stallinrawlings

well i posted on here this morning and spent like 30 minutes typing this up...
guess it's round 2 cause that didn't even go up...

What I have:
b20Z2 from a 2001 crv
P8r head milled .010" off
new valve springs and retainers etc
B18B1 Cams

Some things to know:
stock the b20z2 has 9.6:1 compression
it uses a p75 head - same as the b18b
the p75 head has a combustion chamber size of

stallinrawlings

this is ridiculous - then my computer froze in the middle of that the second time - i'll finish this later (-_-) so pissed

DA-NINE

Sounds a little like my build, I have a p8r with .015 off, Rocket Cams and valve train, on a b20b

https://honda-tech.com/forums/all-motor-naturally-aspirated-44/port-velocity-discussion-itb-sizing-3197806/


your compression will drop since the p8r has a 48cc chamber while the Pr4 and p75 have 45cc chambers.

Im going with RS or YCP ITR style pistons to bump my compression back up and pick up some wiggle room for a possible larger cam later on. the stock pistons have shallow reliefs, but that shouldnt be an issue on LS cams, the P8R cams suck, they are lower lift and duration probably to keep emmission low and the idle quality up since the intake valves are bigger.

Good luck with your build, probably see you around Im in South Jersey and go into philly alot along with atco and maple grove.

stallinrawlings

Haha - yeah all that's gonna be in what I posted - thanks guys - this is on my phone cause my internet is off right now in the house - I'll post the whole thing today. Keep looking for it.

spAdam

iTrader: (1)

There are a few of us running around with builds similar to this. It's a fun motor if you put it on a gs-r trans.

Mine:

https://honda-tech.com/forums/all-motor-naturally-aspirated-44/mild-b20z-non-vtec-daily-driver-build-looking-input-2932515/

stallinrawlings

What I have:
B20Z2
P8R head milled .010”
B18B1 stock Cams
Brian Crower dual valve springs with retainers from my old p75 head

P75 head Info:
Non vtec
45cc combustion chamber
81mm bore diameter
31mm intake valves
28mm exhaust valves

P8R head info:
Non vtec
47cc combustion chamber (it might be 48cc - correct me if I’m wrong)
84mm bore diameter
33mm intake valves
28mm exhaust valves

^^^ I have yet to find ANY after market valves that fit this head. There isn’t a big enough supporting base for it because it’s not regular. Just so you know. The closest I got were the valves for the b20a5/b21a engines in the 88-91 prelude. 33mm valve with the 6mm valve stem like it needs to be, but it’s about a millimeter and half too long. I was a little salty about it. Luckily the stock valves were fine so I ended up reusing them, but it still sucks.

Things to know:
In stock form the B20Z2 has 9.6:1 compression. This is with a p75 head. The JDM b20 that came with the p8r had 9.2:1 due to the bigger combustion chamber. It also used the b20b pistons. (b20b has 8.8:1 compression). - as far as I know this is correct.

According to wikipedia the P8R b20 has about 6 less hp from the factory than the p75 equipped b20z2. This is due to a couple things: although it has bigger intake valves, it has lower compression AND it’s cams are junk as well. P75 cams, measured from the back to the peak lift point (can’t remember proper terminology sorry), is 1.327”. P8R cams are 1.307” for the same measurement. Yeah that’s a huge difference I’d say. There’s a picture on some forum that shows this. The other reason I don’t think is as big of a reason, but it still helps; 9.2:1 compression vs 9.6:1 compression.

OTHER INFO:
I have a 2001 crv that this is going back into. From the factory the 9.6:1 higher compression b20z2 engine is rated to RUN SAFELY on 86 octane gasoline. Yes 86 octane, you’re not blind and it’s not a typo. I laughed too cause we don’t sell anything lower than 87 in the US as far as I know.

Static compression:
The best compression an engine can ever do; bottom dead center to top dead center compressed into whatever sized combustion space you have.
Effective (dynamic) compression:
When the engine actually starts to make compression. This only occurs after the intake valves start to close. (After Bottom dead center on the compression stroke.)

I did all the math when I built my b18b1 last year. The stock b18b1 cams start to close the intake valves at 16 degrees After Bottom Dead Center. This is, I think at least, one way honda made their engines so efficient from the factory. To put that in perspective; old v8 engines usually start to shut the intake valves at 30-45 degrees after bottom dead center which only allows them to use about 3/4 of the full stroke.

Also, because honda’s (at least b18b1 cams) start to create compression almost immediately ABDC; their effective compression is almost the same. There are effective compression calculators online. I used wallace racing.

B20z2:
9.6:1 static compression
137mm rod length
89mm stoke
84mm bore
4 cylinders
16 degrees ABDC for valve closing

Comes to about 9.49 I think. (go look for yourself it’s pretty cool.)

