J35 NA Build Plans - Input Appreciated

[IDon'tKnow]

As a basis to understand my thoughts: I'm building a J35 to go into an AW11 MR2. It's light and with a 3.5 going in it, I'm obviously concerned about traction and am hoping to move the torque curve up quite a bit. I've got a J32A2 and a J35A4 already and am going to be combining the two to hopefully make a +300whp NA monster.

My thoughts / questions I would like to confirm and have answered before I get in too far over my head:

I understand that redline for the J32 is 7200rpms. With the J32's 86mm stroke, this puts piston speed at 67.71 feet per second. To turn 7200 with the A4 crank, the piston speed will be 73.23 fps. I'm trying to decide what redline to build for and there are a few considerations that will affect this. I'm hoping though that I will be able to run it up to 81.36 fps (8,000rpm) with shot peened factory rods and ARP rod bolts but am unsure as that is a very high number.
What RPM level is the valvetrain good for before running into valve float?
What is the limiting factor for flow above 6.5k? I've heard a few places that the J starts to taper off at that point and would like to know if it's a cam issue, a head issue, or if it's IM and EM restriction?
The 05+ RL pistons and the 07+ Type-S pistons are the only factory forged pistons available, and the dome on both is a little bigger than the J32A2 pistons? Anyone have any idea about the weight differences between these and the cast pistons?
I read somewhere about factory forged one piece rods having their bearing ends split before being machined but am at a loss the find the information again. Any direction here guys – what platforms where they used in?
Does anyone feel that using the A4's cast crank would compromise the strength of the bottom end? I saw a forged 93mm stroke crank on eBay for $260, but am not sure that it's worth bothering with.
What type of cylinder liner is is used in the J32 block? I know that it is designed to dissipate heat better than the A4 block but am curious as to how it does so. I'm trying to decide whether to just put a fresh hone on the bore or take it up a bit.
Are the IM's the same on the J35A4 & J32A2? I know the 35 has the spacer, but any other differences?

Modification plans are:
Micropolish, MILD Knife Edge, and Balance J35A4 Crank in J32 Block
Add ARP Rod Bolts to J35A4 Rods and Shot peen them
RL Pistons
J32 Heads
Outlaw Engineering IM Gaskets
Port and Polish IM and Remove Butterflies
Port Match IM and DC Headers to Heads
2.5” or 2.75” True Dual Exhaust with X-Pipe
Custom Machined 1.25” or 1.75” Plenum Spacer
Type-S TB Bored to 71mm, matched to IM
Standalone EMS – (Megasquirt – I know; quite a challenge, but I'm confident that I can get it worked out)

Possible modifications I'm not sure about:
-Shave Cylinder head
-Custom Adjustable Cam Gears
-Run Ethanol

I bought those motors a few days ago on a whim/ advise of a friend before I did any research on J-motors. Thanks in advance for any input guys.

[paton]

Sounds like an amazing project. For someone who didn't research the J engine prior to making a purchase, you have moved quickly and learned a lot!

I believe there is a factory forged crank for your application. I thought it was the Odyssey crank but I could be wrong. If that was the case than you already have one.

This will be a great project. When do you plan to get started with the car? Post some pics of that MR2.

[teh CL]

if you want a factory forged crank go with one out of an 01' MDX..

[wolydotmatrix]

X2 on the forged cranks. 300 should be poissible w/o many mods when using 35 crank/rod/ piston w/32 heads (port-work) better cam shaft and the right tune.

[wolydotmatrix]

Oh yeah, welcome to the site.

[IDon'tKnow]

I'll start a build thread and get pictures going in the next few days. I'm not in the best shape financially right now so things won't be moving along too quickly, but much of the work requires labor and little cash so you will see some action. I'll be using one of the motors to mock everything up in my parts car before I dig into my daily driver. Trouble is I need to get my hands on a 6MT too.

Apparently there is some confusion regarding the crankshaft and rod material used in the odyssey motors. Most references I've found say that the rods and crank are both cast parts, but according to URL="http://corporate.honda.com/press/article.aspx?id=20010221001326"]Honda's corporate website[/URL]: To further save weight and minimize vibration, the forged-steel connecting rods are a compact, lightweight type, measuring only 19 mm in width. Even the connecting-rod bolts are a lightweight, small-diameter, nutless type. However, despite their smaller size, they have the same strength margins as larger, conventional nut- and threaded bolt-type fasteners, because they are designed to be torqued to the higher clamping forces of the bolt material's plastic-deforma-tion region, instead of its lower elastic region.

The engine's fully counterweighted, forged-steel crankshaft has also been kept short in order to minimize vibra-tion and uses a special dual-mode crankshaft damper pulley.

Perhaps you can't always trust Wiki, or perhaps Honda was telling a lie. I really would like to get to the bottom of this. EDIT: The Honda material is for a 2001 Odyssey.... disappointed that Honda downgraded materials.

I'm also reading that the RL and 03+ TL Type-S Pistons are both forged, but there was no Type-S between 04 and 07..... If the 03 pistons are forged, I would expect the 02 pistons to be also since it's the exact same engine code. If I get the motor apart and find that the pistons are in fact forged, I will probably just stick with those. They don't yield as high of a compression ratio (10.5:1 instead of 11.1:1) but I will do a mock assembly, clay the motor, cc the heads, and then have the machine shop mill the head for half the cost of the RL pistons.

