For you LT 500's with coolhead owners:

What size dome are you running?
What is your compression?
What octane gas are you running?
What is your approximate elevation?
What size piston are you running (overbore, etc)?

Thanks!

 

47cc dome (Yes, custom cut) I'm not impressed by the offerings from cool-head... it's really not a "one size fits all" thing we're looking at here. I ordered a blank, and had it CNC machined to the specs I wanted (Narrower squish band/ diff. squish angle, smaller chamber, O-ring, etc.

~190 psi w/ snap-on gauge

110 Octane Unocal 76 w/ Amsoil Series 2000

Approx elevation ranges from 5K to 9K feet above sea level

.040 overbore

Here's a few questions to ask yourself... Is it an '87? If so, stop messin' around with head gaskets and go with Viton O-Rings... With higher comp... sometimes there's a problem with the head studs holding torque (Especially at lower elevations), replace the stockers with the newer shoulder style studs (10mm to 8mm stud)

What's been done to the ports? Nothing? well, you are probably fine with a dome that prodesign offers. If the exhaust port has been raised, it will directly effect the trapped volume, and directly effect the amount of compression you will end up with.

The amount of compression alone doesn't dictate whether or not you need high octane fuels, also the squish velocity needs to be considered. Race fuel only helps curb detonation... nothing more. Running race fuel in a stock engine is basically throwing $$ down the drain..

Do your homework, and you'll be very happy with the results.
Good luck!

 

Thanks for your comments. They were helpful, and well stated.

 

52 cc 215psi snap-on gauge C-12, 190 deg. ex duration, stock head gasket, .080"/2mm over, sea level to 1000 ft.