MY QUESTIONS:
I’ve milled off .010” from the head. This will raise my compression to about 9.6:1 from the 9.3:1 that a direct P8R swap would yield.(according to zealautowerks.com - that’s a fantastic website for anyone who needs to figure out compression for D, B, H, and F series engines. Not sure if they have K yet. Also decently accurate at judging hp - crank and wheel.)

I really want to use a 1 layer head gasket if I can cause that will raise it to 9.9:1 static. (9.85:1-ish effective if I remember correctly)
The fears/issues I’m having:
The B20z2 has slightly higher compression pistons that the b20b, which is the block used for the p8r head.
The dishes are deeper in the piston top for the b20z2. They are designed for 31mm intake valves; I’m using 33mm. The more you mill and take off, the closer the valves and pistons get to each other. I’ll be taking off about .030” total with a 1 layer head gasket and .010” off the head, so will that have clearance issues? I can’t afford to break this engine……

Another thought and question:
If the factory engine can run safely on 86 octane fuel at 9.6:1 compression. If I raise it to 9.9:1 can I run it on 89? Or do I have to go up to 91? I’d rather run 89 because it’s better to run the lowest octane you can without knocking/getting detonation/getting preignition. This is because the lower the octane rating the more volatile/the faster the burn time the fuel is/has. Why does this matter so much? An engine that runs on 86/87 octane shouldn’t be run on 93 because YOU ARE LOSING POWER. It burns too slowly and isn’t as efficient for the amount of compression you’ve got. I seem to also lose fuel economy as well, but that’s a lot harder to prove that it’s effected by the octane rating as far as I know.

And I used to run my D16Y8 on 89 cause it ran a hell of a lot better, smoother, and had more pick up and go. 87 works for it, but not nearly as well. At least with mine that is.

I’m also curious about the manifolds:
Are the runners in the b18b1 intake manifold wider/bigger than the ones in the b20z2? I have the power chamber-thingy manifold. NOT the giraffe. I’d like to reuse the sotck manifold but I do have a b18b1 manifold if need be.

By the way, the 2001 5speed crv is rated at 19 city/23 highway fuel milage. I’ve managed to get about 25mpg out of it by nor revving it past 2500 unless I’m on the highway cause the gears are a little shorter than an b18b1. That’s about 50/50 city/highway.

Thanks for reading, hope this helped some and prompts others.
I’d appreciate any input,
Thanks guys.

stallinrawlings

the crv wieghs about 3200 lbs from the factory so i'd say that's decent milage considering (and AWD).
and spAdam and DA-NINE -- thanks guys, looked at your posts real quick. didn't get a chance to read them fully, but that's really good stuff.
just so you guys know; a vtec head will basically always flow better. that and the angles of the ports/port design is just generally better... I actually talked to Larry Widmer at Energy Dynamics in Texas about this. he has a 300whp b20vtec with no boost that puts out about 200wheel torque. 84.5mm bore, dart block, etc etc. go to his website and READ. The man has been building engines for years, and HE KNOWS what he's doing. He built the winning Nascar and Indy car engines for Ford in the 70's and 80's. http://www.theoldone.com/

i was originally gonna do a Jackson Racing Super Charger Build with the p8r head, but he explained to me why i shouldn't:
the one that was used for the LS style head is really only suited for a D16; just doesn't push enough air. that and it gets hot and you loss power down the road. quite literally haha. (it's a twin screw style super charger.) and if you want to fit the one made for the b16 on it you've got a huge headache on your hands. i was a little disappointed cause i love a supercharger... he said "Most of what I've done has been trial and error; i try to help people to not repeat the same mistakes I've made myself."

DA-NINE

If you are going to take the time to assemble a motor of this nature its worth it to get the head done how you want it then clay the motor to find your clearances,


As far as i have seen there is about .1" of P2v clearance on a bone stock b18/b20.
.100
-.010
--------

3layer hg= .026"
-1 layer hg= .0096"
---------------
= .0164" less.

=.090" p2v
-2 layers of HG= .0164

leaves you with= .0736" of breathing room.

DA-NINE

As far as octane goes. from what I know, since the burn rate is slower, you can advance timing and have the combustion pressures increase over a longer amount of time. thus more torque and power. so id tend to beleive that if you were to go and get the engine/car tuned on 89 octane then have the tune touched up (optimized) for 93 octane the motor will probably make more power.

spAdam

iTrader: (1)

A couple of dial indicators and a simple checking fixture are MUCH better than clay for measuring clearances. You can actually map the clearances all the way through the crankshaft range near tdc and know if a cam is going to work before you ever put it in the motor.

stallinrawlings

Thank you for the I go guys. And the reason why I'm asking is because I do not actually have the required equipment to measure this myself. The engine is in the car already; I'm swapping the head in myself cause I can do that much at least. And I just want to make sure here; are you talking about the b20b or b20z? Cause the pistons are different, that was the basis of my concern.
I figured I'd be ok, but I wasn't going to do something foolish and ruin my motor.

