hi i have little Q and A for you guys. i em building or getting a shop to build my engine for my Turbo AWD 90-91 CRX i will be buying when i find the correct CRX (not junk that i've been seeing lately)
i will be going with a B16B block and rotating assymblely, i want a vtec head with most flow through it ill list them and i want to know witch head has the best stock flow and biggest intake port gasket.
B16a1
B16a2
B16B PCT STAMPED on head
B18C1
B18C5 PCT STAMPED on head
B18C5 P73 STAMPED on head

i will be heavily parting the head. but you can not change the port size at the intake gasket cause the way the head was built. boosted would blow thiner gasket.
and leak too.

 

All of the B16 variants are basically the same, except for the P73/PCT ones having a small amount of porting already done from the factory. B16/Type R heads should all be the same casting but there are iterations (PR3 vs PR3-2, etc). There may be a slight difference in the casting of the A1s as well, I don't remember and it's literally been decades since I've thought about it so I'll let someone else chime in if that's the case. ITR and CTR heads are exactly the same, all had the same exact part number, USDM and JDM. P72 heads (B18C1) have a different combustion chamber (quench pads) and a different entry angle on the intake ports is a bit steeper (so less of a turn to the valves) as I remember, but at the end of the day it's six and one half dozen when choosing between a P72 or PR3 casting.

Either way, if you are going to do a bunch of work on the head, there's no point in spending the extra money on a Type R head. It's much more valuable at this point to someone who is doing a stock resto and should probably be left as such. All of the parts and work that make it a Type R head will likely go in the bin for your build, so just start with the cleanest base head you can get your hands on.

 

how much ft tq do you think ill get with 1000hp? 45psi or 50 psi and kelford T2 cams in a B16B type R

 

i checked with my engine builder and we are doing a 90-91 CRX Turbo AWD B16B Civic Type R build. yay! its going be fun.