B20/b16 Hybrid "piston To Head Gap"?

We may earn a small commission from affiliate links and paid advertisements. Terms

Status
Not open for further replies.
J

JLG

Junior Member
First time in forum, long time member...

Just got through blowing my GSR powered Civic, car missed 2nd, valves floated, piston shattered, cylinder walls busted, head is cracked, and I'm pissed off!

I want to get back on my feet ASAP, so last week I got the B20Z2 (1999 CRV) bottom end, and am ready to mate it with a B16B head (JDM Type-R), whih I really regret when I found out how little of a difference there is in the A1 and B head, and a LARGE difference in the price. I need for someone very knowledgeable and preferably with past experience to inform me about something. I need to know how much I can shave/mill the head and still have enough clearance for the valves to open without the pistons slamming into them.

I hope the B20 bottom end turns out to be a better application than the B18C1 once I tranfer all the bolt-ons and internals, thank god I wont have to wind her out to 9400 RPM's when I shift, and I hope the new clutch I bought won't slip and cause the same problems missing gears the last time. :unsure:

I really appreciate the help!

OKAY OKAY it wasn't the clutch's fault, just dont rub it in my face
 
i hope this helps....

i do not exactly know how much is the clearance but from a bad experience doing the b20b/b16a build, the valves hit the stock pistons when i used crower 63403 at 3 degrees advance. i even enlarged the valve pockets.

so i think the clearance is not that good. clay the assembly before even attempting to start the engine......

gud luck
 
using stock pistons and rods from my b20z2 crvtec build-up I found that 2x is the most I could resurface the head without valve interference problems, I "had" the type r head, it has since been removed from my car :ph34r: (damn thief)

The type-r heads are very expensive, and if you mill them too much the valves come down and smack the pistons.
I could see where one of the valves came down and touched the carbon crud in one of my valve reliefs.
I was thinking about having my friend get me a 3mm headgasket from japan when he goes next week.
This should lower my compression to 170-185psi (I am at 205psi per cylinder) and give extra valve clearance, oh if you're thinking you can rev the stock bottom, with stock internals past 7000, think again, it will blow up when you get much past 8k, just ask cal.

To do it right you will need a bunch of stuff you don't have in stock form.
Just make sure the head, ecu and dist match, and do the PCV right or idle/power problems will occur.

good luck. (I hope u got money cuz it aint cheap)
 
Thanks for the help man, but one thing this redneck can't understand, what does 2x stand for, please understand Im not down with the lingo, Im thinking it's 2 mm (.064), but I want to check before I cut the head that much.

So whats up with Cal, he actually blew his when he went past 8K???? I don't get it, the rod lengths are identical (not considering the beefier stroke from the Crank), the rod geomatry is nearly identical, so why would there be a 2000 RPM difference between the GSR stock internals and the CRV stock internals. The VTEC accesories on the old GSR motor that turned out undamaged will be replaced onto the B20, including the water pump, underdrive pulley gear, the main girdle found on the VTEC B motors, and the cylinder brace that closes the deck between the cylidners.

Keep in mind the GSR's head was BUILT and every electronic, bolt-on, and headwork was made for High RPM performance, and all this technology will be translated onto the CRV-tec. It's really too bad I can't salvage the Intake manifold and throttle body from the B18C1. I don't even know if the header will bolt up the same as from the GSR! Well, hopefully I can get some more help on this, and please, don't be afraid to bash me for being such an arrogant jackass toward Cal about his B20, hopefully Cal will share some of his experience wit me, and bashing him will wake him up and tell this hick whats hapnin.

