Brought to you in part by:

.

Shop Eastwood for your Auto Restoration Needs!


  Mustangsandmore Forums
  Ford Racing
  Backfiring with new cam

Post New Topic  Post A Reply
profile | register | preferences | faq | search

UBBFriend: Email This Page to Someone! next newest topic | next oldest topic
Author Topic:   Backfiring with new cam
Clevo377
Gearhead

Posts: 312
From: Blackburn, Victoria, Australia
Registered: Nov 2000

posted 01-12-2003 01:32 AM     Click Here to See the Profile for Clevo377   Click Here to Email Clevo377     Edit/Delete Message   Reply w/Quote
Just installed a new cam and I'm getting backfire through the exhaust. The cam has a tighter LSA (105) than the old one. Nothing else has changed. Installed it straight up. What would be causing the backfire? The extra overlap, or do I need to re-adjust the carb??

Thanks for any help.

Paul

IP: Logged

MAV
Gearhead

Posts: 144
From: Macon,Georgia, U.S.A.
Registered: Mar 2002

posted 01-12-2003 01:39 AM     Click Here to See the Profile for MAV   Click Here to Email MAV     Edit/Delete Message   Reply w/Quote
WHat kind of engine is it? ... My first wild guess would be that the new cam has a different firing order.

IP: Logged

Clevo377
Gearhead

Posts: 312
From: Blackburn, Victoria, Australia
Registered: Nov 2000

posted 01-12-2003 01:50 AM     Click Here to See the Profile for Clevo377   Click Here to Email Clevo377     Edit/Delete Message   Reply w/Quote
It's a Cleveland. Runs ok, just the occasional exhaust backfire.

Paul

IP: Logged

two89w
Gearhead

Posts: 196
From: sydney australia
Registered: Sep 2002

posted 01-12-2003 04:20 AM     Click Here to See the Profile for two89w   Click Here to Email two89w     Edit/Delete Message   Reply w/Quote
i thought exhaust backfire was to do with lean carburation

IP: Logged

Clevo377
Gearhead

Posts: 312
From: Blackburn, Victoria, Australia
Registered: Nov 2000

posted 01-12-2003 04:53 AM     Click Here to See the Profile for Clevo377   Click Here to Email Clevo377     Edit/Delete Message   Reply w/Quote
I hope that's all it is.. a carb adjustment.

IP: Logged

two89w
Gearhead

Posts: 196
From: sydney australia
Registered: Sep 2002

posted 01-12-2003 05:22 AM     Click Here to See the Profile for two89w   Click Here to Email two89w     Edit/Delete Message   Reply w/Quote
why did you change the cam?

IP: Logged

Clevo377
Gearhead

Posts: 312
From: Blackburn, Victoria, Australia
Registered: Nov 2000

posted 01-12-2003 07:28 AM     Click Here to See the Profile for Clevo377   Click Here to Email Clevo377     Edit/Delete Message   Reply w/Quote
Wanted to see what effect a tighter LSA would have. The project was complete and so I was experimenting a little.

Paul

IP: Logged

Moneymaker
Administrator

Posts: 19704
From: Lyons, IL, USA
Registered: May 99

posted 01-12-2003 11:29 AM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
Exhaust would be rich not lean.
Carb backfire would be due to a lean condition.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00,'01,'02,&'03
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"
www.moneymakerracing.com

IP: Logged

itlbrnmoff
Gearhead

Posts: 746
From: Indianapolis,IN.USA
Registered: Nov 2002

posted 01-12-2003 01:30 PM     Click Here to See the Profile for itlbrnmoff   Click Here to Email itlbrnmoff     Edit/Delete Message   Reply w/Quote
Too much overlap? Raw fuel being sucked into exhaust valve on intake stroke? Flames shooting out of exhaust? COOOOL

------------------
Mustang Lover...
Blue Oval Bleeder...
I've got the scars to prove it...
Society's whipping post...
Low Dollar 1983 Mustang GT W/T-tops...
306 4bbl. T-5 3.45 trac-loc...it'll burn 'em off
1988 Lincoln LSC
5.0 auto full power

IP: Logged

Clevo377
Gearhead

Posts: 312
From: Blackburn, Victoria, Australia
Registered: Nov 2000

posted 01-12-2003 04:32 PM     Click Here to See the Profile for Clevo377   Click Here to Email Clevo377     Edit/Delete Message   Reply w/Quote
So Alex is this normal? Or should I be looking for something wrong? It's happening at idle. All I've done is check the timing and run the cam in. I'm yet to adjust idle mixture.

Paul

[This message has been edited by Clevo377 (edited 01-12-2003).]

IP: Logged

SteveLaRiviere
Administrator

Posts: 33371
From: Saco, Maine
Registered: May 99

posted 01-12-2003 05:24 PM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
Is your exhaust lash set too tight?

------------------
'70 Mustang Mach 1 - '72 Mustang Sprint - '94 F-150

Please remember our sponsors,
Mustangs Plus, NPD, Osborn Reproductions, MyFordPerformance.com, and FordRamAir.com

IP: Logged

Clevo377
Gearhead

Posts: 312
From: Blackburn, Victoria, Australia
Registered: Nov 2000

posted 01-13-2003 03:23 AM     Click Here to See the Profile for Clevo377   Click Here to Email Clevo377     Edit/Delete Message   Reply w/Quote
Don't know Steve, I need to re-check the lash hot now the cams run in. Shall confirm then.

Paul

IP: Logged

All times are ET (US)

next newest topic | next oldest topic

Administrative Options: Close Topic | Archive/Move | Delete Topic
Post New Topic  Post A Reply
Hop to:

Contact Us | Mustangsandmore Front Page

Copyright 2003, Steve LaRiviere. All Rights Reserved.


Ultimate Bulletin Board 5.47d

Amazon Honor System Click Here to Pay Learn More

[Build a free Mustangsandmore.ws Home Page!]

[About M&M][Acronyms][Calendar][Chat][Classifieds] [Members' Pics] [M&M Mug Shots]

[ Mustangsandmore.com Bookstore] [Mustangsandmore.com T-Shirts][Tech Articles]