You were worked up when filming this! Had me pumped to find out this is in my crx I just purchased. Did a valve adjustment to confirm a p8r head on p75 cams with a b20b jdm high compression bottom. No idea what is internal and may never know.. the fuel mileage is what I noticed compared to my stock b20 high compression.
If it has a knock sensor it’s 9.6:2 compression with the b20z pistons. If it doesn’t, it’s either originally equipped with a P8R (and has about 9.3:1 compression / don’t remember specifics, that may be off by .1) or is a b20b4 block with 9.2:1 compression pistons originally equipped with a p75 that’s been swapped to a p8r head - what does the block stamp say? (If it says b20b WITHOUT a number after it, it’s most likely a a JDM engine that came with the p8r equipped.) Unless you measured the can by itself, chances are it’s got the JDM cam, which is not great, and you should look for a set of USDM B18B or B20 cams.
@@gostickorgohome so I discovered later that the one I thought was a p8R head is just a high compression JDM B20B. Your info is correct I think too. I had an EG hatch with the same setup as my CRX except a b16 transmission to the GSR for the CRX. The CRX on the highway just felt so much better.. Same weight too but I suppose the aerodynamics of the REX came into play as well. Just sold the EG & keeping the Rex. I have two VTEC heads and will build a B20V someday.. I do like the high compression over the low for stock, that extra couple 100 for the RPM's is peace of mind with a short transmission.
JDM B20b w/P8R head makes 143hp 132 ft/lbs TQ 9.2:1 compression. JDM B20b w/P75 head makes 148hp 136 ft/lbs TQ 9.6:1 compression. 99'-01' CRV.. When it was time to replace my broken B20z the choice was obvious.
P8R's (and vtec killers on a p28) have always been the secret weapon of fixed cam tuners. Never caught on because they were difficult to import. You seemed to be rolling the dice. Also, the 99-01 b20z cams are a touch hotter (think just the intake cam) than the usdm b20b. People like the b20vtec because it bumps compression with no head work, but at this point all b-series need head work.
Great info. i alwase wanted to get a p8r head and put it on my 700 whp b18b. p75 head port matched with yes you guessed it Crower 404's.lol i want to also see what crower 405's will do they have higher lift than the 404. i have some interesting dyno graphs on the diffrent cams i went through on my channel you may want to check it out.
So the original B20 by Honda came out in the second gen jdm Honda Prelude SI leave it was 85 to 87 which is known as the b20a gold top and that's what this head is based off of
If you’re engine is not a Japanese’s domestic market engine (and only specific cars at that) that you are correct it’s a P75. You can also look at the code stamped on the side of the head, it will tell you.
@@b20eg195 the compressions are stated in the video. He’s talking about the piston codes. The P8R apparently has its own piston, which is how Honda got 9.2:1 compression.
So I have a crv with ofc a b20z2 and p75 head, I just purchased a p8r head since I have to replace the head gasket here soon and might as well go with a little upgrades, I plan on port matching everything polishing and sending it to get machined. So with b20z2 and P8R it should have more compression and make more power than a full P8R long block? You mentioned the intake with the volume box is the best flowing it being stock, I have a skunk 2 intake that’s ported, do you think porting the volume box Intake or just throwing on the skunk 2. Not sure if I made sense but I tried lol
Your c/r should be the same as a normal b20 p8r at 9.2:1 i believe. Using your b20z2 cams in the p8r should increase hp over a stock p8r b20. A non ported intake manifold would likely be best to use unless u have an aftermarket cam. Reason being the ported manifold should bump the powerband up but your stock cam doesnt make good power in the higher rpm range.
@@timm5970 it'll be about 9.3:1 - the P8R B20 couldn't have come with low comp pistons, and if you do the math (using high comp pistons and the larger cc chamber), it drops compression from 9.67:1 to about 9.37:1
short answer - the skunk2 is *probably* better. Long answer: the box intake is the best stock manifold, yes. the box eliminates a deadzone between 3500-4500 rpm and still beathes at higher. (side note - that deadzone applies to stock B18B1 P75 intake manifolds, the CR-V "giraffe manifold is trash and I'm not even including it in this) there was a thread i saw years ago where a guy had a P8R B20 in his DA integra, and it had a flat torque curve and a VTEC-like power climb - it was glorious. He used the box manifold for it. thing made solid power. HOWEVER - the skunk2 manifold is most likely better for you because (and I don't have data to back this up, but I have some experience and related knowledge) - the SKunk2 intake manifold almost certainly breathes better than a stock P75 intake, which means it almost certainly breathes better than the box as well. you can always swap and compare power results. it's an added few steps and expense, but I like having answers, so it's what I would do
GoStickorGoHome yeah for now I’m gonna clean the ports on the stock intake and port back it to my new 68mm throttle body. I’m hoping to have close to vtec power but non vtec, I’d be happy with 170 but if I make more I think people who don’t wanna go through the haste of going vtec should definitely go p8r. I will be posting the build on this channel hopefully close to the end of the month.