Well it's off to work on the B20 tommorow, so far the head is prepped and ready to go on the head with Gude 305P cams, and the new valvetrain. By the way, the GSR was all motor, and so the B20 will be all motor, that's the way it shuld be if you want the serious competition! Well, I got some more studying to do b4 skewl tommorow, Ill check the poss tommorow morning b4 I get bizzy wit da B-izzy (the scary thing is I'm a white hillbilly saying that, look out, I'm the Appalacians most wanted). Take it eazy for rizzy my nizzy
 
no no, 2x = two times sending it to the shop to have the head machined.
As for the exact RPM, cal said it was a shift from 4th into 3rd instead of 5th, when racing a vette, (hiss, white smoke)
But he's gonna build it up stronger next time.
He posted the story under kills, but I don't know if the posting is still up,
I think he listed what RPM he went to.
I know that with a block-guard and stock internals I could shift at 7k, before my head came up missing.
You should post pics on the build after you get it done. :)
 
what u need to do is. go to JE and get the pistons made for the B20 with the B16 head then u should have a better clearance for the valves and be able to retard or advance more
 
Originally posted by thetoymaker@Apr 27 2003, 03:56 PM
if you're thinking you can rev the stock bottom, with stock internals past 7000, think again, it will blow up when you get much past 8k, just ask cal.
Click to expand...

Wrong question to ask me, since high revs weren't what caused the engine to blow... I took that engine to 8500-9000 all the time, and it was fine, as long as I revved it smoothly (with gas pedal, not transmission forcing it to 9000+ from 5000).
 
Well, my GSR head is milled .030 in. It is my daiy driver and I have have no problems with it. The block is a 98 B20 with all stock internals. I am running CTR cams in it with a b16 tranny. Like I said, It's my daily driver. I travel all over Cali with it and actually, I just drove 2000 miles to Texas. So far, no problems with it. The piston-to-valve clearance problems occur when you run bigger cams than that. I rev it up to 8200 RPM and haven't had any problems either. If you plan on running cams bigger than CTR size, you should get those JE pistons designed for the head you use, be it a GSR or B16. You'll be glad you did. The problem with valve float happens because the B16/GSR valves are WIDER than the LS ones. You need to widen the valve recess on the stock piston, not make it deeper. Anyhow, hope I helped. Peace.
 
Say what???
you're using the civic type-r cams and you say you've got clearance?
I think not.
The cam lobes are too big and the valve relief clearance on the pistons is for shit.
Are you sure......?
 
Yes, I'm sure. I used the 94-97 VTEC Del Sol engine harness and the P30 ECU. I've built a few of these motors and reliability isn't a problem when you have the dowel pin holes redrilled correctly on the head. If you wanna be safe, just get the pistons. Stock LS/B20 rods can handle up to 9K RPM. But like I said, I've done a few with no problem using the ITR and CTR cams.
 
Originally posted by thetoymaker@May 2 2003, 03:16 AM
Say what???
you're using the civic type-r cams and you say you've got clearance?
I think not.
The cam lobes are too big and the valve relief clearance on the pistons is for shit.
Are you sure......?
Click to expand...

look, not to bogart the thread, but i've read a lot of posts that this dude has thrown his .0005 cents in and just about every time he gets shot down by someone who actually knows what the hell they are talking about. I come here for advice and i think that people who obviously aren't qualified should read more posts and pull head out of ass. Thank you continue thread.
 
thanks,
but I need to know, so I asked.

I will continue to ask that people who are not clear about their questions and answers to explain it further if it's something that interests me.
 
Status
Not open for further replies.

Similar threads

tboneair
Will i be okay to run my D16z6 head on a z6 block with Pg6B pistons
Replies
3
Views
2K
E_SolSi
E_SolSi
Ty95EG
b18b1 on stock p28 ecu
Replies
2
Views
2K
dilbeckskate
dilbeckskate
P
95 Prelude Swap H22A1 to H23A. HELP PLEASE
Replies
8
Views
4K
PreludeProject95
P
invisibledemon
A different kind of rebuild thread - espresso machine
Replies
13
Views
4K
ish
ish
T
Going turbo need help?
Replies
1
Views
3K
Briansol
Briansol
Back
Top