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High Compression Head
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Posted by: sldhd700

Has anyone heard when the the high compression head for the liquid 90 is going to be released from DRR. I m thinking about pulling my sons off and getting it milled. If the new heads are going to be out soon I ll wait.

Posted by: bulldogfallon

DRR head will not be out right away...

There is a lot more to it than just milling a head....If the squish isn't reworked you might not see the performance gain you are looking for...

It could also cause hot spots from where the squish meets the cylinder.....

The water cooled head would also need the grooves re-cut for the head seals.

Not much for the water cooled quads yet, but soon there will be lots to choose from (hopefully)

I know DRR has invested heavily in the water cooled direction.

Posted by: sldhd700

Thanks for your response Bull Dog. I was just hoping there was something happening soon with these heads. I guess I ll have to take our head over to our local shop and have them work it over for me. I m only getting 120lbs of compression out of this motor and would like to see about another 25 to 30. My son is chasing points in two series right now and I m scratching my head trying to come up with easy horsepower.

Oh yeah
I just want to say thanks for putting my sons pic on your trailer. He was way excited!! Could you send me a high resolution picture of your trailer with his picture? Just something to put in his scrap book. sldhd700@aol.com

Thanks
Shayden Housley #39

Posted by: bulldogfallon

No Problem...that is what I am here for....

I wonder if you could mill the cylinder (top or bottom a little)

Some have done this to the water cooled 70s to take advantage of better port timing and to bump the compression.

The 90 head you have can be made into a HC head...it is just not as easy as milling it though. (i am not an expert in this field so you may want to call one of the engine builders)

Posted by: QuadJunkies

Hetricks will have one as far as I know,if they dont already have it .I know when we was going to go with the WC they were expecting them to ship anytime.