superturboprelude

ok guys i used the zeal auto compression calculator http://www.zealautowerks.com/hfseries.html
and i put in f20b head and f22b-a1 block all stock internals and its came out to 11.00 compression is that rite or not please tell me what the comp will be with this set up im about to build on for turbo thanks in advanvce

94Vtecluder

No that doesn't sound right. Some of the numbers in that calculator are off. For instance it calculates a stock USDM compression of 9.89. Try this other calculator it seems to have better calculations.

http://www.bsperformance.com/compcalc/compcalc.htm

It calculates a stock USDM compression of 10.01 which obviously is closer to spec. In that calculator it says you would be around 8.40. The major difference between these 2 calculator seems to be in the measurements of the F20B head and specifically the CC volume. This one I just gave you says the F20B CC volume is 53.8 where as the one you listed gives a volume of 50.00 CC volume. This some what concerns me because 53.8 is the same volume of the H22 and the F20B is supposedly supposed to have a smaller combustion chamber. If you have the head maybe you can take some measurements.


Edit - Ya the CC volume of the F20B is ~53.8. With a 85 mm bore I guess the head really is cast different than a H22.


Modified by 94Vtecluder at 6:59 PM 6/13/2007

mgags7

...reason being the f20b head is nearly identical to the h22 head, which is 53.8cc

the f20b head on an f22b block should yeild lower compression than stock, bc of the extra 3.8cc of combustion chamber, the f22b head is 50cc like the h23 head.

next time do the math yourself, check the FAQ for a thread with all the measurements you need.

rogerdarnell054

Is the f20b head good for a h23a1 block