need a little TBI help
#1
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Car: 92 GMC K2500 LD
Engine: 350 TBI with some mods
Transmission: NV4500
Axle/Gears: 3.73
need a little TBI help
Hey Guys.
I just did an engine swap on a TBI truck 92 model. The engine was a rebuild out of an 88. While the engine was out I changed the cam, lifters and chain, CS1014R RV cam. Edelbrock TBI Manifold, 15lb regulator spring, new throttle body (stock), I put a Harris performance chip in it.
Anyway I got it started up but it is running like crap and over heating. I had some issues getting it to fire up (dist was 180 out) but after that it fired right up running a bit rough but not bad. I pulled the advance wire and set the timing to 0. I plugged it back it and attempted to seat in my cam. It ran a few minutes and started over heating. I tried burping it. It wouldn't even idle without over heating. I pulled the tstat and drilled a 1/8" bleed hole, jacked the front end up. I finally got it so where it would run about 240 at idle. As soon as I shut it down and give it a few minutes it cools right down to 120 (like I have an air pocket) I am getting good flow through the radiator and even pulled the temp sender out to make sure there wasn't air. I put the stock prom back in with no difference.
It is also running very bad. It labors to get to 3k rpm and backfires through the exhaust when I let off. Its running a little rough and very slow to respond. I took it down my driveway and it has no power at all. I pulled the valve covers and adjusted the valves, rechecked the plug wires and rechecked the timing. I am running out of things to check.
Thanks for the help.
I just did an engine swap on a TBI truck 92 model. The engine was a rebuild out of an 88. While the engine was out I changed the cam, lifters and chain, CS1014R RV cam. Edelbrock TBI Manifold, 15lb regulator spring, new throttle body (stock), I put a Harris performance chip in it.
Anyway I got it started up but it is running like crap and over heating. I had some issues getting it to fire up (dist was 180 out) but after that it fired right up running a bit rough but not bad. I pulled the advance wire and set the timing to 0. I plugged it back it and attempted to seat in my cam. It ran a few minutes and started over heating. I tried burping it. It wouldn't even idle without over heating. I pulled the tstat and drilled a 1/8" bleed hole, jacked the front end up. I finally got it so where it would run about 240 at idle. As soon as I shut it down and give it a few minutes it cools right down to 120 (like I have an air pocket) I am getting good flow through the radiator and even pulled the temp sender out to make sure there wasn't air. I put the stock prom back in with no difference.
It is also running very bad. It labors to get to 3k rpm and backfires through the exhaust when I let off. Its running a little rough and very slow to respond. I took it down my driveway and it has no power at all. I pulled the valve covers and adjusted the valves, rechecked the plug wires and rechecked the timing. I am running out of things to check.
Thanks for the help.
#2
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Car: 75 Beast
Engine: 383 +EBL Flash
Transmission: 700R4
Axle/Gears: 4.11 with 33"
Re: need a little TBI help
I run CS1014R in my newer 350 engine that I dropped in over the XMAS break. It should run like a champ as it is very TBI friendly cam shaft. I assume that you are not running super high compression pistons and used correct head gasket. If you do not mind list your engine particulars.
To get around a possibility of air pocket in a fresh engine I remove t-stat and poor coolant into intake (with radiator filler open). This allows coolant to fill engine block and heads slowly - forcing air pockets. I also run heater hose from intake manifold into radiator - this will by pass t-stat and will purge air out.
Assuming that all other things are correct check spark-plug wires - make sure that all cylinders are firing. A swapped cylinder pair is a common problem - this will cause rich condition (extra oxygen dumped into exhaust along with un-burnt fuel).
//RF
To get around a possibility of air pocket in a fresh engine I remove t-stat and poor coolant into intake (with radiator filler open). This allows coolant to fill engine block and heads slowly - forcing air pockets. I also run heater hose from intake manifold into radiator - this will by pass t-stat and will purge air out.
Assuming that all other things are correct check spark-plug wires - make sure that all cylinders are firing. A swapped cylinder pair is a common problem - this will cause rich condition (extra oxygen dumped into exhaust along with un-burnt fuel).
//RF
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Car: 92 GMC K2500 LD
Engine: 350 TBI with some mods
Transmission: NV4500
Axle/Gears: 3.73
Re: need a little TBI help
Thanks RF,
I figured out one of my problems. One of my injectors wasn't firing. I had sent them off to get tested and cleaned. I need to get on the phone and get on someone. I swapped it out with another injector and that thing came alive. It ran like a scalded dog. I am still over heating but I am going to try getting a delco sensor and see if that helps. The amount I have circulated through should taken care of any air pockets.
I figured out one of my problems. One of my injectors wasn't firing. I had sent them off to get tested and cleaned. I need to get on the phone and get on someone. I swapped it out with another injector and that thing came alive. It ran like a scalded dog. I am still over heating but I am going to try getting a delco sensor and see if that helps. The amount I have circulated through should taken care of any air pockets.
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Car: 92 GMC K2500 LD
Engine: 350 TBI with some mods
Transmission: NV4500
Axle/Gears: 3.73
Re: need a little TBI help
I put a delco temp sensor in it and all my temp problems vanished except now I think my bleed hole is allowing too much flow with the cooler weather. Oh well if it isnt one thing it is another. But overall I am happy with it. It runs like a champ now.
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Car: 75 Beast
Engine: 383 +EBL Flash
Transmission: 700R4
Axle/Gears: 4.11 with 33"
Re: need a little TBI help
//RF
#6
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Car: 92 GMC K2500 LD
Engine: 350 TBI with some mods
Transmission: NV4500
Axle/Gears: 3.73
Re: need a little TBI help
Yep sometimes it is worth the few bucks extra buy delco stuff.
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