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tom_sprecher
07-05-2007, 08:41 AM
I'm just about done buiding the car and took my 1st gen for a test drive. It starts fine but does not want to run for more than a minute or even less unless I stay on the gas pretty hard and even then it loses power and will die most times. The fuel is about in the middle of the float level sight glass on both bowls. It got hot real quick and the header was glowing red hot.

The motor came out of my last car and was running fine right up to when I hit a wall. It has sat on a stand in my garage for the last 17 months. Does this sould like a lean condition or what could it be?

Speed Raycer
07-05-2007, 09:02 AM
Sounds like an extreme lean condition to me... you might check to see if your intake manifold cracked when you hit the wall.... I cracked an intake manifold once and it would start and run but as soon as you gave it some gas the header would start glowing and it ran terrible.

lateapex911
07-05-2007, 09:37 AM
Of course, check the carb as well, if you can swap a carb, ( 5 minute job) that helps to eliminate that possibility quickly. Double check the timing too.

JeffYoung
07-05-2007, 11:57 AM
Jake! That back right nut on a 1st gen carb is NOT a five minute job! LOL...I remember the first time I took the carb off on my street car back in 94 (might have been teh first time I ever got my hands dirty on a car) to fix the shutter valve. Took me all day to do it....damn....

crushed
07-05-2007, 01:46 PM
fuel filters maybe? but if the bowls are staying full the entire time that can't be it. It sounds to me like it could be a vacuum leak somewhere downstream of the carb like Scott is saying. I have a spare carb ready to go if you want to swap yours out...

lateapex911
07-05-2007, 03:29 PM
LOL, Jeff, thats the ONE job I can actually do in 5 minutes on my car*. Remember, all that emissions crap is gone, and theres real room to get at things. Oh, and one of theose little ratcheting box wrenches spins that sucker off in 40 seconds. You DO have a set of those, dontcha!? ;)

* My carb was built by a certain prominent carb builder, and he invited me to send it back for service when it developed major issues...100 calls later, almost two years of waiting, and I've been "borrowing" carbs since. Still no call back, and no carb. I ran last years ARRC and ProIT races on a 100% never opened stock carb.

Thanks to Grant McStay for the loan of his, and Dick Patullo for the loan of his as well. Dick, I'm retapping the thing as we speak, I haven't forgotten about you buddy!

C. Ludwig
07-05-2007, 08:14 PM
Retarded timing can cause high exhaust temps and create the glowing header. The fuel will literally burn in the exhaust. That's part of the premise behind anti-lag systems on turbo cars. Double check the timing.

tom_sprecher
07-06-2007, 08:37 AM
Thanks for the replies and when I get back from vacation I'll try anything you guys suggest that will get me on the track for test day at Road Atlanta on the 20th.

Ron Earp
07-06-2007, 11:14 AM
Double what Chris said, ignition timing. Put some dizzys in a few gear teeth off trying get a motor into rough timing to run and ended up retarded, severely, with glowing manifold.

R

dyoungre
07-06-2007, 02:29 PM
I did a whole race last year on secondary timing only! I lost the primary coil ignitor on the warm up lap, and didn't notice the total loss of power until the start. By the end of the race, my feet were on fire, and my muffler worked loose due to the heat.

I have a Uego, and could watch it throughout stay right around 13:1. Once I got the ignitor back running, everything was back to normal.

tom_sprecher
07-06-2007, 09:52 PM
Much thanks to you guys and after reading some of these posts I would like to make some comments and see what you think.

1. The distributor was not removed or even touched for that matter. I'm not saying it could not have moved but there would be evidence where the nut clamps the slotted plate down to the block.

2. I did replace some of the vacuum block offs on the carb and may have left one off or one fell off because it was not clamped.

3. Although I did draw up two schematics of the ignition wiring there was some conflict between the two (probably due to looking at wiring through beer goggles) and one of the old coils that got smashed did not have a + or - terminal, instead one was labeled "15" and the other had nothing. So it could very well be that the coils are wired incorrectly.

It will be a week before I can try some of your suggestions but please keep them coming as it helps to narrow down the possibilities.

Thanks again,

tom_sprecher
07-16-2007, 03:17 PM
The ignition was wired correctly, there was no vacuum leak and the timimg was not retarded, but I must have been when I plumbed the Holley FPR ass backwards. :blink:

Car starts, runs and idles fine and no more red hot headers. :happy204:

Thanks for all the suggestions as they really helped me out. :023:

joeg
07-16-2007, 04:42 PM
I always thought Rotarys stood for exhaust barbeque!