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dave 05-17-2010 07:53 PM

cross overs
 
installing cross overs on a stock 502, any advice on problems i will run into ?
Dave

Rookie 05-17-2010 10:18 PM

All or none of the above:
High water pressure
Fluctuating temperature during idle
Hot spots in the heads or block

Advice
Water pressure gage
Drill out the back of your intake to make sure proper flow through the head without circulating pump.
Put 2 3/16" holes in you thermostat
Get some thermotemp labels to put on the 4 corners of you heads to make sure they cooling properly.

ezstriper 05-18-2010 06:07 AM

I run one, have none of the above issues, do run the one with a bypass so you can run a thermostat or will run to cold, I did drill a couple of 1/8 holes in the thermostat, works fine...Rob

Rookie 05-18-2010 08:58 AM

I have 2 identical engines. I put crossovers on both. One is just fine and no problems. The other keeps taking out #8 exhaust valve and once #6 exhaust valve. I then took a laser pyrometer and let the engine idle and kept taking temp readings at the 4 corners of the head. The highest that the heads got on around bank #1 #2 and #7 was around 170* on bank #8 the head reached a temp of 255*. This was while idling with no load. I don't want to know how how it was getting under load and taking out the valves. :eek: I have since drilled out the back of the intake to promote flow from the back of the heads. The other engine is just fine and have had no problems.
These are the thermolabels I put on things I want to know how hot they might have got when I might have problems. You can put them on the back side of you oil filter, on your heads, oil pan. They show the highest that the label saw.

http://www.mv.com/ipusers/paperthermometer/


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