1988 5.7 hardly drives after CL122494 comp cams install

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Slade88

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Hello everyone im new here so please forgive me for any rules I break or mistakes I make. Im so glad I found this sight because I am at an absolute loss right now. I want to turn my daily driver/work truck into a old school hot rod. I have alot of plans for this 88 single cab c1500 but a recent mechanical mishap has left a bad taste in my mouth and im not sure what to do. I decided to do my cam swap first and bought the CL-12-249-4 flat tappet camshaft/lifter kit from comp cams, I made sure this mild cam would work with my mostly stock engine, but I bought some upgrades to install during and after the cam install, a set of z28 valve springs, tiny header spark plugs and super slick tall chrome valve covers complete with breathers. I did everything right and the install went smoothly, I soaked my lifters in high zinc break in oil, i used high zinc break in oil, and I absolutely lathered the cam, lifters faces and distributer gears in assembly lube. I set my timing dots wrong at first, and cranked it for less then 5 seconds before I resolved the issue and set both dots on the timing gears to the 12 o clock position. After I fixed this careless mistake my engine fired right up, I cut it off near in an instant as it was very late and decided to pick up on it in the morning. I fixed all coolant leaks and put out a coolant fire on my headers, they were glowing red hot so as my buddy watched my engine for anything strange I ran it at 2500 rpm then 2800 rpm then 2000 rpm for 10 minutes each with a slight break in between each run to let the headers and engine cool. After this I changed my oil for valvoline sae 30 non detergent oil with a bottle of lucas zinc additive. I cut open my old filter and found a couple specs of metal on each pleat but no "glitter" in the break in oil itself. The engine itself made no unfamiliar noises during the revving and neither did the exhaust, it revved smooth and idles at 950 rpm no surging or anything like that I dont hear any misfiring or popping/lifter tick either. So after a celebration me and my friend decided to take it for a spin, this is where anti climactic disaster struck. My truck felt like it was towing an elephant, very clunky and unresponsive throttle response, it wont rev past 1500 rpm which is strange because it could redline in park. It wont shift to 3rd gear either, and it almost feels like only one of my rear wheels isnt spinning, its that bad, very very sluggish, so much that my top speed was 20 mph. This cam is hardly any bigger then my stock cam, this may sound stupid but I put my hands over my exhaust pipes and they feel like leaf blowers, alot more force then it used to have. So I dont think I wiped my cam, I think this is something else, I have my suspicions but this is my first time ever doing any serious engine work so please forgive me for any stupid thoughts. I never set a timing light on my distributer only set it to fire the #1 cylinder on the compression stroke TDC, i also lost an o ring for my fuel line connection to my TBI unit and kinked up the fuel line hose but straightened it out the best I could, also stripped the TBI aluminum housing and had a bit of a fuel leak but I got it in straight (fuel inlet hole) and screwed it in till it stopped, I noticed that my left fuel pod was spraying about half way and dripping drops of fuel which im sure isnt good. I have been told it may be running lean with load or may be trans problem due to a vacuum problem? I also deleted both vacuum lines coming out of my valve covers and replaced them with oil breathers could this be the problem? I have no idea whats going on this is my daily driver so any help would be greatly appreciated!
 

BOOT

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Ok first a posting tip, break it up some so it's easier for people to read/skim thru it.

For example....

"Hello everyone im new here so please forgive me for any rules I break or mistakes I make. Im so glad I found this sight because I am at an absolute loss right now. I want to turn my daily driver/work truck into a old school hot rod.

I have alot of plans for this 88 single cab c1500 but a recent mechanical mishap has left a bad taste in my mouth and im not sure what to do. I decided to do my cam swap first and bought the CL-12-249-4 flat tappet camshaft/lifter kit from comp cams, I made sure this mild cam would work with my mostly stock engine, but I bought some upgrades to install during and after the cam install, a set of z28 valve springs, tiny header spark plugs and super slick tall chrome valve covers complete with breathers. I did everything right and the install went smoothly, I soaked my lifters in high zinc break in oil, i used high zinc break in oil, and I absolutely lathered the cam, lifters faces and distributer gears in assembly lube.

I set my timing dots wrong at first, and cranked it for less then 5 seconds before I resolved the issue and set both dots on the timing gears to the 12 o clock position. After I fixed this careless mistake my engine fired right up, I cut it off near in an instant as it was very late and decided to pick up on it in the morning.

I fixed all coolant leaks and put out a coolant fire on my headers, they were glowing red hot so as my buddy watched my engine for anything strange I ran it at 2500 rpm then 2800 rpm then 2000 rpm for 10 minutes each with a slight break in between each run to let the headers and engine cool.

