Hey all, man about 25-30 hours of swaping parts motor to motor and one out and one In, finally done. Fired it up tonight, ran ok, has a wierd electrical problem which I will be facing tommorow. It seems to draw a hell of alot from the motor every cycle. Drops the motor to about 200rpm from 600Idle. (Have to adjust timing). But anywas my main question is seeing how the head flows better than A regular B20/LS head will I need a FPR for sure? I might get it dyno tuned - well semi tuned with a chipped ECU but was wondering? anyone with a head like this built? or not even let me know.. Thx all. Road test to come soon. Gotta break in new clutch first!

 

B20B road Review! Well.. I Can truly say that it is about what I expected. The midrange is decent and Top is a little, well im not sure If I got LS cams in it or not. Does anyone know if there is a difference between The cams /w In 75/Ex 75 stamped on them and P4/P1 stamped on them? the 75's I got from the B20 with the P8R head and the P's are from the Ls motor I just pulled out. When I took it up past 6k it felt good like my LS, a LITTLE sluggish but it needs to be tuned, timing is just at a guess right now in the middle. (No light right now). Other than that, stock LS tranny blah, but third seems to pull alot harder for sure. If anyone knows about the cams let me know or else comments are appreciated

 

sorry forgot to add a question, does anyone know the Gap for the plugs on a B20B? I just got my stock NGK LS plugs gapped to the spec in the owners Manual. This could be affecting my power a little im sure. thx.

 

bump!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Darkane &raquo;</TD></TR><TR><TD CLASS="quote">B20B road Review! Well.. I Can truly say that it is about what I expected. The midrange is decent and Top is a little, well im not sure If I got LS cams in it or not. Does anyone know if there is a difference between The cams /w In 75/Ex 75 stamped on them and P4/P1 stamped on them? the 75's I got from the B20 with the P8R head and the P's are from the Ls motor I just pulled out. When I took it up past 6k it felt good like my LS, a LITTLE sluggish but it needs to be tuned, timing is just at a guess right now in the middle. (No light right now). Other than that, stock LS tranny blah, but third seems to pull alot harder for sure. If anyone knows about the cams let me know or else comments are appreciated </TD></TR></TABLE>


I'm wondering the same thing. I have a B20b and both cams say IN 75 and EX 75. Does that mean they are the P75 cams?

 

I don't know about the cams, but I just did that swap myself\
3rd gear definitely pulls harder

my idle is also very low... did you use the IACV from the B18 or the one from the B20, I used the one from the B20 and I think that might be the problem

 

That's funny. You put an LS head on a B20. Why?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by You_Get_Vapors &raquo;</TD></TR><TR><TD CLASS="quote">That's funny. You put an LS head on a B20. Why?</TD></TR></TABLE>

P8R head is not the same thing as an LS head.

Its got bigger valves and 84mm chambers.

 

My bad I musta got confused. So where is a P8R head off of?

 

Just a quick reply on the fuel. I am running a US 2001 B20Z in my delSol with a 96 LS ecu. It was coming up lean all the time. The long term fuel trim was ranging from 14% to 19%. So I just bought some 97+ Prelude injectors, drop in for my 97 delSol. And it runs great now! It is never lean and we did a WOT run on the freeway and the fuel was just above the stoich. point. We were running .935 volts on the O2 sensor which, was just a little rich. But I'd rather be a little rich than lean!

- Octavious

Look here for more info.
https://honda-tech.com/zerothread?id=460954

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by You_Get_Vapors &raquo;</TD></TR><TR><TD CLASS="quote">My bad I musta got confused. So where is a P8R head off of? </TD></TR></TABLE>

Its only available on certain B20 blocks in Japan.

For pics go here:
https://honda-tech.com/zerothread?id=796878

 

originally posted by blueteg:

P8R head is not the same thing as an LS head.

Its got bigger valves and 84mm chambers.

I thought the ls head and b20 head both were identical....both used p75 heads (and some p8r heads) and they both have 81 mm combustion chambers...just the blocks were different. if they were different...they would come with different stampings on the head...but they're both p75 heads. the only difference is a slightly different intake came in the U.S. b20b.

