Hello fellow Sixer fanatics!

I'm building a 30+ psi 225 with a compound turbo setup. Should I look into a billet crank? I know there's some in existence.. But where? Anyone know who would get rid of such an anomaly? Should I look into getting one made?

_________________
Boosted? Only slightly.

I know where a couple are, but I don't think either one is currently for sale.

_________________
Official Cookie and Mater Tormentor.

I know a Slant racer that got a Crower billet one recently. They're about $4K. You have to think you'd break about 40 stock cranks to justify it though unless you just have money burning a hole in your pocket.

_________________
There's no such thing as too much cam....only not enough engine!

probably worth blowing up a couple to see how much they would handle

Okay cool all I needed to hear

_________________
Boosted? Only slightly.

You guys think a '70 forged crank would handle 35 pounds of boost?

_________________
Boosted? Only slightly.

It's not only about the crank. You need to worry about the main bearing caps, and webs. I think you will need to do some upgrading in that area.

_________________
Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

I would say it's more about RPMs than boost. I don't see why not. Keep it under 6000 and it'll live. Charlie is right that the block/main caps should be treated well.

Lou

_________________
Home of Slant6-powered fun machines since 1988

Well I was looking into the mains first which is what brought me to the crank. I asked my machinist if I should run some 4130 mains since there's only 4, and he said the 1045 would be strong enough since the crank would probably go before the mains

_________________
Boosted? Only slightly.

The only guys I have ever seen have any crank issues were grinding them down to Chevy rod journal size.

_________________
Official Cookie and Mater Tormentor.

Alright. We'll see what happens.

Main material..? 1044 isn't strong enough for 35 pounds of boost in my opinion. 4130.. 4340? Let me hear some ideas.

_________________
Boosted? Only slightly.

I have a crank that may resemble that..... As some one that has destroyed a slant in every way possible I think that the crank and mains are not to worry about.
Will

You can always do a main girdle to stiffen the block. But you aren't going to break a crank because of the main caps, you will break it because it only has 4 mains and most all other inline 6 cylinder engine blocks have 7. It just doesn't have enough journal support and a lot of journal overlap that makes the design weak. Even with a billet crank with only 4 mains, it will break before the same engine that has 7 mains. Just because its billet doesn't mean it still can't break.

_________________
There's no such thing as too much cam....only not enough engine!

That's right and I totally agree. However, since it's such a weak design, I'm trying to build it up as strong as possible to withstand a beating. I know it will still have limits, but I want to overcome as much as I can. I need to make sure the lower end of the rotating assembly will survive. I've already got 2,500 dumped into a block and parts and don't even have my mains ordered. Anyone know of someone that's built a main girdle for a slant? It can't be easy since the mains pertrude below the block's surface.

_________________
Boosted? Only slightly.

Here is Howard Davis' amazing engine main girdle. After you build that then you need to build a custom pan ....etc to go with it.

http://slantsix.org/forum/viewtopic.php ... llside+six
I am not at all sure I agree that it is a inherently weak design. Maybe in the extreme applications like you are talking about it needs some consideration. But there are a lot of people that have gone pretty fast with a plain Jane forged (or cast) crank. If it was a really weak design the cast cranks would be laying in great heaps outside of garages all over America.

Keep the RPM's reasonable and the crank should be fine.

Rick

_________________
2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6