yj wranger with 350 having problems - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > General Technical Discussions > Advanced Jeep Tech > yj wranger with 350 having problems

Attention to the TJ owners 1996-2006 NEW LED LIGHT OPTIONSOPTIC ARMOR WINDOWS all sale now !!!!!!!!FS: 2007-2013 Jeep Wrangler "HALO" Angel Eye Kit

Reply
Unread 08-12-2013, 06:39 PM   #1
motormike24
Registered User
 
Join Date: Feb 2013
Location: Rockford, MI
Posts: 77
yj wranger with 350 having problems

hey guys its been awhile but im back. had to put the jeep project on hold for a while but im back at it. just a brief recap - 90 wrangler with a freshly rebuilt 350 bored .40 over and otherwise factory build. was a carbed 350 originally but since already had the tbi wiring set up from the inline 6 that had been in it, we opted to run it tbi. im running the 7747 computer and swapped the injectors from 4.3 injectors to the 350 injectors. fuel pressure is perfect. 14-15 psi. new plugs and wires, aftermarket jeep over-the-frame headers with cherry bombs. great injector pulse, tfi coil (although I believe its too hot of spark due to melting the rotor pin in dist cap twice.) could not get it to base timing of even close to 0 degrees. after lots of hours of messing with distributor and removing timing cover to verify timing marks on the cam and crank gears are dead on, found the harmonic balancer had "walked" and just replaced that tonight. now, we brought cyl 1 to TDC compression stroke, set distributor, and fired it up. fired instantly but ran like ****. got it finally to base timing of 0 degrees, but still wouldn't stay running. revving it up at all shot 3 foot flames out the tbi. its acting like the timing is extremely off, however ive verified cam timing and even tried flipping the dizzy 180, but then it failed to fire at all. I KNOW the dist is set right. however its acting so crazy im bout to pull my hair out.the cam is "supposedly" factory specs for the gen 1 350. nothing modified in the valvetrain. great compression. what the heck could it possibly be?the only way it will rev at all is if its advanced to 10 to 15 degrees btdc. and no matter what I do I can see intermittent flames below the throttle plates. im very much lost for any more ideas. any help with this will be appreciated.

motormike24 is offline   Reply With Quote
Unread 08-12-2013, 08:11 PM   #2
motormike24
Registered User
 
Join Date: Feb 2013
Location: Rockford, MI
Posts: 77
Quote:
Originally Posted by motormike24 View Post
hey guys its been awhile but im back. had to put the jeep project on hold for a while but im back at it. just a brief recap - 90 wrangler with a freshly rebuilt 350 bored .40 over and otherwise factory build. was a carbed 350 originally but since already had the tbi wiring set up from the inline 6 that had been in it, we opted to run it tbi. im running the 7747 computer and swapped the injectors from 4.3 injectors to the 350 injectors. fuel pressure is perfect. 14-15 psi. new plugs and wires, aftermarket jeep over-the-frame headers with cherry bombs. great injector pulse, tfi coil (although I believe its too hot of spark due to melting the rotor pin in dist cap twice.) could not get it to base timing of even close to 0 degrees. after lots of hours of messing with distributor and removing timing cover to verify timing marks on the cam and crank gears are dead on, found the harmonic balancer had "walked" and just replaced that tonight. now, we brought cyl 1 to TDC compression stroke, set distributor, and fired it up. fired instantly but ran like ****. got it finally to base timing of 0 degrees, but still wouldn't stay running. revving it up at all shot 3 foot flames out the tbi. its acting like the timing is extremely off, however ive verified cam timing and even tried flipping the dizzy 180, but then it failed to fire at all. I KNOW the dist is set right. however its acting so crazy im bout to pull my hair out.the cam is "supposedly" factory specs for the gen 1 350. nothing modified in the valvetrain. great compression. what the heck could it possibly be?the only way it will rev at all is if its advanced to 10 to 15 degrees btdc. and no matter what I do I can see intermittent flames below the throttle plates. im very much lost for any more ideas. any help with this will be appreciated.
I should add that I have since pulled all the wires off the cap and started over using the normal factory firing order with cyl one plugwire starting on the forwardmost post on drivers side (when viewing cap as the front two posts are side by side). also got it timed base timing at 0 and it stays running now, with very minimal backfiring through intake. I have instant throttle response now however if I hold the throttle in one position for more than a split second it will begin to bog down badly and any increase in throttle it will revv up great. but..... it does NOT like being held in one set spot. also does not help to hook up EST connector. runs the same, but with timing light I can see it has advanced it well before any of the notches on the timing cover. also runs so rich I can only run it a minute or two at a time before my eyes burn so badly I cant see. what could this issue be???
motormike24 is offline   Reply With Quote
Unread 08-17-2013, 08:11 PM   #3
fang_x
Registered User
1998 TJ Wrangler 
 
Join Date: Jun 2009
Location: Montreal, Canada
Posts: 1,252
You might have better luck on the http://www.hotrodders.com/forum/ website

Ive got an old car with a 350, their engine guys are very knowledgeable about that motor and helped me out with mine.
__________________
'98 TJ Manual -2.5" rcx long arm on 31
'99 Xj, Stock on 30"
'86 Monte Carlo 357 stroker. 450hp.
fang_x is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.