I'm really excited about this project but the seemingly contradictory information I'm finding in various forums has me thinking that I'm going to have to take everything I'm hearing with a grain of salt.

Wolydotmatrix: When you say better cams you are you referring to the Type-S cams or custom grinds? Do you have reason to believe there isn't enough cam for the 7k-8k range?

RPM Systems: I'll definitely be looking for help to get a base map. I was already planning on ordering from DIY, I've heard nothing but good things about them.

[wolydotmatrix]

I believe the 05 TLS cams from what I have heard have the better lift and duration for better HP. I know your looking for facts on this matter, but this again this is second hand information. Hytech makes a valve spring upgrade talk to devinemotorsports. I don't believe there is a good aftermrket optoin for cams at this time. I don't do regrinds for relability reasons. Search Acurazine and V6performance.net for other possibilities as far as cam shafts, crank, rod and piston composition. These are things they leave out at the training center.

hope this helps

Adam

[acidbath124]

i have heard that p2r does some kind of regrind and headwork and that bisimoto does aswell but i dont know for sure

[stillhere153]

saw this on another forum belongs here also
http://www.honda-performance.com/search2.asp?zoom_query=v6

[IDon'tKnow]

saw this on another forum belongs here also
http://www.honda-performance.com/search2.asp?zoom_query=v6
Thanks for that link. Good to see some off-the-shelf valvetrain parts.

I'm not sure though that they are of much use on a 3.5 with stock cams considering the piston speed restrictions with a 93mm stroke. Perhaps they would be necessary with a bigger cam. If they are just stiffer to prevent float at high RPMs and not capable of higher lift, they would be useful on a J32A but not at all - even with longer duration cams - on a J35.

I've noticed on a few other forums that most engine builders have gone with the RL pistons (11:1 with a 93mm stroke) instead of the Type-S pistons (10.5:1 with an 86mm stroke) - I don't know the volume of the chamber on the head so the calculation isn't exact, but the TL-S pistons should yield a higher compression ratio / have a larger dome.

________________________________________
3,200cc / 6cyl. = 533.33cc's per cylinder
3,500cc / 6cyl. = 583.33cc's per cylinder
________________________________________
Displacement divided by compression ratio gives ~chamber volume at TDC in J32A2 & J35A3

533.33cc / 10.5 = 50.79cc chamber volume at TDC
583.33cc / 11 = 53.03cc chamber volume at TDC
________________________________________
J35 Displacement with J32 Chamber Volume give ~ Compression ratio of TL-S Pistons in 3.5 application:

583.33cc / 50.79cc Chamber Volume = 11.49:1 Compression Ratio

This makes me wonder why the TL-S pistons aren't more commonly used. Perhaps I just haven't read up enough on different builds.

And just to correct what was stated is a previous post, it seems that all of the TL-S pistons are forged like the RL and 07+ pistons.

I'm going to try and move the motors from a storage unit to my store tomorrow or early next week and get started on tear down.

[SonicRacing1]

well good luck with the build. i'll be looking at this thread as it progresses

[acidbath124]

r you talking about putting the cl-s heads on the j35 block ? if so from what i understand people use the RL pistons for valve clearance

[IDon'tKnow]

r you talking about putting the cl-s heads on the j35 block ? if so from what i understand people use the RL pistons for valve clearance

I'm going to swap the Odyssey crank and rods into the J32A2. The orientation of the piston in the bore @ TDC doesn't change between the two motors so the valve clearance shouldn't be altered at all. All of the increase in compression ratio comes as a result of the increase in displacement; the chamber volume at TDC stays the same.

I'm going to clay the mocked up motor and cc the heads before I before I make a final decision about modifications. I'm leaning toward bumping the compression up even higher if I can gather the extra funds to fabricate adjustable cam gears and ceramic coat the chambers, pistons, and exhaust.

[hondaboy4life]

You look into trying to use the 3.7 crank, rods, pistons etc? Word of mouth is its doable with some machining.

[IDon'tKnow]

You look into trying to use the 3.7 crank, rods, pistons etc? Word of mouth is its doable with some machining.

I didn't look into it in depth. If I were building a motor for a TL or an Accord I would be more interested in the possibility, but I think the torque I'm going to get out of a 3.5 is going to be difficult to put to the ground in a 2,200lb. chassis to begin with.

The extra 3mm of stroke wouldn't be a huge hinderance in terms of revability, but I'd feel better about reving to 7,800 rpm with the 93mm crank.

Also, I'm trying to keep everything on as tight a budget as possible. I'm considering selling the J35A4 or trading it for a J35A1 just to be sure I get the forged crank and rods. Some folks say that the A4 has the same bottom end as the A1, but I can't be sure and I'm not sure I want to pull apart a perfectly good engine to find out. Honda says that the part numbers are the same, but that's from their part replacement database - doesn't guarantee that they were the same from the factory.

Wikipedia says that the A4 has a cast crank but they don't cite any references. As stated above I found a press release that states the A1 has forged rods and crank - I can imagine though that Honda might have chopped the production budget on the A4 and went with cheaper cast parts. Still I wish someone would give me a good concrete reference so I could settle the question once and for all.

I think I can find a J35A1 Longblock for ~$200, so I might just go that route and sell the A4 I already have.

[StolenLegacy]

Thanks for all the info!!!! Please please please let me know if u find out which j35 has forged intervals. I found 2 j35a4's and I'd love to know before I decide to buy one. You have definatly done your research. Thanks for ur help.