After this I changed my oil for valvoline sae 30 non detergent oil with a bottle of lucas zinc additive. I cut open my old filter and found a couple specs of metal on each pleat but no "glitter" in the break in oil itself. The engine itself made no unfamiliar noises during the revving and neither did the exhaust, it revved smooth and idles at 950 rpm no surging or anything like that I dont hear any misfiring or popping/lifter tick either.

So after a celebration me and my friend decided to take it for a spin, this is where anti climactic disaster struck. My truck felt like it was towing an elephant, very clunky and unresponsive throttle response, it wont rev past 1500 rpm which is strange because it could redline in park. It wont shift to 3rd gear either, and it almost feels like only one of my rear wheels isnt spinning, its that bad, very very sluggish, so much that my top speed was 20 mph.

This cam is hardly any bigger then my stock cam, this may sound stupid but I put my hands over my exhaust pipes and they feel like leaf blowers, alot more force then it used to have. So I dont think I wiped my cam, I think this is something else, I have my suspicions but this is my first time ever doing any serious engine work so please forgive me for any stupid thoughts. I never set a timing light on my distributer only set it to fire the #1 cylinder on the compression stroke TDC,

i also lost an o ring for my fuel line connection to my TBI unit and kinked up the fuel line hose but straightened it out the best I could, also stripped the TBI aluminum housing and had a bit of a fuel leak but I got it in straight (fuel inlet hole) and screwed it in till it stopped, I noticed that my left fuel pod was spraying about half way and dripping drops of fuel which im sure isnt good.

I have been told it may be running lean with load or may be trans problem due to a vacuum problem? I also deleted both vacuum lines coming out of my valve covers and replaced them with oil breathers could this be the problem? I have no idea whats going on this is my daily driver so any help would be greatly appreciated!"
 

BOOT

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There are obviously a lot of things that could of went wrong, some even unrelated to the cam swap, for example the trans maybe overheated. Did you check the fluid level, hook up the trans lines or damaged them?

Did you forget to hook up the TV cable? Or change brackets, replace the cable mess with it or anything like that?
 

Donald Mitchell

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My thought would be to check valve lash and timing again.
put out a coolant fire on my headers, they were glowing red hot
I have no idea what a coolant fire is but red hot headers is kind of extreme when breaking in an engine.
 

evilunclegrimace

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My thought would be to check valve lash and timing again.

I have no idea what a coolant fire is but red hot headers is kind of extreme when breaking in an engine.
Antifreeze can catch fire and burn once it reaches 650-750 degrees due to the Glycol content.
 

dave s

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Yeah I agree with everything said so far. This is one of those issues where you wished the guy lived close so you could physically lend a hand. I'm sure by end of day though this thread will be pages long with some very good ideas on what to check.

Timing comes to mind first to me. The red hot header would be a flag. I've only rebuilt two Chevy motors but I didn't get red hot headers breaking them in. Did you unplug the brown striped wire and set base timing?

I'm really at a loss about the drivability part though. If it drove just fine before the cam swap I'd be looking for something left unplugged or not connected. Wish I could offer you some better ideas but you need to start with basics and just eliminate things one at a time. I'll be watching this thread. Please post up once you get it fixed so we know what it was. Good luck.
 

DerekTheGreat

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I'm not an engine builder, but I'd verify and then check timing. I wouldn't be surprised if it's pretty retarded. Also, I don't know what the cam's specs are (nor am I that knowledgeable about them either) but changing the cam & then expecting the stock EFI to work properly & deliver the right amount of fuel is like eating raw chicken and hoping you don't get sick.
 

Erik the Awful

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My truck felt like it was towing an elephant, very clunky and unresponsive throttle response, it wont rev past 1500 rpm
Does it still rev fine in park?

You state this is your daily driver, so I assume that before the cam swap it drove well?

Jack it up and make sure the rear wheels turn by hand. If it's a brake issue, you don't want to be tearing down the engine to try and find it. I had a leaky rear wheel cylinder, and after I replaced it I didn't get all the gunk out of the drum assembly. My right rear wheel nearly locked up the truck a hundred yards from my house.

Definitely fix any issues with your TBI.
 

GoToGuy

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If you by any chance, changed or did not do a trans TV cable check that will affect trans operation.
The whole condition sounds like you have multiple overlapping issues. Are you checking your work and following provided install instructions. Use GM service manual for standard procedures. Twice in forty plus years I saw headers, exhaust manifold cherry red on start/ idle the ignition/ firing order screwed up. That was scary, holy *****. That was then, neighbor's kid. Just one problem it could be. Good luck.
 
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