Overheating 57 dual quads
For as long as I can remember, the dual quads (WCFB) on my 57 have had a problem over overheating and boilout/dryup after running hard. Also, when sitting overnite after a run like this, it car takes awhile to start. I presume this is the time to refill the carbs. This setup does not have any spacer (just a gasket) between the carbs and the intake manifold. It was suggested that I install a phenolic or other plastic spacer between the carbs and the manifold to lessen the heat soak/transfer. I recall that Chrysler's 4 bbl carbs had such a plastic spacer. Has anyone on the forum any experience in using a spacer on 57's and WCFB's in particular? I noticed that the parts books show one for the '62 but not the 57. Comments/advice welcome.
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Re: Overheating 57 dual quads
did you ever pull the intake and check the condition of the manifold itself,sounds to me there is an issue with heat from below, possibly blocking offthe heat runner on the intake gaskets? good luck, have ran a number of your setup and never ran across such an issue -
Re: Overheating 57 dual quads
I too have had a number of dual quad setups back in the day. Mine were on passenger cars with lots of under hood clearance. Your 57 Vette is too tight to employ much of a spacer under the carbs. I would check the manifold and block off the exhaust heat passages as suggested.Stu FoxComment
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Re: Overheating 57 dual quads
Thanks for the comments guys, but as I recall, the manifold heat riser holes are not there. Just the casting. Suspect this is why. I just rebuilt the engine 3 years ago. It has always done this to some extent but it seems worse now. TedComment
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Re: Overheating 57 dual quads
Michael thanks for the reply. I am using 91 Octane unleaded but I am sure it is laced with ethanol. I have had the ethanol give me vapor lock years ago. You mentioned to insulate the carbs. Actually, that was the start of the thread. I was looking for someone who had experience with this and also with the WCFB's I know clearance is a problem but I think the old thermoquad that Carter made for Chrysler had such a system but I could be wrong. Perhaps it was a phenolic fuel bowl. Anyway, insulating it was what I was looking for. TedComment
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Re: Overheating 57 dual quads
Ted;Check your hood clearance to the air cleaners using some kind of crushible clay set on top of the highest point. I know you can get spacers at 1/4" made of a fiberboard material. I used 5 of them back in my racing days with the cross cuts cut out in order to pack up charge for the two lean cylinders at WOT, but your application won't allow that. I'd try at least lowering the floats a bit. Look for a gas station that carries non-ethanol gas, usually found around inland lakes where guy's with older boats still need it. That's what I did here in Florida, but of course all you can get is 90 Octane. But, your 9.5 to 1 comp ratio should be ok perhaps with a little retard on the timing. I use Maxlead 2000 as mine is rated at 11.5 to 1, so I try for a final of 100 Octane. Also, with WCFB's, make sure your floats don't drag on the sides. Do you have your heat riser butterfly in place? If so, you might try wiring it open for the summer at least.Stu FoxComment
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Re: Overheating 57 dual quads
Ted, To find ethanol free gas google: Pure-gas.orgThen click on your state and there will be a list of stations that sell pure gas. Try some 100LL aviation fuel or racing fuel and see if this helps resolve the problem. JohnComment
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Re: Overheating 57 dual quads
Ted -
If you have the stock 653 intake manifold and 997 heads, both have the heat riser exhaust crossover passages; with E10 gas that boils at 150*F, they should be blocked (and the heat riser valve either wired open or replaced with the F.I. spacer).Comment
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Re: Overheating 57 dual quads
Ted, John is correct. Back in the 60's when I used to regularly take the '57 2X4 out for drives of 100+ kicking in the second WCFB it was common to heat up and take 15-30 minutes setting to start again. The crossover passage blockoff did the trick. SteveComment
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Re: Overheating 57 dual quads
Nothing sounds more impressive as a Vette or Chevy with dual quads and loud pipes than to kick in the 2 stage progressive linkage under a street viaduct. We had a perfect place for that in Racine, WI back in the day.
Stu FoxComment
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Re: Overheating 57 dual quads
Yep, Steve used to do that. I used the heat riser block offs when I put the 2X4s back on my '59 also. I also don't have an exhaust heat riser valve on the car. Never had a heating problem when I was driving it. Don't ask Steve how long ago that's been. It's embarrassing.
TomComment
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Re: Overheating 57 dual quads
Tom, it can't be embarrassing---we are still on the top side of the dirt and can remember those times smiling! It has been nearly 50 years, though.
I would not have bet I would have made it this long. (Age is only a physical thing---NOT a state of mind.) I gotta go now and look at her again, maybe caress the Bucrons, adjust the linkage and count the money in Nancy's coin jar to decide the next project. I am still planning on coming up but just don't know the dates yet. Nephew is getting married in Indianapolis August 31. Steve
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Re: Overheating 57 dual quads
For the last couple years.....I too had an overheating problem with my 270hp, Triple Crown '59. After driving the car just a few miles, the gauge would be pegged. I tried EVERTHING including carb setups, gasoline changes, replacing the waterpump, flow testing the coolant though the engine, installing an extra elecrtic fan to pull more air through the radiator, pulling the radiator and having a professional boil it out, using the "purple stuff" as a coolant, bought an portable heat gun to check engine temps, changed my sending unit out several times, and a whole host of little things. I solved the problem very simply by FINALLY going back and doing the one thing that I had been told to do early on....and I did not believe would help.....that is....check your initial timing. Read the last issue of the Restorer Magazine "Beating the Heat" by John Hinckley (and I won't go into detail) My timing was set at 2 degrees advance instead of the 12 degrees that it should have been (believe it or not). After changing this one variable....my gauge went from about 220 to about 180 degrees. Read the article.....do want John suggests.....I think you might be suprised!Comment
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Re: Overheating 57 dual quads
I have always ran every 283 derivative I had with an 097 cam at 10-14* and never had one that got hot. My '59 always ran lower than 180*. Even the '62 Impala convert with the 097 equipped 283/stick ran cool
TomComment
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