J32A2 specs and options?

[BigJ]

I have been toying with the idea of building a hybrid 32a2 and 35a1 but when I really started looking at the 32a2's components the stroke yeilds ultra low piston speeds and has a near perfect rod stroke ratio. So good in fact it is better than a b18c5!

Information I have found to come to this conclusion
Stroke 86mm
Rods 152mm

If these numbers are true then the piston speed at 8600rpm of the J32 is slower than an H22 or B18c and even the famed f20c at factory redline! And with rod/stroke ratio of 1.767 it is as rev happy as any b16 having a great rod angle.

Outside of breathing what is there to look at on the J32? I will be going with itbs and I already have an ok header to start with. I know the valvetrain needs beefing up with the obvious springs and retainers and probably a custom cam.

Would I need any additional block stiffening? The J32 has signifactly more block stiffening ribs than any other j block produced in this era (2nd gen).

Should the rods be of concern? From all of the 4cyl history i have had Honda's motors are stout as hell so I feel pretty comfortable with factory rods and piston right now.

Soooo, am I a pie eyed rev happy lunatic with a stupid idea and should stick to my original idea of a 32a2/35a1 hybrid or am I on to something here?

[wolydotmatrix]

J32/35 build in process. Just waiting on $$$$ for bearings. I believe this setup should yield some great #"s. GL with your build. Welcome to the forum.

[acidbath124]

i think i am going to do that build as well. i hav an odyssey crank i bought about a year ago and another motor to do it with so i dont have to have the car down for the build. i beleive i am also going to use an ITB setup one thing i need to find out though is what can be done to raise the compression other than using the rl pistons and if it would be a bad idea to lighten the crank any. any opinions are welcome

[wolydotmatrix]

have the crank knife edged and then send the entire rotating assy to the machine shop for balancing due to the weight decrease. (crank, rods, pistons, flywheel, clutch and pressure plate) will need everything if they know what they are doing.

Compression: you can mill head or block. Or remove inner layer of head gasket.
custom pistons or flat faced vales will work also.

[IDon'tKnow]

I don't know how this misconception got out there, or if I'm just missing something, but the RL pistons should actually be lower compression than the TL-S pistons.

J35A3 Compression ratio is: 11:1 so 3500cc/11= 318cc chamber volume at TDC.
J32A2 Compression ratio is: 10.5:1 so 3200cc/10.5= 304.5cc chamber volume at TDC.

So unless the chamber shape the the J35A3 heads is different than on the J32 it stand to reason that the J32 pistons have a higher dome.

304.5cc chamber volume at TDC with a 3500cc engine should yield 11.5:1 compression.

You can bump your compression up by running flat face valves, shaving the head, or just running a single layer of the factory head gasket (which is .75mm thick from the factory with the middle layer being just .2mm), or you could have the chambers filled in a bit to add quench area thus removing chamber volume at TDC. (Think GSR head instead of B16 head)

Also keep in mind that static compression ratios are not the same as effective compression ratios because of valve overlap.

[acidbath124]

from what i understand you have to use the rl pistons cuz with any of the other ones the valves would hit or something is what i have been told

[JCharged]

^ Yes they have the valve reliefs on the piston.

[IDon'tKnow]

^ Yes they have the valve reliefs on the piston.

If the deck height is the same on both motors (which everyone seems to think is the case) then there should be no difference in the extent of the valve reliefs or the need for them.