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I have a cool head I want to run on my quad and I need to know what dome to run so I won't have to run race gas. Any ideas on dome size so I can run pump gas?? Thanks
 

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I have a cool head I want to run on my quad and I need to know what dome to run so I won't have to run race gas. Any ideas on dome size so I can run pump gas?? Thanks
I would suggest a full UCCR first...look under the BDT Motorsports section on this Forum for step by step instructions. If you want to bypass a full UCCR (not recommended), you can error on the safe side with a larger CC volume than you will likely need.

For an OEM cylinder from 66MM to 69.50MM, a safe CoolHead Dome Volume for Pump Gas is 22CC...You will also need to check your squish clearance to confirm it is between .045" to .065". This will give you 155 lbs to 170 lbs of compression depending on the bore size (66MM or 69.50MM) and the condition of your cylinder bore & rings and final squish clearance.

Carlos
 

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I would suggest a full UCCR first...look under the BDT Motorsports section on this Forum for step by step instructions. If you want to bypass a full UCCR (not recommended), you can error on the safe side with a larger CC volume than you will likely need.

For an OEM cylinder from 66MM to 69.50MM, a safe CoolHead Dome Volume for Pump Gas is 22CC...You will also need to check your squish clearance to confirm it is between .045" to .065". This will give you 155 lbs to 170 lbs of compression depending on the bore size (66MM or 69.50MM) and the condition of your cylinder bore & rings and final squish clearance.

Carlos
Hello can you help me, on my trx 250r I only have a 20cc head to put top and I can only put 91 octane gas (width 69mm, 72mm travel) I don't know what to do
 
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