what about knife edging the crank ? is it worth it ?

 

knife edging and lightening the crank is definitly worth it if done right.

 

Oddy: 10:1
J32A2: 10.5:2
RL: nobody knows what it is in our block with our head configuration

I've had all three pistons side-by-side for comparison, and I can tell you, there was no visible difference between the combustion side of the J32 and the RL. There are well-known rumors circling that they are higher comp than the J32, but in my experience, they are not. Though in the RL motor, compression is listed as 11:1, that may not be a result of the pistons, but deck height.

If you don't plan to run boost, assembling the block with a set of j32a2 pistons would be worth it, and it'd be a fun little car to drive daily! Sometimes I wish my J35 was NA.

 

I dont think i will take ody shortblock apart just swap the pistons... As long as it will work. J35a4 shortblock with j32a2 heads with no modifications right?

 

Dont the J32 and J35 blocks have the same deck height?

 

Yessir, it is a direct bolt-up.
Well, deck height is a combination of stroke, piston dome, and heads. While the blocks between the J32 and J35 are the same, the RL heads are different.

*edit: I've never had a set of RL heads in my hands, so I can't speak as to what the differences may be, but I can guarantee you that the combustion side of the piston is identical to the CL-S. Heck, the valves could be the difference.

 

wont work with out at minimum mchning the pistons to clear the bigger exhaust valves in the heads

 

This is the myth we have been discussing. Contrary to what the quoted OP says, no modifications are required to run the J32A2 heads on a J35A4 short block.

 

Deck height is the distance from the centerline of the crankshaft to the deck of the block.

 

Lol

There are three different "deck height" types: block, piston, and compression. You defined block deck height, which is obviously not the one I'm referring to in this case.

In the same block (as in this case), block deck height is constant, but piston and compression deck heights change. Piston deck height is measured from the piston dome at TDC to the deck edge (obviously), and depends on rod length, stroke, and piston dish. Compression deck height is measured from the piston dome at TDC to the cylinder head dish, i.e. combustion chamber height.

 

Thank you for clarifying. When you mentioned this:

I automatically assumed you meant block deck height.

When you were comparing pistons, did you measure wrist pin location?

 

I should've been more clear Morgan, sorry about that.

I didn't own a micrometer at the time that I had the two pistons side-by-side, so no, I didn't get an exact figure on the wrist pin offsets. In retrospect, I wish I did.

 

myth ? the valve pocket for the ody piston is smaller than the exhaust valves on the type S head ... does this not = bent valve ?


i know this my oddy short block had the pistons modified

 

The exhaust valves are 30mm on both motors, so there is, and never was, talk about an issue with the exhaust valve reliefs clearing.

But yeah, in regards to the intake valve difference between the two preventing a head swap - myth. I assume you had your Oddy pistons machined because of the information on the internet, not because you puttied the heads and found the reliefs to be too small?

The last time I swapped a new bottom-end into my car, out of curiosity, I personally puttied the heads before I swapped the pistons out. There was almost 1mm of clearance before there would be any piston-to-valve contact.

 

^ Got to love that, reducing compression for no apparent reason.

 

interesting ... now that you mention it ... it is the exhaust valves that you worry about most ... i had it backwards on the larger valves ... so the ody pistons have reliefs bigger than was needed ?

does this also mean that i can just swap say 04+ TL type S heads onto my '07 ody ?

 

It's not that the valve reliefs were "bigger than needed," but it's a combo of a few things. The valve difference isn't actually a full mm (35.51mm vs. 36.0mm), and the J35 pistons are a lower comp so the compression deck height is larger. From the naked eye, it would appear that the valve reliefs would never clear, but the illusion is due to the dish, making the reliefs appear very small as compared to the J32A2. This is probably the reason the "myth" was spawned.

I wish I could speak about the newer J configurations, but I don't have any personal experience with them.

 

I recently bought a Cl s 6mt i am interested in making good reliable n/a power looks like the 3.5 01 mdx block with 05 rl pistons and cls J32a2 heads is the way to go and i had a couple of questions i am interested in getting some comptech headers and wanted to know if the j35 is any taller than the j 32 and would the headers work also what types of tuning are available/ reccomended any advice please let me know thank you i have access to a shop and have some good experience with building engines and for what i cant do i have friends that can thank you let me know

 

This is pretty neat...I am in the Legend community mainly, and the most popular thing are the C35A Type II hybrid swaps, I used to own J series V6's Honda's, but, they have come and gone and the Legend has stayed. This makes me slightly interested in getting an Accord V6 (6th gen coupe, the best looking IMO) and doing something either J35 or J37 with it...b/c except for the newest 2013 Accord Coupe, I can't stand the newer Honda styling.

 

I was wondering if you can use the mdx crank and rods in the j32a2 with the 05 rl pistons only reason i ask is i saw that the internals of the mdx are forged are the rods from the mdx forged? and will they work along with the crank in the cls engine thanks

 

Theyre not technically forged. They are, however, better then the Honda internals.

 

with the 3.5 build can you use the 05 honda ody parts i can get those cheaper than any thing else around here

 

If you used the 3.5l Odyssey block, they have FRP sleeves IIRC, which are weaker then the iron sleeves in the J32A2.

 

are the j37 rods and j35 rods the same?

 

No, they're not. J37A rods are shorter because the stroke is longer.

It's staggering how much misinformation flies around here given out by people who are looked at as those to know the most. Simple concepts like compression ratios and deck heights are just botched and garbled.