14-1 piston with rw race head?
#11
14-1 piston with rw race head?
Originally posted by: Dynoray
Any good engine builder will have a piston vise for their milling machine and can machine a 4 valve relief (two plane) piston in under 15 min.
So it shouldn't cost more then $20-$40.
Dynoray
Any good engine builder will have a piston vise for their milling machine and can machine a 4 valve relief (two plane) piston in under 15 min.
So it shouldn't cost more then $20-$40.
Dynoray
#12
#13
14-1 piston with rw race head?
I would think the amount of compression lost when milling a piston for valve clearances would be minimal. The only for sure way to check the compression ratio would be to CC the head, measure deck height, and enter all the info into a Engine Size/Compression ratio calculator. You can find these java programs for free on the web.
#14
14-1 piston with rw race head?
Compression loss depends, like you said how much material you remove and how much compressed volume you have for example:
on a 650cc engine with a 60cc compressed vol =11.83:1 C/R
If you have to deepen all four valve reliefs 0.5mm and the V/R's have 36mm radius and 18mm width (symetrical) you would lose about 0.508cc.
This would give a C/R (based on the above volumes) of 11.742:1
Oregon is right, you would have to assemble the top end (with clay in the valve reliefs) roll through one valve cycle, with the cams degreed in then remove the head and measure the valve to piston clearance to know how much to remove.
Dynoray
on a 650cc engine with a 60cc compressed vol =11.83:1 C/R
If you have to deepen all four valve reliefs 0.5mm and the V/R's have 36mm radius and 18mm width (symetrical) you would lose about 0.508cc.
This would give a C/R (based on the above volumes) of 11.742:1
Oregon is right, you would have to assemble the top end (with clay in the valve reliefs) roll through one valve cycle, with the cams degreed in then remove the head and measure the valve to piston clearance to know how much to remove.
Dynoray
#17
14-1 piston with rw race head?
killer thread, great info.
I asked MrHP a while back if I could use his 14:1 piston with my a1/a2 cams if I stuck an extra base gasket on, knowing this would drop compression slightly but just curious...
His reply was that I should be able to use the 14:1 no problem with the a1/a2 cams, no need for an extra base gasket, but that he does recommend a clay test to be sure first.
Oregon, have you tested this combo, and know for certain?
I asked MrHP a while back if I could use his 14:1 piston with my a1/a2 cams if I stuck an extra base gasket on, knowing this would drop compression slightly but just curious...
His reply was that I should be able to use the 14:1 no problem with the a1/a2 cams, no need for an extra base gasket, but that he does recommend a clay test to be sure first.
Oregon, have you tested this combo, and know for certain?
Thread
Thread Starter
Forum
Replies
Last Post
Logan Collins
Classifieds, Garage Sale & Swap Shop
0
09-05-2015 08:03 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)