 

Actually no, P8R heads are different and do have a different casting and stamps. Look at the pics. Also I belive the Blocks* are the same. Mine is stamped P3F so being a Low CR bottom end. Im not sure how much the valves/ports/84mm Chamber do on the stock cams, but I got some 404's on order and I will Dyno them so Ill let you guys know how that goes , And on a side note I think i will be doing Hondata for tuning. Anyone have other suggestions?

 

yah...sorry ur right.
after doing a little research...i found out that there are a few different b20 heads.
There's the ls head, the P75 with the 81 mm combustion chamber and smaller valves.
there's the P8R head with a 84 mm bore and much larger valves..
then there's the P3f head which i don't know what's in that.

I don't understand why honda put so many different heads on a b20b. After searching about the P8R head, i came to find out that it is supposedly the rarest of the b20b heads and the best non-vtec b series head with it's much larger valves and 84 mm combustion chamber. I was intrigued by this and went out and popped the hood on my crx to see that my b20b head was stamped P8R. All this time i just thot it was the normal 81 mm b20 head like my friends. he has a jdm b20b and his says P75 on it and im assuming it's a 84mm block with an 81 mm head which might be the reasoning behind the JDM motors having a slightly higher compression? all this has got me thinking...

here's my head:




Modified by bambam at 7:59 PM 7/4/2004

 

P3F is the block of the low CR piston, PHK is the high Cr piston. Its stamped well on the back of the block. The only other head that could potentially be on the b20 is the PR4 head off some gen3 tegs but mostly gen 2's.

 

I had no idea there were so many b20 heads, I'll have to check mine to find out whcih one I have

Octoman: were you running LS injectors before the Lude injectors?
and by lean, did you also have a shitty idle?

 

I'm wondering...could it be that the b20's with the P8R head are the 8.8 comp. motors? And the ones with the p75 heads and the P3F pistons are the 9.2 ones? Then the ones with the P75 heads and the PHK pistons are the 9.6 ones? How can a b20 with a P75 81 mm head have the same 8.8:1 comp ratio as a b20 with a P8R 84 mm head? wouldn't the compression be higher with the P75 head? Also, what bore are the P3f cylinder heads? Are all B20's with a P8R head considered "JDM"?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bambam &raquo;</TD></TR><TR><TD CLASS="quote">I'm wondering...could it be that the b20's with the P8R head are the 8.8 comp. motors? And the ones with the p75 heads and the P3F pistons are the 9.2 ones? Then the ones with the P75 heads and the PHK pistons are the 9.6 ones? How can a b20 with a P75 81 mm head have the same 8.8:1 comp ratio as a b20 with a P8R 84 mm head? wouldn't the compression be higher with the P75 head? Also, what bore are the P3f cylinder heads? Are all B20's with a P8R head considered "JDM"?</TD></TR></TABLE>

I think But not sure that our motors might be 9.2 because mine looked like it had a 2 layer headgasket. the 8.8CR has a 3 layer, but i could be blind dont quote me as for P8R being JDM it is and only JDM. No such thing as a P3F head, just P75, P8R and sometimes PR4 if switched from a B18. P3F is the block code for low CR.

 

I wish there were alot more information on this...No one seems to know anything about this P8R head thing. I've searched Honda-tech and come up with minimal results...it's mentioned few times and when it is...most people reject it as a RARE JDM head with 84 mm combustion chambers and vtec sized 33 mm valves.

No one know's that the b20's all come with the ls head w/ 81 mm combustion chambers (except w/ the P8R head). Everyone ive talked to thinks that the b20 head is different than the ls head but it's not. They think that all B20 heads have an 84 mm combustion chamber. But the only B20 with the 84 mm head is one with a P8R head. That's funny. So, that means that all the B20's with P8R heads are REAL JDM motors right? My friends all swear that my B20 is a U.S. B20 and I'm trying to tell them it's not. My friend has a B20 that came with the wiring harness still attached and it was definitely from Japan because the plugs for the ECU were still attached and they came through the firewall on the opposite side of the wall as U.S cars..on the right side of the engine bay. His B20 came with a low-rise manifold and a P75 head...
anyway....i really wish there were more information about this and it sux not knowing what Comp. Ratio my motor is...9.2 sounds about right tho.