So badguys worldwide said they used a “low comp b20” which would imply p3f pistons but im sure they are phk which makes the compression ratio 9.2:1 i believe. The cc of the bowl is greater then the p75 head which cause the drop in compression ratio. The cams used were regrinds and they were rocket motorsports stage 4. My goal is to source a p8r, use crower 404s, and ycp type r 84mm pistons. Just cant find a freaking p8r head without buying a full engine. I already retrofitted a b16 intake manifold to the pr4 head and i habe 70mm throttlebody that i need to match up. Slowly but surely getting it done
Like i said in the reply to the other comment, i'm pretty sure that "9.2:1 compression" number is actually wrong. because (and i said this in the video), there is NO WAY to get higher compression (at all) starting with the 8.8:1 Compression pistons. So a P8R equipped B20 has to have (by process of elimination) PHK, 9.6:1 pistons. - I don't know personally, but when badguys said "low comp" that can mean 2 things - either they put a P8R head on an 8.8:1 block, OR "low comp" meaning the "9.2:1 compression" number (which, again, is more like 9.3 or 9.4:1).
also, best of luck with the build man! that'll be a solid build, and i'd recommend getting a basic port done if you want the most out of it. *thumbs up*
@@gostickorgohome Im sure the p8r is only using phk pistons. With the added cc it drops what would normally be a 9.67:1 c/r down to a 9.2:1. If it was p3f pistons it would drop the normal 8.8:1 c/r down to something ridiculously low like 8.4:1 c/r. Pretty sure all p8r b20 use phk pistons but call the "low comp" not in reference to the pistons but to the actual c/r compared to other b20s with 9.67:1 c/r
@@timm5970 I believe all jdm and usdm b20b motors used p3f pistons. It's the larger combustion chambers of the p8r head combined with p3f pistons that create the 8.8 motor. Use of phk pistons as found in the b20z and late jdm b20b should bring you to 9.2 though.
@@beezowdoodoozoppitybopbopb9488 incorrect. First off the b20b is only a jdm engine. USDM engines end in a number like b18b1. The b20b from japan use both PHK and P3F pistons(ive even had one with phks).
I found a p8r head locally and will be installing onto b20z2 with 9.6 compression what would be the best way to keep the 9.6 compression while installing the p8r head if used with a stock 3 layer headgasket?
What's the bare minimum you'd do (cost-wise) to bring out the P8R's true potential on a JDM B20B low compression block? I do plan to turbo it. Right now my shopping list is a turbo kit, rod bolts, head studs and maybe a super tech head gasket. Planning to stay under 300hp. Thanks man!
@gostickorgohome2496 Yes. Anything the machine shop could do to get the most out of the head. Such as gasketmatching the ports. I want to run the OEM valves. I'm putting fresh valve seals, head gasket, head studs, etc. I'm just a noob to the idea of machining and need some ideas to take advantage of the P8R platform and its air flow strengths Would it be overkill to do any porting if I'm just going to turbocharge it?
In the video I do mention that the P8R uses the same cams as the P75. You can use aftermarket exhaust valves if you want, but intake has to remain stock (unless you want to pay the crazy price for custom). Port work would be cleaning up the casting, some smoothing out of the bowl/section right above the valve seat, and don’t “gasket” match - you want to match the intake manifold and port to each other, the gasket is going to be a much larger hole, and no gasket is the same. So match the port and intake to each other, and don’t over do it. *too* much flow will murder port velocity, and that’ll actually lose you power. Cleaning up the casting, blending the area above the valve seat, and matching the manifold and port are what I’d go for. As far as cams, if you’re doing a turbo setup, stock cams will work just fine for now. You’ll want to be conservative with the ignition timing as spikes in cylinder pressure are what crack the B20’s weak cylinder walls. But my friend ran over 450whp without issue, just had a conservative tune with the ignition timing.
@gostickorgohome2496 Thanks for the response. For some reason I misheard you and thought you said the P75 cams were .020" higher in lift. It's no matter though! I plan on running a 195lph relayed fuel pump, 750cc Bosch injectors, on hondata S300. I was told that would help avoid catastrophic detonation and wrecking the sleeves. Definitely going to stay under 10psi. Hopefully, somebody around here is competent and knows how to tune a b20 carefully enough I know nothing of tuning. Especially not with something as concerning as a b20. Do you have any other advice for me regarding that?
That's a really interesting thought process on p8r from factory. I have a p8r swap, I will have to see what pistons are in it when I do the head gasket... I think the best oem b20 setup is hi compression block, p8r head, b20z cams, b18b intake manifold, ITR throttle body. The reason this rarely happens is if you have the skill to install cams, once the oem b20 ones are out they never go back in. Seeing that one build you talked of with the 192whp and stock compression gives me hope. I'm going to be using regrinded cams in mine...If I could break 145 whp I would be happy
The only change is make is using the B20Z manifold instead of B18B- the P75 intake manifold creates a torque dead zone from 3500-4500 rpm, and the resonator box on top of the b20z manifold fixes that while still flowing the same up top. And according to another comment the P8R may have its own pistons, labeled similarly to the low comp, but with additional letters.
