[Grand_hustle17]

Hey random question... I know and read about j series heads but have anyone ever tested a real life power difference between say a j30/32 and j35 or j37 head?... Ive read about the flow and all the theories and i know for the most part once you are that far into the engine other things change too but other than telling me one "flows better" whats the pros and cons of these.. Realistic power.. Not theoretic boring stuff lmao.. Sorry fort he ignorance lol.. Thinking of grabbing some J35 heads? Hoping for a tq bump

 

[NVA-AV6]

The only real way to get a sizable tourqe bump is increasing the stroke of the engine....

 

[Grand_hustle17]

So going from a j32 to j35 head wont necessarily help.. R will it seeing as though im incrasing volume size?

 

[thisaznboi88]

get a smaller j30 head to bump static compression just like the EJ 25 guys. They use the smaller EJ20 heads

 

[Sonin Fury]

Im about to start a thread for putting the J37A1 heads on a J30A4.


Thank you very much for the info NVA-AV6 and Sonnick.

The car is missing out right now, so I cannot do a before dyno, but I am sure there must be some stock dynos we can use to compare against, after I have the swap done.

 

[Grand_hustle17]

Riiight... Noone has a before and after?

 

[thisaznboi88]

Go dyno then. ;p

 

[Sonin Fury]

Just to be lazy, because I know I have already read it, is it the 11 MDX that the dual VTEC?

Reading the thread on Acurazine by justnspace, he put the J37A1 heads on with the stock ECU I think?

I am assuming using the newer heads with the Dual VTEC would mean a different ECU is required?


I am really interested in this because if all goes well with this swap on the J30 I am trying to figure out the best OEM combination of J, that doesnt require cracking open the bottom end, for my J Swap EK project.

 

[accord325]

J37a1 heads on a J30 block has been done (yawn).

LMAO, I joke. Interested to see the outcome!

 

[Sonin Fury]

Posted these questions on Acurazine as well......


#1
Use the J32 or J37 timing belt?

#2
Looks like the OP who did the J32/J37 heads is still on the factory ECU? Is that doable with the Accord as well?

#3
Still trying to figure out exhaust. Sonnick said the Gen 8 Accord. I hate to double guess him after how helpful he has been, but RV6s precats list compatibility (on the same unit) for 03+ MDX and 7th Gen Accord, while the 8th Gen Accord is in fact a different unit.



Also my buddy just got his tax check dont know how much, but apparently there maybe a full exhaust on this build.

I am assuming there are plenty of examples of what kinda of power full bolt on J30s make, so I think it will be interesting to see that scenario with the 3.7 heads yeilds.


Also I apologize if I have upset anyone jumping in everyone elses threads, but as soon as we have all the parts on hand, I am going to do a complete round of pictures on everything, and hopefully a nice write up with pictures as my contribution for to the forum for all the help.


Payment for heads should be sent tonight, going up to a yard to get the injector bases/runners from an 8th Gen accord.

 

[accord325]

#1 - EITHER. I posted this answer to the same question you posted in another thread

#2 - not familiar with OP's Build

#3 - you need 8th Gen PCD's for the 10'+ MDX heads.

 

[yungone501]

Just to be lazy, because I know I have already read it, is it the 11 MDX that the dual VTEC?

Reading the thread on Acurazine by justnspace, he put the J37A1 heads on with the stock ECU I think?

I am assuming using the newer heads with the Dual VTEC would mean a different ECU is required?


I am really interested in this because if all goes well with this swap on the J30 I am trying to figure out the best OEM combination of J, that doesnt require cracking open the bottom end, for my J Swap EK project.

The MDX was never given dual VTEC heads. ONLY 09+ RL and TL 3.7's with the engine codes j37a2 and the j37a4 (respectfully) have the added exhaust VTEC feature. The 07-13 MDX 3.7 had two variations of the j37a1. The 07-09 j37a1 has heads/cams similar to the 3G TLS but with a newer and improved intake port design as well as valve designs that was said by Acura themselves to add 14hp alone to the engine compared to the previous 3.5 heads. So with that, its safe to assume they flow better. In the years 10-13, the j37a1 head was redesigned (though it will still fit 03+ Honda j-series blocks) and given a simplified camshaft and valvetrain. The 10-13 heads also were given different exhaust port designs. These cams will NOT fit any prior years and are exclusive to this head design which the Accord also began to carry beginning in 08 with the j35z engines.

Also, the dual VTEC setup is ran exactly the same way as the older systems electrically speaking. No changes in wiring or ECM are required.

The biggest concern with running j37 (or any 89mm+ sized heads) heads on the j30's is the combustion chamber diameter and its possible issues brought about when being mated to an 86mm bore. I've read of one j35a8 head swap onto a j30 but never seen long term updates and remember him having issues with coolant temps if I remember correctly which I feel is completely unrelated to the bore/chamber diameter differences.

 

[jiga21]

^But if u have a j32 bottom end already intact & need heads well dual VTEC sounds sinister with supporting boltons, fuel, flashpro & cheap aggressive Dyno Tuner

 

[thisaznboi88]

ugh.. I have a J30a5 with a J35a8 head on my car. Been on it for 8 months now. No issue with coolant getting up to temp (its been 25 degree and lower with snow here).

