boring a vg30 out to vg33 will Not work

Thanks for the info. I am still interesting in punching out the block, and just wanted to make sure y'all didnt have a wall failure.

[quote]raracing1 wrote: [quote=ZFast88Z]

Originally posted by raracing1

HI I do not have all the time of the world but why do you just start with a vg33 long block it`s heaven!
That's exactly what I started with. I then bored it out to 97.5mm making for a VG37ETT.
VG33 is all ready on the boring edge of the main cap support I deffinitively don`t recomend to go further than .020 or let your crank go away! I mean it

so i take it raracing was correct?

Grr,

That is one possible explanation yes. We will see what happens with this new block. If the same results occur, then I would agree that it is due to the decrease in block strength due to removing to much material.

I believe there are ways it could be fixed, but I dont think any one them is a decent or viable option. Ive thought about machining a billet replacement crank girdle, but at the time when the idea was discussed over dinner, it didnt seem like we were going to have these issues.

With the Z32 block somewhere around 500 WHP seems to be the limit if reasonable durability is required, the crank starts walking around then even with ARP studs. As most of you would know Nismo made a replacement crank girdle for the Z32 and the Electramotive single cam VG's had something similar. But then you are getting into dry sump territory it seems to me, a stock sump pan could not be used over a full girdle.

Basically the VG's block skirt is not deep enough to allow the bolting on of a simple flat plate brace over the top of the stock girdle.

Thinking about this a bit more, perhaps it may be possible to keep the stock girdle and make up some tabs that would go from the main bearing cap area across the block webs towards the sump pan sealing area. Correct me if I'm wrong but it seems to me that the weakness lies in having only two studs per main bearing, the load on the block from those studs could to be spread to more studs drilled and tapped into the machined part of main bearing support webs.

Of course it would be better to have a conventional type single main bearing support plate or a complete new girdle but something like that above may be sufficient. I'm not planning on doing it, interesting though.

Nice topic .. What is the status on this project .
I think someone should write a simple how to guide including all the necessary parts to complete same....ie. VG33 bore to VG37.

If you need that kind of write up, don't even try it.

Hey guys,

Read through this topic, was there an outcome with the engine? Did it get put back together for another Dyno pull using the 3.8L block? If so how did it go, is it still running?
Looking at boring a vg33 block just wanted to know what would be the max I could go. Want to run high boost with supporting mods, setting car up for sports compact Drag racing along with the occasional street use.
Any info would be appreciated.
Cheers Peoples, great site! :-D

The topic is still controversial. It was said it could be bored out to a 3.8 liter but then cracked OVER 700whp. I have not seen this engine though and neither has anyone else. RAracing1 in Puerto Rico says that you cannot bore out a VG33E more than making it a 3.4 liter due to the crank webbing on the bottom side of the block getting too thin and cracking. This is supposedly where it cracked on Zfast's block.

Again supposedly, the crank webbing on the bottom side of the VG30E and VG33E blocks is actually thinner than the later VG30DE blocks. This MAY be why you see VG30DE's in the 1000+ hp range all the time but you never see VG30E or VG33E engines in that range. Or maybe it is just because people want better flowing heads.

Basically, nobody knows for sure until you get out there and do it.

Has accepted this as truth. :-(

The twin GT35R's will get slapped on a VG34 once work slows down for me and I have time to build the engine.

[quote]ZFast88Z wrote: well since its no longer a above top secret build, lets see the "3.8"l block

No Worries guys thanks heaps for the replies, really appreciate the info.
Do you know if RARacing1's Z31 is bored out to a 3.4? Or Is that impressive power figure carried out on a 3.3.
What about yours Satan, have you started with a 3L or a 3.3L?
Sorry for all the questions guys, no one down here in Australia really touches these engines as you know the RB30 takes preference.

[quote]Chrisw_2003 wrote: [quote=ZFast88Z]I was going to ask the same thing

Rafy (RARacing1) made 737whp on a dynojet using the 3.3 liter block. Dyno jets are known to read high though, so more likely around 650whp on other dyno's.

I made just over or right at 600whp on the VG30E with 22lbs of boost. Was going to run 30psi that same day, but the VG30/33E engines have crap ass oil pumps and I a spun a rod bearing that day. SO…

I am building both a VG34E and then a VG30E as a back up.

[quote]SATAN wrote: 737whp on the stock VG33 crank?