Torque Plate for Datsun L28

[raremotive]

Anyone know where I can find a torque plate for a L28?

Thanks.

[evildky]

I know a guy that made his own out of an old cylinder head, you plannning a large overbore?

[raremotive]

from 86 mm to a new 86.5 mm... not much really..

Because I am not speaking for L-series.. but RB.. L28 have large enough bore and same cylinder pattern.
Modified by Rare_f8 at 10:40 PM 11/4/2008

[evildky]

ah, yeha I know the head bolt pattern, cylinder spacing etc was the same but wht the trque plate for such a minor overbore? I thought the rb was a stout block?

and I am sure you can find a used L head for a heck of a lot cheaper than an rb head if you wanted to make your own

[raremotive]

interesting suggestion. Every little bit helps. Just a picky intuition I have.

[evildky]

FWIW, I'm boring out my L28 .10 over and not torque plating it

[raremotive]

Yeah if, I had an L28 I would too. But for me the high hp, boost and rpms. I just rather have the knowledge of a proper toleranced block, not assumed. Every little bit helps.

[evildky]

how high HP we talking? my "L30" should put north of 450 whp

nothing wrong with being over cautious, I know when dealing with the honda motors torque plating is a must as they flex too much, but the L and I assume the RB are stout enough to take it

[raremotive]

700 minimum, 10k rpm, boost.. unknown.. at this point.

Honda's has aluminum blocks which makes them so ductile.

However even "stout" cast iron flex a tiny bit.

Ideally would be to run heated oil to get the block expanded to operation temperatures and with a torque plate bore and hone.

But torque plate is enough for me.

[Stealth-Z]

The torque plate idea floated around my mind for a long time. Finally I wanted to see for myself. I had this torque plate made for the final honing of my RB30 block. It was bored to 86.5mm. With the ARP head studs torqued down, we could see the block distortion at the stud locations.

[evildky]

700 hp is a lot, and of course you boost levels to achiev that goal will be dictated by your choice of turbo(s) what turbo(s) are yu planning on running

[raremotive]

700 hp is a lot, and of course you boost levels to achiev that goal will be dictated by your choice of turbo(s) what turbo(s) are yu planning on running

It's unknown due to a undecided turbo set. It will be determined sometime in the future when it's time for it.

Or in other words. I have a open list for twins. But right now I am working on the frame and setting the block up for it's build. Then I will be able truly sit down and decide which one will be up to the task.
Modified by Rare_f8 at 10:42 PM 11/5/2008

[raremotive]

The torque plate idea floated around my mind for a long time. Finally I wanted to see for myself. I had this torque plate made for the final honing of my RB30 block. It was bored to 86.5mm. With the ARP head studs torqued down, we could see the block distortion at the stud locations.

Glad you were able to see some elastic deformation the cast iron really undertakes.

It's hard for me to make a torque plate all just for one time use.

[minnesotazcar]

i have to agree for such a minor overbore i dont really see why a torque plate would be that nesessary espesially if your not going to have much use for it after that

[Stealth-Z]

Glad you were able to see some elastic deformation the cast iron really undertakes.

It's hard for me to make a torque plate all just for one time use.

Hopefully it will get more than one use. The person who will be doing the tuning on my motor wants to get in to building RB25's & RB26's. He has built quite a few high horse power Z32 Twin Turbo V6's.

[74260zt]

I had one made for myself also. The only thing I'd really really be carefull of, is over bore. I wouldn't go over 1mm....

[raremotive]

yeah I know. I really don't want to get any larger than 86.5

[raremotive]

The torque plate idea floated around my mind for a long time. Finally I wanted to see for myself. I had this torque plate made for the final honing of my RB30 block. It was bored to 86.5mm. With the ARP head studs torqued down, we could see the block distortion at the stud locations.

I didn't notice it before, but that's a rb30 block.

How much did you pay for the torque plate?

[Stealth-Z]

$500

[raremotive]

Hmm, is there some way I can get a copy of a blueprint for that torque plate?

[Stealth-Z]

He used my block and head to make it. I will ask him after the holiday if he has a blue print for it.

[raremotive]

Cool thanks.

[raremotive]

Bump. Ever ask him?

[Stealth-Z]

Sorry, forgot about this. Will ask tomorrow.

[evildky]

you can use a HG for a template, the RB and L6 actually can interchange torque plates

[raremotive]

Yes, good idea. I was just thinking blue prints and a billet.. and bounce around some machine shops or ask a friend to hook me up with his machinist friend.

Here's another example, of why I rather have a clear conscience: Done on a VG30DE Block

The block wasn't actually bored but honed oversized, reducing costs. He used the deck plate I supplied, with interesting result. He honed the bore to 87.50mm as the correct clearance for the 87.43mm JE pistons was 0.07mm. After honing he noticed the bore stretched 0.02mm (to 87.52mm) which in turn means that the head bolts literally pull the bore together reducing bore size by 0.02mm. If the bore was honed without the deck plate, the clearence would have been way less increasing the chance of a wrecked piston (ring).

[Stealth-Z]

Sorry, no blue prints. He used the block, head and gasket for measurements then made it.

[raremotive]

Hmm, ok. Thank you.