Problems with new engine...
Race Director
Joined: Feb 2002
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From: Compound in the Grove, Ga.
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St. Jude Donor '16
I agree with the injector also 28# to 30# and a good tune after you get the fuel pressure taken care of.
Melting Slicks
Joined: Jan 2009
Posts: 3,482
Likes: 196
From: folsom california
Well, definitely need to get that fuel system in line. Should be around 42 psi give or take.
Checked out your link to the other thread about the engine. I'm really wondering about the 42# injectors. This is not my field of expertise, but looking at the build, it doesn't really look like anything that requires that much fuel. Considering that the stock LT1 came with 22's or 24's and even the LT4 had 28's. The unknown of course is the cam specs, but could you be actually dumping too much fuel into the cylinder on acceleration and it stumbles until the A/F ratios can catch up? I don't know, it just seems that huge injector for a 355 build, anyone chime in?
Checked out your link to the other thread about the engine. I'm really wondering about the 42# injectors. This is not my field of expertise, but looking at the build, it doesn't really look like anything that requires that much fuel. Considering that the stock LT1 came with 22's or 24's and even the LT4 had 28's. The unknown of course is the cam specs, but could you be actually dumping too much fuel into the cylinder on acceleration and it stumbles until the A/F ratios can catch up? I don't know, it just seems that huge injector for a 355 build, anyone chime in?
Thread Starter
Instructor
Joined: Feb 2011
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Well... I have great news. I have finally after all my post and threads figured out what the problem is on my corvette. For those who have been following since the beginning it was none of the things listed before. The problem was the shop that rebuilt my engine accidentally swapped the o2 sensors! The car was leaning out! Even with my huge injectors there is nothing wrong with my fuel delivery.
I took it to "Corvette specialty" a shop that only works on corvettes and they figured it out real quick. They cost a ton but I lucked out with only 2 hours labor. The engine runs like a friggen champ. I am going to slap on my 1.6 roller rockers and my Ignition timing module and begin work on the body/paint.
Now I have two more problem to work out. Its happened 3 times now.
When I pull real hard on the car and hit redline or close to it, i lose all throttle response. The car pulls great until i lay off the throttle and shift then i stomp back on the throttle and nothing. I still get resistance from the throttle but it feels almost like its stalled out but it is still running. I get nothing until the RPMs run down and then bam the engine is back to life like nothing happened. What could this possibly be?
My second problem is my brakes. When the car heats up past 210 degrees (like if i am stuck at a light on a hot day) I instantly lose all brakes. the petal goes straight to the floor, no resistance. I am thoroughly convinced I have an air bubble in the line and when it gets really hot the bubble boils/vaporized and I can't make any compression in the line. I am going to bleed the brakes this weekend but I thought i would run this by you guys first to see if you have heard of this happening before. I first though the booster line was loosing vacuum but i've checked it out and its solid.
I took it to "Corvette specialty" a shop that only works on corvettes and they figured it out real quick. They cost a ton but I lucked out with only 2 hours labor. The engine runs like a friggen champ. I am going to slap on my 1.6 roller rockers and my Ignition timing module and begin work on the body/paint.
Now I have two more problem to work out. Its happened 3 times now.
When I pull real hard on the car and hit redline or close to it, i lose all throttle response. The car pulls great until i lay off the throttle and shift then i stomp back on the throttle and nothing. I still get resistance from the throttle but it feels almost like its stalled out but it is still running. I get nothing until the RPMs run down and then bam the engine is back to life like nothing happened. What could this possibly be?
My second problem is my brakes. When the car heats up past 210 degrees (like if i am stuck at a light on a hot day) I instantly lose all brakes. the petal goes straight to the floor, no resistance. I am thoroughly convinced I have an air bubble in the line and when it gets really hot the bubble boils/vaporized and I can't make any compression in the line. I am going to bleed the brakes this weekend but I thought i would run this by you guys first to see if you have heard of this happening before. I first though the booster line was loosing vacuum but i've checked it out and its solid.
Last edited by twentyeggs; Feb 18, 2014 at 07:52 PM.
