Frankacura

I just got back my P8R from RaceHead and Carlo did the last tutch to my P8R that was just waiting for it
The last numbers are wit my PR3 Polish IM on the head... 90% efficacy



Here a stock Si-R pr3 head flow.

Frankacura

Frank Ported P8R

Scott_Tucker

Looks like you're good to about .500" valve lift. What kind of cam are you running?

Frankacura

Crower 404's and a B20Stroked

Scott_Tucker

What is th valve lift on those cams? On their website it looks like about .425" or .450" but that spec may be cam lift?

Frankacura

62404-2

Stage 3 - 3/4 Race, recommended for mostly strip.
Requires #84162 kit and ECU mods.
1100 to 8200+ rpm, lope at idle.
ADV. 276 / 272 DUR.
445 / 434 Lift.
But i mesured 11.46mm/10.8mm at the cam X Rocker Ratio

gutted-dx

iTrader: (1)

Why not 405s?

Scott_Tucker

11.46 mm at the valve would be .451". If you look at your flow graph, your flow starts leveling off about .475". You could probably gain by getting a cam with more lift. If the head will flow more by lifting the valve more, why not? Also, you need to have the intake valve open to the point of max flow (which is roughly .475") by the time the piston reaches maximum velocity. This will be around 70 degrees after top dead center (ATDC). Therefore it is advisable to have your peak lift a little higher than where port flow levels off to insure that it is open at least that much by the time the piston reaches maximum velocity. A cam with about .500" would probably work well in this head.

If you look at your stock head, flow starts leveling off about .350" so if you were using this cam on a stock head you would have plenty of lift (actually, a little too much).

Frankacura

The first numbers are not stock head but ported no valve job.
Im running one of those ported no valve job head now on stock b18b cams and make 160WHP
Those nonvtec head use to flow 210CFM So i dont really care about gething bigger cams. they all ready gonna rattle at idl so its my daily driven car
But ill take note of your tuning tecknick Also note that my head is flowing as a H22 head at .300 lift 223CFM

092eg6

whats the stock flow numbers?

Scott_Tucker

Yeah, just something to keep in mind if you decide to get new cams. Its not so much the lift that is going to get you at idle as it is the overlap.

What is your static compression ratio? My only additional though would be that since that head flows so much more than stock that you may kill velocity at low rpm which is only going to contribute to a rough idle.

mavvrik

The biggest thing that's going to affect idle is your overlap. Larger the overlap, the nastier it sounds. Like Toda's, for example, have a real high overlap, that's why they make your car sound like t's gonna idle out :/

Frankacura

The velocity is not killed cause this head was way far from an Si-R head and now the ports are still smaller than the vtec one. this is the raison for 223CFM at .300lift. Big velocity is pushing air in the small opening.
I enderstand that over lapp is killing the low end but if i get the 405 they have more over lapp. so unless i get a paire of custom regrind i cant just raise lift on same duration...
Im 11.4:1CR
B20 84.5 DART bloc 226mm deck hight
-97mm Eagle restroked crank ( 2.180L)
-151mm Rods
-Flat pistons -4cc notch for 11.4:1 P8R head shaved .020
-P8R head Ported/flowed at:
- Ported Si-R ( P30 ) IM 63mm Throttle body
- B18b 95 intégra Intake cam B20b 97 JDM ex. cam
- AEM cams gears
- Stock valves
- Modified LS air box wit Stock filter (ran my old LSVTEC set up at 202Whp)
- Tri-Y headers, 15" of 2 1/2" exhaust line at headers and 3" balance
- 3" reson and 3" muffler No cat ( same than my old LSVTEC set up)

https://honda-tech.com/forums/all-motor-naturally-aspirated-44/my-nonvtec-b22b-frankenstein-2658830/

Frankacura

Carlo did'nt got the time to flow the stock one.
numbers are coming in copuple of munth.
i guess Max 225cfm@.500 at .300 maibe 185cfm@.300 stock
For those that think i kill the lowend by increasing so much the flow.
Look at the pic and its not looking so big.
I have to tell you that this head usualy have smaller ports that the normal P75 ou Pr4 one. P8R Its a Accord station wagon head... Tq at low rpm.
And valves are not 31mm as tha p-75 but 33mm as Si-R vtec one that flow 255cfm. Im 260 on valve job... (velocity is at home) LOL

Frankacura

Hoo yes also...
this head use to fead a 2L bloc now its a 2.2L and this head have beene donne to run 120Whp@6200rpm on those stock ports, i want 220Whp@7800rpm...

Frankacura

Can't wait till March to tune the motor...

Frankacura

If annibody have some flow numbers from anny other P8R head that is ported or not. Would be nice to see it and have a compare. ( P8R or P-75/r4)
lets post it.
even can take some compare wit Si-R/GSR vtec head..

flesh199

You can not always compare flowbench number.

Cant wait to see some traps mph from your non vtec build

Frankacura

Yess it will be tested at the track. the track dosnt lie
I guess Or hope at least 110Mph

vwbased

Have a nice day

Frankacura

Woww ! The P-75 have verry nice numbers for a 31mm valves.
Unbelievable
Is that head run actualy ??

vwbased

Have a nice day

Combustion Contraption

VTEC heads can get away with bigger ports because of the variable valve timing. With a big port, to keep the engine from losing all its low end power, you keep duration short, and the lift low. And thats what the non-VTEC lobe does. How do VTEC engines idle when you install VTEC "killer" cams and really show how big those ports are?

Frankacura

I anderstand, but if using Killer wit smaller ports and longer IM youll be Loping less at idl.
But loosing at top end.

Frankacura

Verry nice the VW project
It most take off like crazy...