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70 rr heatsoak/vaporlock problem

TRAMO

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having a big problem with heat soak/vaporlock on my 70rr that has just been put back on the rd.i have been trying to fix this for 3 months.its a 383 with a little above stock cam.edelbrock 1406 carb.factory hp manifolds,air grabber hood. starts and runs great .no engine overheat problems.has a 160 stat in it.3 row radiator.but after you drive it until it reaches operating temp and cut the engine it will not start un til the engine cools down some.i put a .500 phenolic spacer on it andit helped a little.im wondering if the edelbrock carb might be the problem.i have heard that is a common problem with them ,or could it be the timing ,its set about 10btc.im thinkink about putting intake gaskets that block the heat crossover. any and all suggestions would be appreciated. IMG_2065.jpg
 
Blocking the crossover does help, especially in the warmer locations. Maybe a return line to the tank would help, we did that and it made a world of difference.
 
Blocking the cross over is a must and probably the majority of the issue. 10 degrees initial is only making it worse. I'd add 10 to start and see how that does. Keep total to about 35. Put the off road needle/seat assembly in that carb (it helps when corning) and keep the fuel pressure down to 6 or less.
 
I had to recently reduce the spacer on my carb and used this it seems to be working.

http://www.summitracing.com/parts/mrg-757


With todays gas having a lot of ethanol it evaporates quicker keeping the carb cool helps a lot. raising a stock set you creates hood clearance issues so this spacer works for that. Try to make sure your tank vents are working and have a non vented gas cap and your fuel lines are new and of good aftermarket quality.


20140621_094916.jpg
 
having a big problem with heat soak/vaporlock on my 70rr that has just been put back on the rd.i have been trying to fix this for 3 months.its a 383 with a little above stock cam.edelbrock 1406 carb.factory hp manifolds,air grabber hood. starts and runs great .no engine overheat problems.has a 160 stat in it.3 row radiator.but after you drive it until it reaches operating temp and cut the engine it will not start un til the engine cools down some.i put a .500 phenolic spacer on it andit helped a little.im wondering if the edelbrock carb might be the problem.i have heard that is a common problem with them ,or could it be the timing ,its set about 10btc.im thinkink about putting intake gaskets that block the heat crossover. any and all suggestions would be appreciated.

I ran into the same stuff after I got my car back on the road, same setup except I have headers, a 180 stat and an 1806 carb. I would say go ahead and install the valley pan with the exhaust blockoffs, no need for the extra heat and it only costs $15.

When you say it wont restart, does it act like the battery is dead? Or does it just turn over and over like normal but with no fire.
 
I ran into the same stuff after I got my car back on the road, same setup except I have headers, a 180 stat and an 1806 carb. I would say go ahead and install the valley pan with the exhaust blockoffs, no need for the extra heat and it only costs $15.

When you say it wont restart, does it act like the battery is dead? Or does it just turn over and over like normal but with no fire.
TURNS OVER AND OVER FINE.JUST WONT START.where can ig et that 15 dollar gasket? thanx randy
 
TURNS OVER AND OVER FINE.JUST WONT START.where can ig et that 15 dollar gasket? thanx randy

http://www.jegs.com/i/Fel-Pro/375/1215/10002/-1

http://www.summitracing.com/parts/fel-1215

Sorry they are more than $15, I realized the felpros for that price dont have the passages blocked. You can usually use just the bathtub on its own with iron intakes/iron heads.

Will it start with the pedal to the floor? Try that next time and don't pump the gas. If no go, it should then fire on ether or gas poured in the carb to get things moving along.

Where is your fuel filter? an inline canister filter on top of the engine can get vapor build up inside. Try running a filter at the fuel tank only and see if the hot start improves.

Reroute all the lines away from the exhaust. If no luck, might start planning to install a return line. It's worth the trouble. I basically have the a12 setup with 1/4" steel return along the passenger side frame but you can use braided or tube as well. Plumbing in the return line was the trump card for my car.
 
Had the same problem with the exact carb.I have the cross over blocked and had a Cool Carb spacer.Took the spacer and the Edelbrock carb off and put a Holley 670 street avenger on and problem solved.
 
ok guys, i think i might have found the biggest part of the problem.i put a 15.00 standard ig. coil on it and it starts 99% percent better when operating temp.it will start in3 or 4 seconds now.it dont start by bumping the starter i have to pat the pedal a little to start when warmed. what coil should i put on it permenantly. the ignition system is a mopar performance electronic ig. kit modelp3690427.
 
ok guys, i think i might have found the biggest part of the problem.i put a 15.00 standard ig. coil on it and it starts 99% percent better when operating temp.it will start in3 or 4 seconds now.it dont start by bumping the starter i have to pat the pedal a little to start when warmed. what coil should i put on it permenantly. the ignition system is a mopar performance electronic ig. kit modelp3690427.

msd blaster 2 with a 0.8ohm ballast is a good combo, you can get both from msd. Keep your stock coil and ballast as a spare.
 
somebody educate me a little.what would be the difference in spark/running between a stock ig. coil and a performance coil?i here some say it would run no different. i would like to keep the coil looking similar to stock by painting it.
 
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