88-91 CRX D16A6 Cylinder Head CC

[bbreon]

After decking the head to increase the compression ratio by .5:1, what CC/cylinder chamber should be expected on the D16A6 head. How much did you deck to get there?

[B90278]

Originally posted by bbreon@Dec 17 2005, 02:26 AM
After decking the head to increase the compression ratio by .5:1, what CC/cylinder chamber should be expected on the D16A6 head. How much did you deck to get there?

68540



It depends on what else you did valve job, cut seats, surfaced valves, or replaced valves.

this is a good calculator put in your #s

http://www.knology.net/~jediklc/D.htm

[bbreon]

Originally posted by B90278@Dec 17 2005, 01:58 PM
It depends on what else you did valve job, cut seats, surfaced valves, or replaced valves.


this is a good calculator put in your #s

http://www.knology.net/~jediklc/D.htm

68596


All stock, had the seats cut twice now. Can't imagine that makes that much difference though.


I've seen this. Does it appear to be pretty accurate? I'm questioning its accuracy.

[Tom Blaney]

Originally posted by bbreon@Dec 17 2005, 02:43 PM
All stock, had the seats cut twice now. Can't imagine that makes that much difference though.
I've seen this. Does it appear to be pretty accurate? I'm questioning its accuracy.

68597



Every little bit helps, in motor prep it's all about the little things..

[bbreon]

Thanks Tom, but really, if the block and pistons are stock, there is a minimum cc that the head can have in order to be on the 9.6:1 max ratio.

Come on Tom, you build motors. You've had to cc the head chamber of a 9.6:1 compression head. What is that cc? Unless you also deck the block in which case you would take less off the head with more cc in the chamber.

Either way, care to share any details?

[Tom Blaney]

Originally posted by bbreon@Dec 19 2005, 09:56 PM
Thanks Tom, but really, if the block and pistons are stock, there is a minimum cc that the head can have in order to be on the 9.6:1 max ratio.

Come on Tom, you build motors. You've had to cc the head chamber of a 9.6:1 compression head. What is that cc? Unless you also deck the block in which case you would take less off the head with more cc in the chamber.

Either way, care to share any details?

68730


Not unless your willing to write a check, it wouldn't be fair to all the guys who currently run my motors to give away a trade secret.

Oh by the way I'm taking orders for new engine builds for the start of next season, I will be building a limited number of motors and it will be on a first come basis. As you can see by the lap time improvements of my clients, it is well worth the cost.

And then just think you will know the answer to the above question then too...
:smilie_pokal:

[bbreon]

Originally posted by Tom Blaney@Dec 20 2005, 03:57 PM
Not unless your willing to write a check, it wouldn't be fair to all the guys who currently run my motors to give away a trade secret.

Oh by the way I'm taking orders for new engine builds for the start of next season, I will be building a limited number of motors and it will be on a first come basis. As you can see by the lap time improvements of my clients, it is well worth the cost.

And then just think you will know the answer to the above question then too...
:smilie_pokal:

68802


Thanks Tom, I can respect that. How about this, does the link above to the compression ratio calculator, in your experience, appear to be accurate? You don't need to share any trade secrets to answer that do you?

[Tom Blaney]

Originally posted by bbreon@Dec 20 2005, 04:19 PM
Thanks Tom, I can respect that. How about this, does the link above to the compression ratio calculator, in your experience, appear to be accurate? You don't need to share any trade secrets to answer that do you?

68809


The only way to get an accurate reading is to do the burette and glass plate routine. Or if you have access to a "GOOD" machine shop, for a few bucks and some patience they can do it for you (which will be cheaper and more accurate in the long run if you don't already own the burette etc..)

Keep in mind that stock does not mean that it will meet the factory specs, although I have great respect for Honda consistancy, they still drink rice wine and saki .....

The web calculator will give you a number, but unless you can supply exactly what your head volume is. it will always be wrong. (Valve sink, casting flaws, etc)

Hope that helps