Backfiring...help
Thread Starter
Pro
Joined: Jan 2001
Posts: 602
Likes: 0
From: Aliso Viejo CA
Backfiring...help
Ok, see sig for most details, but I put a new 383 in and it was running rough. The only things that werent new were a used set of 30# injectors and the distributor. I had the injectors cleaned and flowtested, they are within 2%. (cant recommend Rich at http://www.cruzinperformance.com enough). I got a rebuilt distributer, new cap, new rotor. Put it all in. Disconnected the tan and black wire near the firewall on the driver's side and set the timing to 6*. It is way smoother than before. Problem is this: When I plug the wire back in and start the car I get succesive backfires one after another...big ones. What the hell? Ideas?
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Re: Backfiring...help (Warlock)
The last time I experienced this, the distributor wasn't in correctly and believe me, it can be a nightmare if you're off a tooth. Get the timing mark lined up to TDC and see where the rotor is pointing. Should be allmost midway between the number 1 and number 8 tower. If not, then it's probably not in correctly.
Safety Car
Joined: Dec 2000
Posts: 3,767
Likes: 5
From: Jacksonville Fl
Re: Backfiring...help (SunCr)
What comes to mind is the timing mark not lined up correctly? I take it you have a new externally balanced damper ( 383 right...) ?
I do know some dampers will have the TDC mark in a different place than others, which is why GM made two timing pointers ( I think the 8" balancer has the mark about 20 degrees or so off from the 7" version...because it used a different pointer due to differences in the size of balancers ).
I would get a piston stop tool and do a TDC check to make sure the balancer is accurate...or reduce your timing by about 20 degrees, reconnect the dist wire EST connectors and drive it, bump the timing up a few degrees at a time until it pings a little under heavy load then bump it down a few degrees from there. ( Thats the redneck way of setting timing :D )
[Modified by BBA, 11:45 PM 10/1/2001]
I do know some dampers will have the TDC mark in a different place than others, which is why GM made two timing pointers ( I think the 8" balancer has the mark about 20 degrees or so off from the 7" version...because it used a different pointer due to differences in the size of balancers ).
I would get a piston stop tool and do a TDC check to make sure the balancer is accurate...or reduce your timing by about 20 degrees, reconnect the dist wire EST connectors and drive it, bump the timing up a few degrees at a time until it pings a little under heavy load then bump it down a few degrees from there. ( Thats the redneck way of setting timing :D )
[Modified by BBA, 11:45 PM 10/1/2001]