The MDX was never given dual VTEC heads. ONLY 09+ RL and TL 3.7's with the engine codes j37a2 and the j37a4 (respectfully) have the added exhaust VTEC feature. The 07-13 MDX 3.7 had two variations of the j37a1. The 07-09 j37a1 has heads/cams similar to the 3G TLS but with a newer and improved intake port design as well as valve designs that was said by Acura themselves to add 14hp alone to the engine compared to the previous 3.5 heads. So with that, its safe to assume they flow better. In the years 10-13, the j37a1 head was redesigned (though it will still fit 03+ Honda j-series blocks) and given a simplified camshaft and valvetrain. The 10-13 heads also were given different exhaust port designs. These cams will NOT fit any prior years and are exclusive to this head design which the Accord also began to carry beginning in 08 with the j35z engines.

Also, the dual VTEC setup is ran exactly the same way as the older systems electrically speaking. No changes in wiring or ECM are required.

The biggest concern with running j37 (or any 89mm+ sized heads) heads on the j30's is the combustion chamber diameter and its possible issues brought about when being mated to an 86mm bore. I've read of one j35a8 head swap onto a j30 but never seen long term updates and remember him having issues with coolant temps if I remember correctly which I feel is completely unrelated to the bore/chamber diameter differences.

 

[Sonnick]

I'm really excited to see how these 2G J37 heads perform. With the more aggressive cams, better valvetrain & port flow, I think there could be some good gains.

 

[accord325]

I have J37a1 heads on my J30 and no warm up issues, but I also live in FL. I just put down 267/225 on a 150k short block that has seen 8 bottle of nitrous. I am also only on my 10th Cal. with Dom, and anyone tuning with him knows there are a lot more before the tune is complete, so more power to be made.

 

[Sonin Fury]

#1 - EITHER. I posted this answer to the same question you posted in another thread

#2 - not familiar with OP's Build

#3 - you need 8th Gen PCD's for the 10'+ MDX heads.

Thanks. Sorry dont mean to doubt you but I always like to confirm with multiple sources.

The MDX was never given dual VTEC heads. ONLY 09+ RL and TL 3.7's with the engine codes j37a2 and the j37a4 (respectfully) have the added exhaust VTEC feature. The 07-13 MDX 3.7 had two variations of the j37a1. The 07-09 j37a1 has heads/cams similar to the 3G TLS but with a newer and improved intake port design as well as valve designs that was said by Acura themselves to add 14hp alone to the engine compared to the previous 3.5 heads. So with that, its safe to assume they flow better. In the years 10-13, the j37a1 head was redesigned (though it will still fit 03+ Honda j-series blocks) and given a simplified camshaft and valvetrain. The 10-13 heads also were given different exhaust port designs. These cams will NOT fit any prior years and are exclusive to this head design which the Accord also began to carry beginning in 08 with the j35z engines.

Also, the dual VTEC setup is ran exactly the same way as the older systems electrically speaking. No changes in wiring or ECM are required.

The biggest concern with running j37 (or any 89mm+ sized heads) heads on the j30's is the combustion chamber diameter and its possible issues brought about when being mated to an 86mm bore. I've read of one j35a8 head swap onto a j30 but never seen long term updates and remember him having issues with coolant temps if I remember correctly which I feel is completely unrelated to the bore/chamber diameter differences.

Thank you for this.

^But if u have a j32 bottom end already intact & need heads well dual VTEC sounds sinister with supporting boltons, fuel, flashpro & cheap aggressive Dyno Tuner

I have a 60k mi J32A2 sitting on a stand. I am kind of using my buddys accord as a test to see if I want to do the straight J32A2 swap or some type of Hybrid build swap.


I have another buddy with a J32A2, TLS Intake manifold/Blox 80mm, custom headers, running AEM EMS in an EG coupe and I believe he dyno'd real short 280s HPwise.

 

[brian6speed]

If you already have a j32a2, I would suggest just keeping internals stock for the time being. Spend your money on the intake and exhaust.

Bored tb, ported IM, plenums or plenum spacers, ported runners, custom long tube headers, light weight pulley or flywheel. SHAWD IM is another option. On the j32a2 you can bolt up a 76 MM b series tb.

Those mods can be good for 280whp & 245 wtq untuned.

If you tune on EMS standalone you can see up to 300 whp & 270 wtq.

 

[accord325]

Thanks. Sorry dont mean to doubt you but I always like to confirm with multiple sources.





Thank you for this.





I have a 60k mi J32A2 sitting on a stand. I am kind of using my buddys accord as a test to see if I want to do the straight J32A2 swap or some type of Hybrid build swap.


I have another buddy with a J32A2, TLS Intake manifold/Blox 80mm, custom headers, running AEM EMS in an EG coupe and I believe he dyno'd real short 280s HPwise.

What vehicle do you plan to install this J32a2 into, hope it's DBW

 

[Sonnick]

If you already have a j32a2, I would suggest just keeping internals stock for the time being. Spend your money on the intake and exhaust.

Bored tb, ported IM, plenums or plenum spacers, ported runners, custom long tube headers, light weight pulley or flywheel. SHAWD IM is another option. On the j32a2 you can bolt up a 76 MM b series tb.

Those mods can be good for 280whp & 245 wtq untuned.

If you tune on EMS standalone you can see up to 300 whp & 270 wtq.

You are really stuck on that 270wtq number...I've never seen a J32 make near that torque with the 1 exception of P2Rs motor, who's mods are still controversial to date. *Most* J32s make ~24x and I can guarantee will not gain 25wtq with a tune. Most J35s/36s make 260-27x wtq.