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Discussion Starter #1
can anyone help me?

i own a 1989 chevy camaro rs
it used to have a 305 tbi but i blew a piston ring so i decided to replace it with a 350 i had in a parts camaro....

the 350 was not running at the time but after i bolted the 350 up to my transmission i dropped it in and used my tbi fuel injection system and distributor and it fired right up....

now the problem is as it sits and idles it runs amazing doesnt miss a beat but as soon as i drop it in R or any forward gears its idle drops dramatically and hardly runs as i try to excelerate it bucks and pops back through the throttle body then it dies... i can start it up and itll idle perfectly fine again but once i start drive it does it again..... another thing is the overdrive no longer works it used to...

what could be some possible causes im at a loss
im a h.s student and no longer have any way to school
can some one help me??? please :confused:
 

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Discussion Starter #2
acceleration

i have a 89 camaro that origanlly had a 305 tbi now has a 350 tbi
the car idles fine when in park and when sitting still but once you try to drive the car whether it be in any forward gear or reverse it bucks and backfires through the carb then dies...overdrive no longer works either...everything bolted up and all the wiring and sensors all worked before the engine swap :confused:

the car ran great before...
could it possibly be timing idk whether the 350 was professionaly built or not it was in a parts car i had sitting around the previous owners said it ran so idk....i pulled it and dropped it in my car and it started up like nothing...

i need help....
could it be timing, or possibly my torque converter lockup switch, or my iac (idle air control? valve?
 

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Both TBI,
if it is the same TBI, did you recalibrate computer for the larger engine? It could be LEAN misfire under even slight load.

I think you have multiple unrelated problems.

I would check every connection, clean, tighten prongs for solid grip, and put silicone dielectric grease in every connector.

I've told lots of people out in the field..... multiple symptoms.... check connectors.

SFI Fords are especially bad if someone has pressure washed the engine.. :rolleyes:
 

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Usually a pop through the carb is an indication of a lean condition or timing which is extremely advanced. Like X asks is this TBI or a carb? Is the carb the one off your motor or the motor you put in? If it's from the one you put in how long did it sit?

Ditto on double checking all your connections.

PS: I merged your two threads
 

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Discussion Starter #5
xntrik said:
Both TBI,
if it is the same TBI, did you recalibrate computer for the larger engine? It could be LEAN misfire under even slight load.

I think you have multiple unrelated problems.

I would check every connection, clean, tighten prongs for solid grip, and put silicone dielectric grease in every connector.

I've told lots of people out in the field..... multiple symptoms.... check connectors.

SFI Fords are especially bad if someone has pressure washed the engine.. :rolleyes:



well i dont exactly know how to recalibrate the computer system
would you have any ideas on how to do that?

ive cleaned every thing on this engine and all the connectors are good except my intake tempature sensor it melted but that sensor has never once affected it before...

thanks if you you have any other ideas let me know thanks
 

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Discussion Starter #6
engineczar said:
Usually a pop through the carb is an indication of a lean condition or timing which is extremely advanced. Like X asks is this TBI or a carb? Is the carb the one off your motor or the motor you put in? If it's from the one you put in how long did it sit?

Ditto on double checking all your connections.

PS: I merged your two threads

everything is off my old 305 the intake exhaust headers tbi system i thought it was my torque converter at first because once you get the car going after babying it rung alright but you cant mat it down it pops back through the carb im not sure what this thing is doing....

the engine runs amazing at idle i mean not a single miss or anything but as soon as you put it underany kind of a load it runs like a p.o.s
 

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skelly racing said:
well i dont exactly know how to recalibrate the computer system
would you have any ideas on how to do that?

ive cleaned every thing on this engine and all the connectors are good except my intake tempature sensor it melted but that sensor has never once affected it before...

thanks if you you have any other ideas let me know thanks

Does the failed temperature sensor make it read hot or cold? It affects the mixture and timing. Replace it, immediately. "Before" doesn't count. This is a 15% larger engine with 15% more fuel requirements.

Recalibrating a computer fuel/timing map requires a knowledgeable hotrod computer person, or an upgraded computer. I don't know if a plug-in chip is possible.

I'm not sure if you can change just the TBI injectors and make it work or not. I suggest you call Street and Performance in Mena, AR. or go to their website for contact information. They do all SFI stuff.
 

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Discussion Starter #9
timing issues

i swapped the stock 305 tbi outta my 89 camaro and dropped in a 350 tbi

now my timing is completly screwed up, i brought the #1 piston to tdc lined the rotor and cap up and it started right up but as i stuck in gear and when to drive away it stuttered and popped back through the carb and died i used a timing light and it was right on 6 degrees before but it still wouldnt run....

I took and cranked the distibutor as far as i possibly could to the right now it runs half way decent makes tons of power but yet still has a miss in it but nothing serious it still has a hesitation but once up to speed she runs amazing.... i dont get it...

i dont know who built the engine it was in a parts car i had boughten some time ago it has new pistons and rings and connecting rods as far as i can tell
is it possible whoever built the engine installed the cam wrong
 

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Discussion Starter #10
cam and timing problems

is it possible for someone to install a cam wrong if not upside down...
i brought #1 to tdc lined the rotor and cap up perfectly started it and as i put it in either r or d the car would pop back through the carb and die its not 180 i checked after i spun the cap around to the left it began to run great tons of power still hesitates a lil on take off :confused: what could be the cause
is it possible whoever installe the cam installed it wrong
 

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cam is fine, cannot be installed 180 out-impossible,dist was installed at tdc exhaust stroke that is why it was 180 out. need to reset dist in proper position with #1 at tdc compression.
 

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Yes it is possible to install a cam timed incorrectly, at any multiple of 16*, although 180* is also correct, as well as installing a distributor incorrectly positioned.

Lots of cars will run fairly well with 16* retarded cam. I had a factory assembled 383 Mopar that did, and a 2.3 mopar that jumped a cam tooth on the belt and ran fine.

I am wondering if your distributor has turned as far as it can? What is your initial ignition timing now?
 

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sorry I misread thought you said you ended up turning the dist 180 degrees to get it running. Check the timing with a light I bet you got it a tooth off(retarded timing).if it shows this with a light. you will need to lift the dist. and advance it one tooth and reset timing.If you already have the dist turned as far as you can counter clock wise you should just go ahead and do this so you will be able to adjust the timing as needed.
 

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There`s a few things that have to be changed, and since you didn`t mention if you changed them or not I thought I`d add them. Did you change to a 350 ECU? Did you change to the 350 injectors? Did you change to a 350 knock sensor? Far as I know in TBI engines the timing is suppose to be set at 0.
Why these things have to be changed is due to the 350`s 45 more cubic inches of displacement, if it`s still calibrated for a 305 it`ll be too lean on a 350. The knock sensor has to be changed since these operate of frequenceys, since the bore of the 350 is larger than a 305`s, the frequencey is different. If you changed these things already, disregard this post.
 

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If your cam is mis-timed it will NOT show on your ignition timing.

The ignition timing must be "close" to the piston timing for the engine to run, regardless of the cam timing.
 

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Skelly,

I've merged all 4 of your threads which all deal with the same problem. This should make it easier for everyone to follow and will hopefully help to find a solution to your problem.

Bill
 
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