[nighthawk04v6]

So you think I'm flowing to much air. I thought the same thing intially but want to know if the over lap on the heads is hurting performance. With your theory I only have to get $1200 (cams and valve train) in parts .

only 1200? A few hundred more You could get a complete j35a8 long block, make 300 whp, 270-280 ftlb with out tinkering with a thing. Just saying.

 

[pa1nt13aller]

Are you sure your TLS heads combustion chamber is 86mm? J35's have 89mm pistons and 93mm stroke.

Ya the J32a3 and J35a8 have a 89mm combustion chamber.

 

[thisaznboi88]

Ask the OP to measure the heads and you measure your heads. Its either 86 or 89 for both or they are totally different. Save you guys all the guess work. I wish yungone was on here. He has all kind of heads

 

[accord325]

only 1200? A few hundred more You could get a complete j35a8 long block, make 300 whp, 270-280 ftlb with out tinkering with a thing. Just saying.

Wouldn't the bell housing have to switched out for the J35a8? I haven't priced it out but figure that would be another $400-$500, yes ?

I plan to use a J35a5 but an a8 would be sweeett

 

[accord325]

Ask the OP to measure the heads and you measure your heads. Its either 86 or 89 for both or they are totally different. Save you guys all the guess work. I wish yungone was on here. He has all kind of heads

J30 = 86mm
J32 = 89mm
J35 = 89mm
J37 = 90mm

Still want to hear what the over hang will do. Cant find info on it anywhere.

 

[Ilovemyvtx]

36.3mm Mid Lobe Total height - 30mm base circle = 6.3mm

6.3 x 1.6 (rocker ratio) = 10.08, what the hell is the 25.4 ?

(8mm x 1.5)/25.4=0.472in

It's to convert it to inches. 25.4mm = inch. Our rocker ratio is 1.5:1. So (6.3mmx1.5)/25.4=0.372in max lift.

 

[nighthawk04v6]

So you think I'm flowing to much air. I thought the same thing intially but want to know if the over lap on the heads is hurting performance. With your theory I only have to get $1200 (cams and valve train) in parts .

Wouldn't the bell housing have to switched out for the J35a8? I haven't priced it out but figure that would be another $400-$500, yes ?

I plan to use a J35a5 but an a8 would be sweeett

bellhousing is the least of your worries. its a better motor all around compared to the rest IMO. it's better to spend the money than to play the guessing game spending money.

 

[thisaznboi88]

^ need to start saving up for this badboy

 

[accord325]

bellhousing is the least of your worries. its a better motor all around compared to the rest IMO. it's better to spend the money than to play the guessing game spending money.

So its a straight swap with the bell housing ? Could have swore there was something else that needed to be done to make it work.

 

[accord325]

It's to convert it to inches. 25.4mm = inch. Our rocker ratio is 1.5:1. So (6.3mmx1.5)/25.4=0.372in max lift.

So our heads flow 270ish CFM stock, pretty good

 

[simione]

Ask the OP to measure the heads and you measure your heads. Its either 86 or 89 for both or they are totally different. Save you guys all the guess work. I wish yungone was on here. He has all kind of heads

I emailed and pmed Robert to chime in. I guess he is too busy

 

[thisaznboi88]

I left a message on his post on acurazine

 

[thisaznboi88]

Robert answered me. its all the same ****


As for the question on the j37 heads compared to the smaller liter j-series heads, I'm assuming this is coming from the debate over on V6P right? Sonnick (Bryan) asked me to comment on the thread and have simply forgotten. I'll answer this one question and end the debate by saying this one thing: Honda used the exact same heads between the 10+ MDX 3.7 as well as the 08+ Accord 3.5 (and nearly every other motor they built). They are the same notorious R70 castings that are used on the HPD HR28TT and HR35TT engines.

89mm k-series pistons and J32/j35 compatibility - AcuraZine Community


and here is what an HR28TT looks like

http://blog.hpd.honda.com/2011/06/hpds-new-v-6-ready-for-le-mans.html#.VBY4Yy5dXVs

 

[accord325]

^ much appreciated but it didnt touch on the sole question. What happens with the overlap from a large combustion chamber then the piston size. He says not to use a smaller piston.

I asked him on AZ

What happens if the heads Dome side (J37 90mm CC heads) overlap on a J30 (J30 86mm pistons) ? I would assume the overhang in the combustion chamber is not improving power. That is the main question on V6P.

 

[thisaznboi88]

^ sorry totally missed that point. lol
well if all the heads chamber diameter are all the same then its going to be the same as stock. This is assuming all the CC is the same.

If the CC in the head chamber is larger 89mm vs 86 than you probably lose Compression would be my guess since you have more area for the air to move around and be less compressed (sorry I can't word this correctly, I'm studying diabetes right now)

 

[accord325]

^ no worries. The Piston size I listed in an earlier post are usually matched up with the CC in their heads.

I had the J37 heads measured and they are indeed 90mm, our pistons are 86mm. My question is rhetorical, but I would rather hear it validated by Youngone

 

[accord325]

I dont think a J37 head on a J32,J35 (89mm) would make much difference, only .5mm overhang, but on a J30 it's 2mm all around.

244whp, 204wtq = DTB IM, CBE, LWP
260whp, 210wtq = DTB IM, CBE, PCD's, UD LWP, RDX injectors, J37 heads (decked, ported, valve job)

 

[qaz393]

Is the j35a8 block better than the j32a3 assuming they have the same internals and head?

 

[oraclem19]

j35 is of course going to have that extra .3L compared to the j32.

As far as this overhang issue, anyone want to do some quick geometry calculations and figure out just how much this overhang adds? Like say someone with a spare head laying around that can measure just how deep the area is between the deck and the CC area of the head?

 

[thisaznboi88]

Is the j35a8 block better than the j32a3 assuming they have the same internals and head?

I believe the sleeve are the same and if your moving everything over from a j35a8 into a j32a3 I don't see why not minus the oil squirter.

But after all that work I would have Just bought a j35a8 and a matching tranny for the added benefit of Lsd. Just because you have to crack open the old tranney and replace the bell housing and possibly get an Lsd to add on.

I'm pretty sure you can get a j35a8 and a tranney for cheaper than a j36/37 build and have less down time waiting for parts from Honda. (not hating on anyone that has a j36/37, more props to you guys for thinking out of the box). From what I been reading on acurazine it's a ***** to get perfect bearing for the the crank.


Now back to the OP thread. How's everything looking?