@@gostickorgohome so I'm using p75 integra intake mani on p75 headed b20z...I don't disagree about it being "torque less" around 3500 but it pulls harder than the b20z intake manifold for sure (in an RD1.) those numbers of p8r vs built vs p75 head are good man...I wonder if a stock p8r with cams and valve springs will give a b16 a run... I'll be using delta 402.5s...supposedly they play nice with OEM ecu and will turn all the way to 8k... The stock p8r cams are definitely the worst...mine are DEAD after 6200, it literally feels like the car is slowing down if I take the obd0 computer to the limiter (which is 7k on obd0 integra ecu)...I can't wait to do cams My p8r has sk2 intake manifold and blended size to TB...I think OEM cams match best with p75 obd2 but I'll do those cams soon...maybe I'll get gsr type hp!!!
@@KP-to1mk that’ll be a good setup for sure More usable power across the rev range, and with cams I could see GSR power for sure, but probably also more torque - but definitely if you get a basic port blend to clean up the core shift P8R heads have
sorry im late to the post. if i want to put ferrea valves and better springs/retainers what would i order under? or look up? i have to apologize ive always built lsvtecs etc. but have a friend wanting an all motor b20 build for race season. def looking up the 404 cams or something nasty from rocket. if anyone has any suggestions tried and true, to get over the 200whp mark please message me or tag me. id prefer someone that has actually done it :)
Sorry I’ve been busy with the day job for awhile. The only 2 options for the P8R for intake valves are stock or custom valves (I think Ferrea can do special order to specs, maybe comp, can’t quite remember). Exhaust valves are the same as a non vtec b series. Valve springs are the same as non vtec, and retainers as well. So whatever aftermarket springs and retainers for non vtec work for it.
My motor is apart it's a built non v b18b... I'm thinkin about putting my cams and springs in my p8r head and using it... but idk if I'll have performance or head gakset issues being turbo. Since the 81mm block and the 84mm head . The cylinders would he hangin out making a lip in the cylinder I think ?
You don’t want to put an 84mm combustion chamber on an 81mm bore cylinder. You are correct, that would have overhang. There’s a few reasons why it’s not a good idea. If it were me, I wouldn’t chance it unless I had something else to drive as a backup. Not sure about the valve clearances, as they seem to come pretty close to the edge of the chamber.
I have a P8R head, and I am sending my block to get sleeved/assembled with Iron sleeves, forged pistons/rods, should I do a mild build with P8r or just go vtec?
Depends on what you’re trying to make, power wise. My friend used a P8R head on a turbo 2.0L build with wet sleeves, and it made 625+ with a log manifold and some cams. NA you’ll make much better power if you get head work done, as I’ve said in the video these usually some significant casting overhang in the ports, but it’s easy to clean up with a basic port and polish/bowl blend.
@@gostickorgohome I want 600whp reliably, I have a PLM topmount, edelbrock victorx, 10.5:1 forged pistons, forged rods, assembled by JBRE in tampa with sleeves at 84mm. I have stock head for now. Going boost by gear, comp twin disc, and did I mention its my daily? :)
@@flcivic7545 i know that’ll work because my friend was something like 11.5:1 CR, crap cast log manifold, and an HX35 (I think?) Holset diesel turbo, and it revved to 8800 and was still climbing at the limiter making 625whp and 450wtq. Stock P8R head casting with aftermarket exhaust valves (no one makes intake valves for it, but the stock ones are strong enough), and upgraded springs with rocket cams.
Mine is a b20b came from a 1997-2000 model CRV is it a 8:5:1 compression? Can I change my pistons to a YCP highcomp piston 84mm to increase its compression? What do you think about the YCP brand piston?
What makes it seem like it wouldn’t? Yes, the P8R fits onto any B series engine with a cylinder bore of 84mm or larger (assuming the head gasket matches). So any B20 can have one on it.
@@gostickorgohome I was hearing in certain places that the low compression 8.8 ratio pistons valve reliefs might not be cut deep enough to fit the p8r 33mm valve size
I have a p8r on my b20b and you can feel the power loss at high rpm anybody know anything local tuners near ohio? Right now I have 207 whp 182 torque lmk
What exactly did u do? I didn't think u need to port the head to reach your goal? U should be able to rev higher if u had valve springs and some ARP rods bolts. I wouldn't call that lagging 207/182tq. I'm assuming that tq comes from the p8r head and idk what else u done. I'm sitting at 193/151tq. This is on a fully ported p75 head though. I need more compression or a p8r head to hit 200+. Every car and setup react differently on tune.
You can't unless you get custom valves made. My friend Ben used stock valves with 33psi and 625whp and has zero issues revving to 8800rpm. The stock valves are fine if they're healthy.
