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#21
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you are probably loosing ignition, if it fires and when you get off the starter button it dies, if i read your post right.
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1963 Cat SD Clone (old school) streeter 1964 GTO post coupe, tripower, 4speed (build) 1965 GTO 389 tripower, 4 speed, driver 1966 GTO dragcar 1966 GTO Ragtop 1969 Tempest ET clone street/strip 1969 GTO Judge RA lll, auto 1969 GTO limelight Conv. 4speed go and show (sold) 1970 GP SSJ 1970 GTO barn find..TLB…390 horse?….yeh, 390 1972 GTO 455 HO, 4 speed, (build) 1973 Grand Safari wagon, 700hp stoplight sleeper 525ci DCI & 609ci LM V head builds |
#22
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X3 may not backfire if it is not running long enough.
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#23
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Okay. It will be Thursday when I can work on it again. Thanks for the replies I'll let you know.
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#24
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Not to insult your intelligence, but did you verify you are on the compression stroke by pulling the valve covers when installing the dist.?
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#25
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You wouldn't be insulting my intelligence,just my engine knowledge. I know how to do what you're talking about, but no I haven't done it. The way it runs made me think it couldnt be that. In the past when I've had one 180 out it let me know as soon as it fired. This one has no miss or backfire. Though 10 or 15 seconds is the longest it has run. It just kind of peters out.
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#26
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Go back to the basics. Timing - ignition and cam, fuel, compression, air. Test these 1 at a time until you find the issue.
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#27
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1st take the #1 plug out, rotate the engine by hand, put your finger by the hole, when it puffs,pushes your finger out, stop and see where the rotor is pointing.
It should be pointing at the #1 post on the cap. Go from there.
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John Wallace - johnta1 Pontiac Power RULES !!! www.wallaceracing.com Winner of Top Class at Pontiac Nationals, 2004 Cordova Winner of Quick 16 At Ames 2004 Pontiac Tripower Nats KRE's MR-1 - 1st 5 second Pontiac block ever! "Every man has a right to his own opinion, but no man has a right to be wrong in his facts." "People demand freedom of speech to make up for the freedom of thought which they avoid." – Socrates |
#28
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it wouldnt run 10-15 seconds if the timing were 180 out. I think either your timing is retarded too much, serious vacuum leak. Even though you have tried 2 carbs, I would borrow a KNOWN good carb off of a running vehicle and try it.
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70 Formula Old engine: 467 HO headed 6.79 1/8th mile @ 101.87 no N20. 1.44 60ft 6.23 1/8th @ 111.83 w/nitrous 1.37 60ft New Engine IAII 535 Calvin Hill Eheads Few test passes made. Tore it up. Just got it fixed. |
#29
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I had a very similar issue with the first Pontiac motor I assembled. I did not notice that the aftermarket valley pan I used wasn't letting the intake set correctly against the heads. I had a vac leak at the intake to head on all 4 runners on the driver side. I ordered a thicker intake gasket and problem was solved.
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79 TA 476, Single 88MM turbo Street car. Pump gas, Radial tires, Full exhaust, 4000 LB race weight Best 1/4 1.39 60 ft 9.03@149.55 Last edited by 7D9TA; 12-30-2012 at 11:03 AM. Reason: spelling |
#30
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you can also run the timing light when you are turning it over and see where its at and if its firing all the time too
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www.bowhanger.com 468 poncho powered 66 cutlass 77 Trans http://s1059.beta.photobucket.com/us...rnout.mp4.html |
#31
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When you have someone start the engine, put your hand over the primary side of the carb so you hand acts like a choke shutting off most of the air to the engine. If it keeps running then you have a vacuum leak. Plug all the vacuum ports of the engine and the carb and try it again. If you have to leave your hand on top of the carb to keep it running then you have either vacuum leak at the intake gaskets, an intake valve too tight or a leak at the carb.
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Go Fast... Return... Go Fast Again... Who cares about left turns??? |
#32
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John, that's the way I've always done it. And it's been reset that way at least 4 times. But I'm going to pull the valve cover Thursday to make sure. I have 2 dominators, both are rebuilt but neither is proven. I'm going to order an adapter and use a known 850 I have. Then if not fixed I'll start trying to track vacuum leaks.
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#33
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if it's ran for 15 seconds, you're not 180 out. however, if you want to check, pull the pass side valve cover and put #6 into overlap. at this point the balancer should be close to zero, and #1 at tdc compression. check your dist to see where it's pointed.
I think it's fuel related, it shouldn't run for 15 seconds with a poor electrical connection. what is your fuel pressure while it's running? this sounds like a simple problem that you'll give yourself a face palm over once you find it. |
#34
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check voltage to fuel pump when you have it running for a few seconds, or drizzle fuel into carb to determine if it electrical or fuel issue. If it stays running when fuel(or starting fluid) is being introduced, you can quit looking at electrical issues.
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#35
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Quote:
GT. |
#36
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like no juice in the run position of the ignition swi...
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1977 Black Trans Am 180 HP Auto, essentially base model T/A. I'm the original owner, purchased May 7, 1977. Shut it off Shut it off Buddy, I just shut your Prius down... |
#37
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Yep; It almost sounds like when you let off the key it looses spark. GT. |
#38
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Did you change the firing order on your cam? (4-7 swap) Do the plug wires match the firing order. I know that sounds stupid but sometimes we can overlook the simplist things.
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James 1970 Trans Am Spotts Built 484" IA2, Highports, EFI Northwind Holley Terminator X sequential EFI fabrication and suspension by https://www.funkhouserracecars.com/ |
#39
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Quote:
If you're still using a key switch it could be just a bad switch. I'd run a new wire to the ignition box/dist and try again. I hope its something simple. |
#40
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If the car has the lock cyl in the column, w/ the ign. swi. on the column.......... Have you fooled w/ the column lately??? The electrical part of the switch could be out of adjustment, a hair, and do this, I HATE working on those... I pull the drivers seat out so I can get to the switch easier, only way to work on it....
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1977 Black Trans Am 180 HP Auto, essentially base model T/A. I'm the original owner, purchased May 7, 1977. Shut it off Shut it off Buddy, I just shut your Prius down... |
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