The J3X guide. Block, crank, rod, piston combinations.

[NVA-AV6]

There are 2 blocks out there that will both bolt up to our trannys and support the 7th gen sensors. These are the stock J30A4/5 of course and the J32A3 from a 04-06 Acura TL, thgis block will give you a 89MM bore vs the stock 86MM bore. Also the J32 block has steel sleeves vs the FRM sleeves of the J30 thus making them stronger and better for low boost applications, I would not boost above 10-12lbs. on any of the blocks without re-sleeving.

I always suggest getting the crank and rods as a matched set and not mixing from different vehicles. Our stock crank has a 86mm stroke as does the J32, the J35A5 (03-05 MDX) and J35A8 (07+ TL-S) both have 93MM Stroke and the J37 (06+ MDX) is 96MM stroke. It was nice for honda to keep the internal crnak case desighn the same across all J blocks, thus making easy to put different crank & rod combos into the blocks. The J30 crank is a cast part wheras the Acura parts are forged, but don't bo fooled, although they are forged and stronger than the J30 parts, that does not mean you can run 30lbs of boost on them, they are forged primarily to reduce weight.

Pistons, if you are using a J30 block, your only option other than stock is to go custom or J30A1 pistons, these would give you a 9:1 compression ratio. If using the J32 block your options open up quite a bit with the 89MM bore. These options would be 04-06 TL pistons for a 10:1 compression ratio, 03 CL-S pistons for a 10.5:1 copression and 05+ RL or 07+ TL-S pistons for 11:1 compression. Also the RL/TL-S pistons are also factory forged componets.

Now, what you get combining thesed together.

J30 Block + J35 crank and rods = J33- 3.3L displacement  
J32 Block + J35 crank and rods = J35- 3.5L displacement  :twisted:

The nice thing about the J33 & J34 is you keep your stock block and block codes, therefore it does not change your warrenty since unless they take the engine apart and look no-one can tell that is has been upgraded.

[Mike]

What is the cost of the J33 compared to the J34, and what are the proformance gains of each.

[NVA-AV6]

J33/J34 are aroung $4.5K ea, there really isn't much of a cost differentce anymore, same with the J35/J36, the MDX crank and rod set are about the same price as a J35 crank and rod set, now it is anoth $600 to goto a J35/J36 since you need to buy a J32A3 block.

[rich]

i just want the new J35 TLS motor with the comptech supercharger   :!:

[Blackhawk]

J37 Crank and rods here we go!

[Stheman]

J36 already installed waiting on eaton M90

[Fenix]

this is very useful information. If i only had the kablingy to do this.

[kSchwiggy]

 


translated: my J35 is awesome

[Mr Eazy]

Awesome info Paul. This definitely sheds light on where my future funds will go, you will be hearing from me in the future. Hopefully sooner rather than later.

Question: The new TL 3.7. from your write up, it would need a new tranny, correct? or would the OEM 6spd work? or if it won't work, is there a 6spd that would?

[NVA-AV6]

The new 3.7 will not bolt up to ure trannys, and I don't know what 6spd if any will, this is why I keep referring back to using a J32A3 block.

[Mr Eazy]

The new 3.7 will not bolt up to ure trannys, and I don't know what 6spd if any will, this is why I keep referring back to using a J32A3 block.

Cool, thanks Paul

[Fenix]

Arie you thinking of some changes?

[Mr Eazy]

Arie you thinking of some changes?

Of course  

Only one thing stands in my way: $$$$$$$$$$

[mschumacher]

Interesting.

Are the main/rod journal dimensions the same across the J30A4 and J32A3? As in, swapping a crank being possible or not. Assuming the Honda crank is cast and not forged. I'm kind of surprised that the crank is cast. Even the lowly D15s from Honda had forged cranks going as far back as 1988. I have no knowledge of their engines before that era so I cannot comment on that. Shocking, really.

Secondly, would you have the combustion chamber volumes of the J30A4 heads? And piston compression height and dome/dish displacement? Seems like either nobody is willing to share this data or I've been looking in the wrong places.

Sucks that we got the heads with the retarded exhaust port. I know firsthand what a good set of pipes can do on a lowly D15, so designing a set of headers for a V6 would've been FUN.

Possible to swap any other head on the J30A4 block? Does ARP make head studs and rod bolts for this engine?

I read somewhere about people swapping TL-S (apologies if I've mixed up some alphabets) cams into this engine. Does that have a marked difference when compared to the stock cams?

Is there any data available on the stock cams (duration, lsa, lift, rocker arm ratio, etc)? If not, and if anyone can spare a single cam, I can have it shipped to one of my friends for a complete Cam Doctor report.

I'm surprised at the relative lack of support for these engines by aftermarket companies. Custom parts are way too expensive and a PITA for someone like me who doesn't live in the States.

Guess it'll have to do.

Thanks and sorry for bumping a 4 year old sticky lol

[Rich01]

Regarding my post in your thread...i guess you do have a little more than average mechanical know how lol. Create a profile so we can give you an official welcome to the site.