cmullins

INTRODUCTION
I have recently decided to stop creeping from the shadows and decided to set up an account with Acurazine. I used honda-tech for years, back in my younger years as experimenting with civics, integras, and such. I decided to graduate to an adult car which I decided on being the 3G TL. I have used this site for years for issues with my TL and finally found a reason to create a post. I have a 2004 TL (Aspec) with the 6MT. I have invested way too many hours researching and have a few questions I can't find specific answers to. Rather, than beat my head against the wall of Google searching I decided to take a shot at creating a post. If there is one thing I have learned is that you can end up spending quite a large amount of money trial and erroring with the amount of J-Series build combinations. I have combined a list of questions that I think will help me and potentially others out in the long run.

BACKSTORY
My car is a 2004 TL Aspec w/Nav (if that matters). It has been and will continue to be my DD. I thoroughly enjoy this car and it has been thru quite a lot over the years. I am approaching 200K on the motor and realized I am at a crucial point if I want to keep it as my DD. I realized I probably need to do some major overhaul on the drivetrain if I want to keep this pumping for another 200K miles. That lead my down a giant rabbit hole. My first set of questions was the whole Gerzybear SC vs NA. Which after hours and hours of research led me to NA making more sense as my driving habits consists of lots of stop and go and A/C being a must. I wish i could make the SC feasible but where I am at currently just doesn't make sense.

CURRENT SITUATION
My current situation is as follows. I stumbled upon an amzing deal a while back the netted me another 2004 Aspec TL. I currently have a full spare of everything. J32A3 Motor, 6MT, Brembo Calipers, and ETC. My research of best NA build led me to the following. I know I will end up using an ecu from a 07-08 TL tuned and re-flashed via FlashPro and upgrading the pre-cat's, j pipe, and exhaust. I plan on either buying a J37A2(RL) or J35A8(RL) and mixing and matching parts with my J32A3 to get me the most performance with a budget. So, the questions I have I can't necessarily find all the specific answers to as there are so many different variations of each motor. My goal is essentially to get the most bang for my buck. Of the two routes which would be the most efficient / powerful.

• J32A3 / J35A8 blend
  1. J32A3 block with J35A8 crank/rods and J32A3 pistons or J32A3 block with J35A8 crank/rods and pistons (Google /AZINE search assumes the J32A3 is superior because of iron sleeves)
  2. J32A3 heads w/J35A8 cams or J35A8 heads w/J35A8 cams or J35A8 heads w/J32A3 cams?
  3. J35A8 IM & TB or J32A3 IM & TB or a mixture of the two?
  4. My theory on the best combo via lots of searching:
     1. J32A3 block w/J35A8 crank/rods w/J32A3 pistons
     2. Complete J35A8 head w/J35A8 cam
     3. Complete J35A8 IM & TB

• J32A3 / J37A2 blend
  1. J32A3 block with J37A2 crank/rods and J32A3 pistons
  2. EVERYTHING PAST THIS POINT I COULD NOT FIND CLEAR ENOUGH ANSWERS AND THAT IS WHAT LED ME HERE
  3. J32A3 heads w/J37A2 cams or J37A2 heads w/J32A3 cams or J32A3 head and cams or J37A2 head and cam
  4. J37A2 IM & TB or J32 A3 IM & TB or a mixture of the two. (Google / AZINE search led me to believe this could take quite a bit of modification
  5. My theory on the best combo via lots of searching:
     1. J32A3 block w/J37A2 rods/crank w/J32A3 pistons
     2. Complete J37A2 head with J37A2 cams (as they have the extra VTEC)
     3. Complete J37A2 IM & TB (I am currently unsure how difficult this would be to modify if at all possible

​​​​​​​CONCLUSION​​​​​​​

619rcr

Get a 07-09 j37a1 and either build a j36 using your existing block or install as is.

j37a2 heads are not a direct fit to j32a/j35a. However, those heads will bolt to the j35z non vcm (z3 or z6).

I've had a j37a2 in a 8th gen accord and built 2x j36s.One from a j37a1 and one from a j37a2. Both were easy. Just time consuming.

j35a8s are cheap and easy to find. But, not as stout as the j37a1. I actually passed up on a j35a8 at the junkyard yesterday.

Lastly, IM & TB 10-13 MDX, 09-14 TL SH AWD, ZDX are the most common upgrades. Although some people will bore out their stock IM and run an TB adapter. j35a8 IM and 07-09 MDX j37a1 IM & TB are not an upgrade other than possibly magnesium vs aluminum .

cmullins

Thank you so much for the knowledge and insight. I was under the impression that my model's 04-06 TL 6MT transmission would only bolt up to the J32A3 or J35A6. I would prefer the J37A1 but I didn't know it would bolt to the transmission. This is where my confusion started. I was unsure which block / piston / head combo would net me the most performance for a reasonable budget and still work with my transmission without a whole lot of trial and error. Most of my Google / AZINE searches didn't always specify which J35 / J37 parts were compatible. I knew there were so many different variations of each and without knowing which ones would bolt here or there I would really end up circling back and confusing myself. Thanks again for all the insight. I don't think the J37A1 is feasible because in my area the "junkyard" version is almost $2k, unless I am the ignorant one and this seems to be the standard going rate.

