View Full Version : Portland National/Regional May 13/14

05-18-2006, 03:38 AM
Brian (50% owner) took our 86 Camaro A sedan to Portland for it's maiden vogage in the A sedan National waters, and we returned home to Vancouver BC very humbled.

There were all kinds of carburetor and some overheating problems. The whole wknd. just reinforced the old adage "NEVER TAKE AN UNTESTED RACE CAR TO THE TRACK!" There were only 3 National entries. It was all very frustrating.

Just curious, but what kind of oil cooler should we be using?

We hope to do better at the upcoming Seattle (Pacific Raceways) double National.

Robert Barg

Mark Allen
05-18-2006, 04:47 AM
The best kind of oil cooler is Mobil 1 and remove the gauge from your dash............ (ok just joking)

Be careful, if you have your air to oil cooler in front of the radiator on a Camaro you had better insure that the airflow through your front end is as efficient as possible. No leaks etc. Seal up everything top, sides, etc. Also look to see if you have the factory ducting from the nose to the radiator, that helps a ton. There are several factory plastic pieces that close out under the nose in front of the air dam, as well as the sides. If you don't have these either buy them or make them.

If you're still having trouble, get the oil cooler out from in front of the radiator. It doesn't need to be right in the air stream to be effective.

Additionally, what rpm are you running your engine to. Basically, if you're running a really competitive national car and spinning the engine to over 7k rpm you absolutely need a cooler. Some guys don't spin their engines over 6000 and if this is the case you can get away with Mobil 1 and no cooler. Try it at a track day and see what happens to your coolant temps.

As for your carb issues, that should be the least of your problems. The holley 4150's are darn near bullet proof if properly maintained. Most likely your fuel problem is somewhere else. If you're having carb problems there are a couple of things to check besides the basic float level etc. Do you have the bronze filters in the float bowls where the rail attaches? Take 'em out!

For other fueling problems start looking at your fuel pipe routing (is it picking up exhaust heat?) and your tank pickups (are you floating one in the corners).


05-18-2006, 08:19 AM
Mark makes many good points. The sealing of the area leading to the radiator is critical. I use thin aluminum and take care of the little holes with metal tape. I run an air/oil cooler that works well. It is in front of the radiator, but a little bit away to allow air to flow around it and into the radiator. I think the hot ,pun intended, set up is the oil/water cooler, whether within the radiator or as an add on. Everyone who uses those seems to be satisfied. I may be changing to that type in the off season.
Using Red Line Water Wetter and distilled water seemed to knock off a few degrees and be sure to have a high pressure rad. cap. I think mine is 21psi, as I recall. The real key is to make sure that every bit of air, that hits the intake, goes through the radiator, not somewhere else.
On the carb side of things. I had problems until I went with the road race floats. They stopped the fuel starvation on certain corners. Tuning the accelerator pump capacity, cam curve, etc. took a lot of testing until I got that stuff all right.

05-18-2006, 09:54 AM
A few extra thoughts:
1. A oil/water cooler will also bring oil temp up faster (a benne in the early CenDiv races)
2. Never underestimate the value of a good radiator and cap. And be sure to inspect your radiator for rubber and grass clogging. That'll make a difference.
3. F-cars get most (but not all) their air from underneath the front spoiler. Make sure that your lower air dam (the plastic one that attached to the radiator support) does its job and that the factory front spoiler isn't drooping (from rubbing or a tire wall meeting)
4. Get all the ducting closed up. It might look terrible, but use cardboard and duct tape in the short run until you can get your "fab" groove on and finish it up correctly.
5. If you aren't a carb guy, find someone who is. (I'm not, but will learn to be so that I don't leave it to tech to tell me something I didn't know about my car). But like Mark says, these Holleys will almost run right out of the box, albeit not up front.


05-18-2006, 02:20 PM
thanks guys, for your advice. We will certainly take heed and start work.

Robert Barg

05-19-2006, 01:12 PM
I am the driver of the car mentioned above. Here is some info the rest of you might find useful. We have an oil/water cooler in the car at this time and I will be removing it this weekend. I found a major drawback with this design is that when one temp goes up, so does the other one. This is what hapened to me and when I pitted, I did not know where to start looking for the problem (turns out our regular oil we had used for break-in was to thin). I will go back to a oil/air cooler and run Mobil 5/50 (best oil for your buck). Our carb problems are very funny, durring storage, when the float bowls were dry, a family of bugs moved in, yes bugs. When we pulled the float bowls off there were fifty or more little guys with legs in there. They had been pluging up the jets and making the car run like crap. Hopefully know that we have the bugs worked out (pun intended) the car will work a lot better.