What's wrong with my stroker....
Thread Starter
Instructor
Joined: Feb 1999
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What's wrong with my stroker....
Here's a question for all you tuners. When my engine is cold, it makes tons of power. When it warms up, the power drops off noticably. I am about to start troubleshooting and am looking at the following:
-valve recession? I had this issue early with this engine. after a couple of thousand miles, it would not idle when warm. After a ton of fiddling with the carb, I finally set the valves. About 8 of them where tight. Ran fine afterwards. It has about 5000 miles on it now.
-too lean? Could be with a little electric choke still on it runs richer. But, the plugs look good, so...?
-Something else?
Any ideas? For reference, this is a 383, flatops, 2.02 heads, Q-jet re-jetted and de-environmentalized, electric choke, cam a little wilder than a 350/350HP. 2-1/2 exhast all the way back and a TH400 auto with a stage 1 shift kit.
The difference between cold and hot is significant. Cold, it will light the back tires and spin through the 1-2 shift at 2/3 throttle. at about 180 degrees, power seems to tail off a bit. warm, at 200 degrees it won't spin the tires at WOT. Feels like about a second difference in the quarter.
Lee
-valve recession? I had this issue early with this engine. after a couple of thousand miles, it would not idle when warm. After a ton of fiddling with the carb, I finally set the valves. About 8 of them where tight. Ran fine afterwards. It has about 5000 miles on it now.
-too lean? Could be with a little electric choke still on it runs richer. But, the plugs look good, so...?
-Something else?
Any ideas? For reference, this is a 383, flatops, 2.02 heads, Q-jet re-jetted and de-environmentalized, electric choke, cam a little wilder than a 350/350HP. 2-1/2 exhast all the way back and a TH400 auto with a stage 1 shift kit.
The difference between cold and hot is significant. Cold, it will light the back tires and spin through the 1-2 shift at 2/3 throttle. at about 180 degrees, power seems to tail off a bit. warm, at 200 degrees it won't spin the tires at WOT. Feels like about a second difference in the quarter.
Lee
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Joined: Sep 2002
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From: San Diego - Deep Within The State of CONFUSION!
Originally Posted by Lee
electric choke still on it runs richer. But, the plugs look good, so...?
<<SNIP>>
The difference between cold and hot is significant. Cold, it will light the back tires and spin through the 1-2 shift at 2/3 throttle. at about 180 degrees, power seems to tail off a bit. warm, at 200 degrees it won't spin the tires at WOT.
Lee
<<SNIP>>
The difference between cold and hot is significant. Cold, it will light the back tires and spin through the 1-2 shift at 2/3 throttle. at about 180 degrees, power seems to tail off a bit. warm, at 200 degrees it won't spin the tires at WOT.
Lee
Thread Starter
Instructor
Joined: Feb 1999
Posts: 134
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Distributor is ,I believe, an HEI from a 454 truck , it was recurved, but I don't know the specific details on what was done to it. No change there that I know of. I have not checked float level, but I will.
Good questions, but I am not sure how that would affect cold versus hot performance.
Lee
Good questions, but I am not sure how that would affect cold versus hot performance.
Lee
Instructor
Joined: Sep 2001
Posts: 209
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From: Seattle WA
I have the same issue now, causd by lack of cold air intake. My EFI takes in ambient air temperature when its cold, and 200 degree air when it gets all warmed up. Hot air is much less dense. The solution is to fabricate a cold air intake system.
Cheers!
Cheers!
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Joined: Sep 2004
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
are yu sure you have adequate fuel pressure, sounds like a fuel starvation problem, either float or blocked filter, debris in your line blocking the feed. etc...
