The Honda Dr.

What's up H-T??
Just got my p8r head back from the machine shop.. decked, new guides, seals, 3 angle cut.. etc. Planning on installing this head on my hi comp jdm b20b ( '00 has knock sensor) which has the PHK pistons. 9.6:1 CR. Been doing some research but can't really find a definitive answer.. This head is desirable because it has 33mm intake valves similar to a vtec engine, and flows better than the p75 head currently on there. Anyone had experience with this combo as far as P2V clearance/valve reliefs in the pistons or is it just bolt it on and go? Im assuming it should work fine being the p8r has an 84mm combustion chamber which matches that of the b20. I will also be adding in a set of crower 403/404 cams, ARP head studs, and supporting valve train down the road.. Any insight as far as pitfalls is greatly appreciated.. Just to recap b20b phk bottom end, p8r head. Thanks

spAdam

iTrader: (1)

Everything will clear, on stock cams. It gets a little to close for comfort with anything over that.

Remember the P8R also has larger combustion chambers (47cc) so that is going to lower static CR significantly. Compression is going to be a bit low for cams that big. As you start closing the intake valve later and later the dynamic compression is going to **** the bed.

Mock everything up and measure/map the P2V clearances (like for real, not with clay). Put the data into a spreadsheet and save it. That way down the road, when you want to cam it, you can just look at your spreadsheet and decide if the cams will clear or not with nothing more than the cam spec card. That's the best tip I can give you to avoid any future pitfalls.

96ekb20

befor you even think of upgrading your cams you need to upgrade your pistons. you dont have enough dynamic compression with stock phk pistons for those cams. btw 403 and brain crower stage 2 work with stock valve springs. your car will idle like total crap with after market cams with stock compression. btw if you add pistons ycp 84mm itr pistons or nippions 84mm itr pistons or 84mm p30 are fine but get the block decked .012-.015 so the pistons are almost flush with the deck and it will run very very well.

96ekb20

but too your question yes it will go on no issues. no need to check p2v its a head that came factory on that engine and with that head you will have 9.3:1 compression.

spAdam

iTrader: (1)

Your grammar and punctuation is so bad in your last two posts that I don't even know what you are trying to say.

P8R cams are not the biggest. They are in fact the opposite as far as I've seen

96ekb20

p8r cams have been shown to make 3-5 more whp over p75 cams

v4lu3s

except i dont think p8r cams are called crower 403 or crower 404.

The Honda Dr.

Thanks for the input everyone.. Good to know the valves will clear. So being that with the bigger chamber on this head will result in slightly lower compression, do you think I would benefit with going with the 402 cam instead?? I understand high compression + nice cam = good n\a motor, but I'm trying to make the best of this head before I go tearing into the bottom end. I figure bigger valves, better flowing head, a good IM (currently b18b), and a decent cam would give it a lil more kick then it has now. I already have an itr header, 2.5 catless catback, cold air, 12lb flywheel, and gsr trans as supporting mods. The benefit is minimal down time because its just a head swap. If I'm gonna tear into the block, I'd do the pistons, water and oil pump, rod bolts, and throw on the b16 head I have sitting in my shed. But its all good to know for whichever route I take..

blackeg

no offense here, but wtf?

p8r's come with that tiny *** intake cam and the same exhaust cam as p75's. the p75 intake cam is the biggest oem nonvtec cam and is actually a nice little upgrade in a p8r head.

The Honda Dr.

So would i be better off adding 403/404 cams to the p75 head or put the better flowing p8r on with a pair of 402s??

The Honda Dr.

Anyone???

spAdam

iTrader: (1)

I think 403 and up are going to be too big for your combo, but I don't know for sure. Let me see if I can dig up my cam spreadsheet later and run some numbers for you. It's just a reference as I'm not 100% confident on Crower's advertised numbers.

93egSLEEPER

I have little experience w/ B20 non-vtec, but IMO the 402's are a better choice. They will produce the most usable power band on the B20. You really want to focus on the mid range TQ, that is where you will find all your power and make the fastest car. The last 2-300RPM the bigger cams may give you will make your motor suffer down low. In this case, not a good trade off. If you were going to turn 9k then it would be a different story.

Just my .02. using my domestic knowledge on this one

blackeg

#singlecamprofileproblems


ideally you would use different pistons to bring the compression up. rsmachines or ycp itr knockoffs will do the trick. arp rod bolts in the oem rods and your good to go.

with a thinner hg and/or some milling to offset the larger combustion chamber id bet with cohesive bolt ons and a solid tune you can get 150/14X to the wheels on the p75 cams. possibly some 402's on top of that is about as far as you can/want to go on the stock block...

gearing will do wonders as well. gsr gears are a good all around combo, b16 gears are awesome for acceleration but that 5th gear blows on the highway. b16 1-4 and a gsr 5th is a fantastic combo

The Honda Dr.

I'm not gonna be revving this thing to the sky, just staying within the stock redline. I know the rod bolts are the weak point of this motor and I already have the p8r freshened up so it seems like the p8r with some 402s is the way to go. I know it has a 47cc chamber and as 96ekb20 said, itl slightly lower compression but should be in the ball park of 9.2 - .4
Hopefully this head with 402s and a nice IM (I'm thinking skunk 2) with a bigger tb should give it a lil more kick. Rite now I'm running an obd0 pr4 but have a chipped p28 with s300 I just have to convert to obd1

I hear ya there man.. I'm running as ys1 cable gsr tranny rite now and at 80 mph in 5th its like 4200 rpm... Lookin into an ls 5th

The Honda Dr.

Thanks dude.. The more info the better

spAdam

iTrader: (1)

I wouldn't. I can't wait for an opportunity to put my stock 5th back in. The LS fifth made the car a bit quieter. The mismatched drop takes a lot of fun out of the car though, and I miss having such a nice usable fifth around town.

PyroProblem

I kinda feel the same way sometimes. I have a jdm itr tranny with the 4.7 fd and the LS 5th gear. When your getting on it it's all good and hauls *** but when you go into 5th, the rpm drop really hurts acceleration. But it helps with hwy mpg which I do alot of so it's working for me.

blackeg

ls cable 5th gear is right between a gsr 5th and an ls hydro 5th.

F22Master

5th gear is all personal preference. If I could get a .6x 5th gear I would lol. But, I sometimes spend 4+ hours on the highway cruising at 80+... And I also have the motor to pull the car at that speed and low rpm.

If anyone is interested, I have a cable (YS1) 5th gear set I am looking to get rid of. 0.742 ratio. Will trade for LS hydro 0.714!

PyroProblem

Ahh. I did not know this. Thanks!