Thread: Camaro heat issues & vac question

Tweet

I have a ’69 Camaro with a fairly new 350 crate engine. The engine is the 290hp GM product. The intake is an Edlebrock Performer with a Performer 600 (1406) carb that replaced a Holly 4010 600cfm. The exhaust is a pair of headers, not coated or wrapped. Ignition is handled by a Mallory Unilite/ vac. advance with a Hyfire spark box. Inital timing is at 8 degrees, 34 all in. Most everything else in the engine compartment is stock, water pump, radiator, shroud, fuel pump and pulleys. The fan is a flex, but it is one of the heavy duty ones, with large blades.

It has always run a little warm, especially during these Texas summers. Since installing this new, stouter engine, my water temp will not stay below 190 on the freeway unless the ambient temp is just above freezing. It'll hit 210 easy during last summer. I will be replacing the radiator with an aluminum one in the next few days. Probably with a inexpensive Jeg’s branded one. The one I have now has some corrosion. I’m sure the bright idea of lightly spraying the radiator with some semi-gloss black when I was re-doing the engine compartment to make it look nice was really a pretty stupid idea.

I had to drive way out to a job site last week, and when I finally got there my car would barely run. It died several times while trying to find the construction site. I tracked down some of the problems to vapor lock and a bad coil. To confirm my suspicions, I let the engine get really hot and when it started running rough I noticed bubbles coming into the clear filter I have. When I would spray the fuel pump and lines down with a garden hose, the filter would fill up and it would run a bit better. It would still run rough, and then it died a couple times. I had a feeling the coil was getting too hot. When I pulled the POS Accell coil off the oil in it gurgled. I swapped it out with an old Mallory coil. It would vapor lock but it didn’t die, and it ran smoother.

My questions are; do ya’ll think just a better radiator will stop the fuel from boiling? Or will the engine compartment be even hotter from more heat dissipated from the radiator? Am I problably going to have to take other measures?
(The fuel line, pump, and header proximity is pictured below)

I also have a question about vaccum too. I had been trying to tune my old worn out Holley two-piece and I finally gave up on it. I wish I would have replaced it years ago. When went do the idle mixture adjustments I noticed my vaccum readings were really low, like around 6-7 at 600RPM. I’m located about 600ft above sea level. The duration on the cam is 222/222. I was hooking up a T-adaptor in the vac line from the manifold port on the carb and dist. Last night, when I went to confirm these readings, I didn’t use the T and just hooked it straight. I was getting a reading of 12-13 at 600RPM and about 15 at 1000RPM (then vapor lock set in and I couldn’t get a good reading). I found that the dist advance module was leaking. I don’t think that is supposed to be happening. From what I’ve been reading, these numbers seem a little low too. Am I correct?

Sorry about the length, but I think more info is better then not enough.

"I noticed bubbles coming into the clear filter" that happens on all cars, thats not vaper lock or gas boiling. gas boils at 240 degrees, so unless your gas line is laying on the headers i doubt it. wrap some tin foil around the line and see if it stops.

I'm pretty sure the gas is reaching it's boiling point. I don't know if it is happening in the line or at the fuel pump though, but I literally watched it starve. When the car has to idle for extended periods it'll start surging. On occaision it will die too. I really try to avoid having to drive in heavy traffic on hot days.

Hopefully, that will be a thing of the past. I just placed an order for an aluminum radiator, catch can (in case it does spit up again), and a pair of Dynamax Cyclone ceramic coated headers. That should make for some easier Texas summer driving.

it might be but, what you see in the filter sounds normal. put tin foil or cloths pins on the fiel line should stop it so at least you will know.

I'm not talking about just a couple of bubbles. It'll start out that way then it will end up doing this when it gets really hot. The filter is normally totally full.

I took this video clip after my drive home today.
Windows Media video clip of filter
The water temp was about 192 degrees.

sitting there idling I got a feeling that's normal. I don't see boiling, I see normal bubbles. it don't take but a little fuel to make it idle. the filter is not gonna stay full all of the time, it can't. if its boiling you can stop it with some tin foil, wrap the fuel line and see. I,ve run cars 230 degrees, a lot of times and the fuel didn't boil. I' ve had the fuel to boil with the motor cooler than that, but I always found a reason, line to close to the header or laying on the block. a new rad. may fix your heating problem, but I don't think its gonna fix your running problem. nice pic.

I have a filter similar to the one you are running and it appears to me that yours might be installed backwards.

Originally posted by NTFDAY
I have a filter similar to the one you are running and it appears to me that yours might be installed backwards.

Nope, it's in there correctly. I had to go and check to be sure.

The chrome ends are labeled in and out. The out end has a recess to recieve the filter insert. I also located the instruction sheet for the Purolator replacement filters just to make sure I didn't have the spindle in backwards too.