619rcr

My bad I saw j35a8 in the title and didn't think about the older style bellhousing of the j32a3. J37a1 crank and rods in the j32a3 block would be the way to go.

Car-part.com could help you locate a motor. I recently picked up a j37a1 for around $200 after $34 core exchange. Although, I had to pull it myself.

If you want to see an example of the j36 in an older block, I have a thread in the 2G area (skip to around post 45):
https://acurazine.com/forums/2g-cl-2001-2003-50/high-compression-j35a3-j32a2-rebuild-1005518/

cmullins

Thanks, after some more thorough digging around I can find a J37A1 for around $500 which seems reasonable. That now leads me to the next question, as for the top end do I keep all the J32A3 stuff or do I use the J37A1 or a mixture of both?

619rcr

If it was me, I would try to use the j37a1 heads. Reason being the intake port openings between lwr runners and cyl head are larger. Exhaust side is same as 3G.

Be aware that the 07-09 j37a1 crank is different than the 10-13. You wil need the 07-09. The 10-13 j37a1 intake manifold is bigger and will bolt to older j series lower runners.

You may have seen this thread:
https://acurazine.com/forums/3g-tl-performance-parts-modifications-112/j37a1-into-3g-engine-swap-notes-986666/

cmullins

That is good to know, it definitely helps me limit my search down to a smaller pool. I am assuming i would use the TB from the same 10-13 J37A1 as well?

619rcr

10-13 tb.

cmullins

When researching the j37 rods/crank I stumbled upon a post mentioning something about the length being different and potentially needing spacers. Can anyone confirm or deny this?

619rcr

Basically you want a matched set. i.e. j37 Crank with j37 rods. Some old posts incorrectly say to use j35 rods, those will be too long when paired with a j37 crank.

Piston size will match your block bore. Which if you do not overbore will be 89mm. Bear in mind that if you bores are excessively worn or tapered, this can cause problems down the road. I would recommend having a machine shop inspect and machine the block if necessary. I went with 89.5mm pistons on both my j36 builds.

cmullins

that is def good to know, I have put a lot of engines together over the years but I always started from good block with pistons and crank already in it. Sorry, I misspoke earlier when I was referring to the crank issue it wasn’t the rod to crank distance it was the flywheel/pilot bearing to crank distance. I couldn’t understand the problem but it involved a custom spacer for them to work.

619rcr

Yeah, that part is somewhat inconsistent and seems to vary depending on which crank, block and flywheel you use. On my j37a2 into j35z3 block setup, there are no spacers as the effective length is the same. The j35a8 from what I could tell when upgrading from j35a8 to j37a1 is the same effective length. The j32a3 is in the same generation. But, I've never owned or used a j32a3 block.

For older blocks from 2g cl/tl and 1g mdx, the old crank is definitely longer. Which, I ran into when first installing a j35a8 crank into a j32a2 block. I figured out a way to make the newer crank work. But, it's not necessarily a common setup.

cmullins

yeah I will try and find the link but it was a full build and he ended up putting two washers in as the spacers I think. I would just to get to that point and run into that. Definitely trying to figure it out on the front end vs the back end

cmullins

J36 build input needed please - AcuraZine - Acura Enthusiast Community

Hahaha, come to find out. You were the one commenting the fix on that. I was all in for a build but saw this and got scared. I had researched another build and it went smooth without a hitch but I think he was using J35 parts instead of J37. Its down below and very informative.

J36 build | Accord V6 Forum (v6performance.net)

619rcr

Yeah, used to run a j35a8 crank in a cl type s block. After several months started having issues engaging the starter. Long story short, even though the rear crank flange is approx 5mm shorter, I only had to add about a 1mm spacer. The same spacing worked when upgrading to j37a1 crank.

07-09 MDX is essentially in the same j series gen as the 7g accord and 3g TL. So, most likely you won't have a problem.

cmullins

That's good to know lol I just might try this undertaking.

cmullins

After further research my next question that I can't seem to find an answer for is will the J37A1 heads mate up to the J32A3? Research tells me the block has a bore of 89mm and the head has a cc of 90mm. I couldn't find a "for sure" other than a few posts that said they did it without an update down the road.

619rcr

Doubt you will find a definitive 'for sure' j37a1 heads will fit j32a3 block response.

You're also likely aware bore size is not necessarily the same as combustion chamber size. There is some thickness to the cylinder that surrounds the sleeve. The sleeve itself also can be overbored in .25mm increments commonly between 89-90mm.

Lastly, fwiw v6p had a thread where somone ran a j35 head on a j30a4 block. I beleive it was this link

cmullins

yeah, that’s one of the posts I read. It didn’t have any updates down the road. I also read about one where they bored the sleeves to 90mm and essentially turned the j32a3 into a j37. I was hoping to find a unicorn post of yeah I did it and works but I don’t think k so. I did watch some you tube videos of a guy comparing the heads and that’s where I noticed the 1mm difference in the combustion chamber diameter. In the grand scheme that would only make it .5mm to big all the way around which equates to about 1/64th. May just trial and error especially since the j30 is even smaller.