Modified by bambam at 4:53 PM 7/6/2004

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BigC-ivic &raquo;</TD></TR><TR><TD CLASS="quote">I had no idea there were so many b20 heads, I'll have to check mine to find out whcih one I have

Octoman: were you running LS injectors before the Lude injectors?
and by lean, did you also have a shitty idle?

</TD></TR></TABLE>

I was running B16 injectors from my 97 sol, so they were 240s just like LS injectors. The idle was not bad, it held a steady 750 rpm. My only problem was that at wide open throttle I was running real lean! I have an OBD2 scan tool and I was able to check the long and short term fuel trim. I wanted to keep the OBD2 so I would not have any trouble passing insoection. So with it came problems, not enough fuel. The long term fuel trim would range from 14% to 19%, for those that don't knwo what long term fuel trim is, it is the percentage of fuel automatically add or subtracted by the ECU. It learns this from the short term trim, which is monitored from the primary O2 sensor. Since I could not add fuel by moddifing the ECU I ahd to look for larger injectors or a FPR. I choose injectors. Many say that the Lude injectors range from 280~290cc and thats about right. The fuel injectors have made the car smoother running and have got rid of my lean condition at wide open throttle. They are definite must! I also think that 270cc is to small, you need at least the 280ish from the Lude injectors. I checked my O2 ratio and it runs a little rich, which is good.

As for the P8R head, here are my thoughts. There is a honda.co.jp website that shows a car with a B20 that is making as much power and torque as the US B20Z.<U>BUT</U> it has a 9.2 compression ratio. This could be the P8R motor.
MY car has a 2 layer head gasket, I counted them myself. But has 9.7 compression ratio. The chambers in the P8R are larger, so this would account for the lower compression ratio, but the power is made back up by a better flowing head.

Go to:
http://www.c-speedracing.com/h...c.php

plug in numbers for B20Z with PHK pistons, 2 layer gasket and a 49cc chamber and you get 9.2 cr, the stock LS/CRV head chamber is 45cc. See the difference.

Here is the link to the CRV with what I think is the P8R head:
http://www.honda.co.jp/HOT/Mod....html





Modified by Octoman at 6:56 PM 7/9/2004

 

So now we can officially say that the LS head and the B20 head is not the same as everyone thinks that it is....

too bad i gave you the motor to you Jordan. Lucky ***!!! Anyways, if i was ever worried about how my head flowed, i'd just send it to IB to get it done anyways.... lol

 

so you finally admit it!!!
lol.....j/k

hey armand...I was thinking...remember that you said u originally sent out ur B20 head to Import Builders...and it was a different head than the one you got back?
If it wasn't a P75 head then it had to be the rare PR8 head that u sent them....I think they saw it had the 84mm combustion chambers and sent you back a built LS head thinking you wouldn't notice....those b@stards!!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bambam &raquo;</TD></TR><TR><TD CLASS="quote">so you finally admit it!!!
lol.....j/k

hey armand...I was thinking...remember that you said u originally sent out ur B20 head to Import Builders...and it was a different head than the one you got back?
If it wasn't a P75 head then it had to be the rare PR8 head that u sent them....I think they saw it had the 84mm combustion chambers and sent you back a built LS head thinking you wouldn't notice....those b@stards!!!</TD></TR></TABLE>


Nah not necessarily.... I sent them Ben's stock LS head as a core so that they would send me one of their kits. SO lol but other than that, when i was working on your "rare" engine, i always wondered why swift was telling me that the combustion chambers were different..now i know why. but still though... all these cylinder heads are all interchangeable but it all comes down to what head that you want to use.

 

interesting......

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by XtremeCarTuner &raquo;</TD></TR><TR><TD CLASS="quote"> So now we can officially say that the LS head and the B20 head is not the same as everyone thinks that it is....

</TD></TR></TABLE>

That is some what inaccurate to say, as most B20s do use the LS head, only some, hard to find ones, use the P8R head. Also I believe that one of the cams for the US B20Z has more lift that the best LS cam. Can't remember where I saw it though,will look for reference and post back.