 4* advance and the installed centerline is 108). I've read that anything over 8.3:1 or so is too high and anything over 8.6:1 is for race cars (leanred this after the engine was built). So I thought that I would retard the cam 4* which brought the dynamic comp. to 8.3:1. I thought that with the 3922 plugs would take care of the situation. Just can't get the engine to fire now. I use .035 gap as I've read the closer gap is better for higher compression. I'm about to pull the timing cover to confirm that I got things lined up.
84KYSS is offline vBGarage Page   Reply With Quote
Old 03-24-2009, 08:41 AM   #4
Member
 
Join Date: Jun 2004
Location: PA
Posts: 184
Car: 94 9c1 Caprice
Engine: LT1 (3-fity)
Transmission: 4L60E reBUILT
Axle/Gears: 3:08 POSI (out)

Classifieds Rating: (2)
Send a message via Yahoo to zipfast
Re: Retarded cam 4*, now won't fire

Hold on there...
Dot to dot is #6 fire position.
Both dots up (12 o'clock) is #1 fire position.

That said your 180 out.
Pick the dissy up till you can spin the rotor and
spin it 180, drop it back in...GOOD TO GO..
zipfast is offline vBGarage Page   Reply With Quote
Old 03-24-2009, 11:42 AM   #5
Member
 
Join Date: Oct 2005
Location: Kentucky
Posts: 130
Car: 84 Monte Carlo SS
Engine: 408
Transmission: 700-r4

Classifieds Rating: (0)
Re: Retarded cam 4*, now won't fire

Thanks Zipfast. I did not know that. That's an easy fix.
84KYSS is offline vBGarage Page   Reply With Quote
Old 03-24-2009, 03:25 PM   #6
Member
 
draco's Avatar
 
Join Date: May 2006
Location: Parkersburg WV
Posts: 286
Car: 1991 Camaro RS
Engine: 3.1l V6
Transmission: 700R4 Automatic
Axle/Gears: Stock 3:23

Classifieds Rating: (0)
Send a message via AIM to draco
Re: Retarded cam 4*, now won't fire

I agree, looks like you might have set it for TDC on the exhaust stroke or you have the dizzy 180 out.
__________________
-1991 Camaro RS 3.1l V6
-1987 Camaro Sport Coupe Project
draco is offline vBGarage Page   Reply With Quote
Old 03-24-2009, 03:25 PM
ThirdGen
1992 Camaro




Paid Advertisement


Reply

Go Back   Third Generation F-Body Message Boards > Tech Boards > Alternative Port EFI Intakes

Tags
4, 93, alternatives, cam, cam4, cam4now, camaro, fire, gen, installed, retarded, tube, voodoo, wont, working
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 


1982 Camaro '82 || 1983 Camaro '83 || 1984 Camaro '84 || 1985 Camaro '85 || 1986 Camaro '86 || 1987 Camaro '87 || 1988 Camaro '88 || 1989 Camaro '89 || 1990 Camaro '90 || 1991 Camaro '91 || 1992 Camaro '92


All times are GMT -5. The time now is 02:47 AM.


Powered by vBulletin® Version 3.7.5
Copyright ©2000 - 2012, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.5.2
All content copyright © 1997 - 2012 ThirdGen.org. All rights reserved. No part of this website may be reproduced without the expressed, documented, and written consent of ThirdGen.org's Administrators.

Emails & Contact Details