EsotericImage

iTrader: (8)

youll have plenty of room with the P2V. They have 47cc chambers.

Finding an OEM HG in 2 layer is rather hard to find. Cometic would be your best bet. Im using OEM 3 layer and my crush thickness is .023 with ARP's

I have a N/A B20 P8R build in my profile.

P8R shaved 15
DIY Port blending
Crane Ti springs and retainers
Crane 0016 cams
YCP ITR Replicas
11.2:1 CR
ARP rod bolts and headstuds

166WHP/142Tq

stallinrawlings

Does anyone know if the intake manifold runners are smaller in the non-giraffe manifold compared to a 97 LS integra manifold? The one with the power-chamber-air-box-thingy up top lol

spAdam

iTrader: (1)

The PHK manifold is VERY similar to a P75 when you pull the box off, I have not done any formal measurement though.



Note: The angle of the photo makes the plenums look like they are a different shape/size, but they are actually nearly identical.

stallinrawlings

Sorry if I don't call you by profile name (I'm on my phone and I can't reply and look at the names at the same time) - but thanks; I thought as much with the phk manifold. And also thanks for the advice on p2v clearance with the p8r head. Nice numbers too man - obviously I won't have that much, but with a header (haven't gotten one yet), p8r head with b18b1 cams, and a slight compression increase I'm hoping for 10ish at the wheel maybe.
Also, if you guys want better responsiveness out of your builds? I'd highly recommend an msd ignition setup - stock honda distributors from the 90's (at least with the internal coil I know), have a voltage output of about 8k-12k volts. The msd brings up to about 25k. Modern cars have about 60k but that's coil on pack and such. I had the 100-120 dollar coil kit on my stock b18b1 dizzy when I had my b18b1 powered coupe and it was really nice. You remove the internal coil, and solder wires to extend the stock ones, run it to the outside of the dizzy (I did it through the whole where the stock wore group runs anyway), and attach them to the corresponding spots on the external coil. Not really hard at all and I'd say it's worth it.
My setup was this:
(Unless stated otherwise it's stock)
B18b1 bored out to 81.5
Eagle stock spec crank (mine was warped)
Crower stage 1 cams
Super tech valves
Brian crower dual valves springs, and titanium retainers
Megan racing header
Apexi 60mm gt spec exhaust
(I swear everybody wanted that exhaust - it sounded better then most things)
Apexi active tail silencer
(Quiet for daily driving and then when you got on it the spring loaded pressure valve in the silencer opened up letting more air through. - it was the best. Period.)
Msd ignition
Stock obd2a p75 ecu
Aem intake
Also had eibach sway bars front and rear (26mm front/17mm rear) with the as rear subframe brace
I miss that car - but that's how I know the msd is worth it - plus you won't fry your dizzy if you pull a plug or something. The stock ones always have that happen cause when you pull it off while running it tries to up the voltage to jump the larger gap, and it ends up jumping from the coil itself over to the igniter/ignition module.

stallinrawlings

If a car has more power but is sluggish it won't be as nice - there's a video on YouTube of an online 6 shoot out on the touge track in japan - there's a supra and a few gtr's - tscuchia is on it. Well there's a Mine's 34 with the same power as the rest (it's a 280ps class - the Japanese measurement for hp which almost the same) - the mines gtr wiped the floor because it was so quick to rev and had all it's power from probably 2/2.5k to about 8k - tsuchia said himself that the car was TOO fast. It was out driving the track.

stallinrawlings

OK so I finished the head swap @4am Friday morning and I've got about 150 miles to go on head gasket break in.

Here's something weird:
At a red light about... 15 minutes ago I stalled because it snapped back at me cause I've got bad engine mounts. (I'll get some soon!)
Well when I started it up again? It ran BETTER. Better than even before the swap I might add. Smoother, less noise, quieter intake/exhaust sound, slightly better pickup etc etc. And as far as I can tell the gas mileage went UP. Yeah I know that's crazy but parked on level ground the gauge went up 2-3 millimeters.
The only explanation I can even fathom, because I checked and nothing seems to be broken or missing, is that I had bad cam timing to begin with and it jumped a tooth correcting the problem... For starters the cams were probably 3-4 degrees retarded because if the millin and arp gasket crush. That being said it was a bit less powerful under roughly 3500rpms. So I'm just wondering if that would make sense???

stallinrawlings

Thoughts welcome guys.
I will also see what happens as I continue driving.

yaqubabdula

What is that big hole on the left side manifold??

m4xwellmurd3r

Theres a resonator box on the b20 manifold that goes there