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HybridZ

My official L31DETT RHD thread.


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It is my understanding that large bores on the L6 blocks is best left to those of us that love NA and the turbo boys should limit the bore to 88mm and not go any larger due to the issues 1 Fast Z has found with his turbo 89mm DOHC 3.1 build.

 

This was known well before this time in Japan...

 

Actually for mild turbo applications you can bore larger, but the specific output isn't really all that great. When you start pushing 200+HP/Liter, bore wall stability is a good thing.

 

How thick are the liners on an Oldsmobile DCRE making 1800HP from 7Liters? (Or thereabouts...) This isn't rocket science, you just need to know where to look.

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Ok, so look here for updates every couple days As Ill just keep adding to this thread for my updates of my progress on the L31DETT RHD car. I got the intercooler installed, as well as the alluminum r

There is ALOT of cost in time that has gone into this project. Over 500 Man hours Between my father and I for sure. We have been doing LOTS of calculations, trial and error, quality controll, etc.

Actually for mild turbo applications you can bore larger, but the specific output isn't really all that great. When you start pushing 200+HP/Liter, bore wall stability is a good thing.

 

I'm actually banking on that statement.:mrgreen: Dave Rebello pretty much told me the same thing when I expressed concern about boring out my block to 89mm. I think the difference here is I'm looking to get "only" 450ish whp out of mine where 1 fast z is pushing out considerably more.

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Yea its coming. I sourced a couple sets of 240 rods, as with the z32 pistons, the Compression distance is shorter. Even though it is only going to be .040" overbore, I am still sonic testing the block and going to offset bore the block to maintain maximum bore thickness according to core shift of the mold. The new thrust bearing design is also time consuming. It is being incorperated right in front of where the flywheel bolts. I never liked how the thrust of a crankshaft is taken up in the center main. WHen you push thousands of pounds of pressure on a flywheel, you are trying to compress the back three cylinders on the crank, before the pressure gets to the center main. With my new design the crankshaft will basicly not see any front to back force, and therefore, relieving stress on the crankshaft also.

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Yea its coming. I sourced a couple sets of 240 rods, as with the z32 pistons, the Compression distance is shorter. Even though it is only going to be .040" overbore, I am still sonic testing the block and going to offset bore the block to maintain maximum bore thickness according to core shift of the mold. The new thrust bearing design is also time consuming. It is being incorperated right in front of where the flywheel bolts. I never liked how the thrust of a crankshaft is taken up in the center main. WHen you push thousands of pounds of pressure on a flywheel, you are trying to compress the back three cylinders on the crank, before the pressure gets to the center main. With my new design the crankshaft will basicly not see any front to back force, and therefore, relieving stress on the crankshaft also.

 

I always thought the thrust bearing in the center allowed the load to be taken off the rear cylinder to reduce the wobble effect at high RPM that you would induce in an inline 6 if you were to slow down the rear-most cylinder/main and let front-most cylinder/main exert more rotational force at the opposite end of the crank...

 

Just playing the devils advocate here. What's the reason? Did it fail on you before? Because I believe the RB engine platform was designed this way because it proved to be successful in distributing vibration/torsion throughout the crankshaft.

 

I really don't think the center main is as much of an issue as the vibration is. Are the 2JZ's thrust washers not situated on the center main as well?

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Not trying to take away anything from the work that you have done, i just happened to flip though a magazine today and saw a pick of a dohc l28 head made by osgiken. I guess the magazine was little behind the times as its older news, but cool no the less.

 

http://community.ratsun.net/topic/23916-dohc-os-giken/

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