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Re: Biggest Crank in a Type4

Posted: Sat Jan 16, 2010 7:44 pm
by wrenchnride247
Let me rephrase my earlier post... 86mm is the biggest you can go SAFELY and RELIABLY :lol: (knew about the 90mm, but didn't think the OP wanted to go extreme $$$)

Re: Biggest Crank in a Type4

Posted: Sun Jan 17, 2010 12:07 am
by Type 4 Unleashed
wrenchnride247 wrote:Let me rephrase my earlier post... 86mm is the biggest you can go SAFELY and RELIABLY :lol: (knew about the 90mm, but didn't think the OP wanted to go extreme $$$)
Actually, one of the customers EMW had made the 90mm cranks for had previously had EMW make him a 88mm crank that he had ran for about 2 years before having them make him the 90mm one. And from that 88mm crank he was able to determine that he could run a 90mm crank.

And he's been running the 90mm crank going on 2 years.

And anyways sooner or later parts break, that's what happens when you double & triple the hp on these motors.

Re: Biggest Crank in a Type4

Posted: Sun Jan 17, 2010 1:48 am
by Wally
Question is also: will you make more hp with the 90mm crank then with a 86mm or a 82mm...?

Re: Biggest Crank in a Type4

Posted: Sun Jan 17, 2010 8:02 am
by Type 4 Unleashed
Wally wrote:Question is also: will you make more hp with the 90mm crank then with a 86mm or a 82mm...?

Then how about we continue the question, will you make more HP with a Pauter 96mm crank than you would with a 86, 88 or 90mm crank ?

I will seeif I can get the answer too: Was it worth it going from the 88 to the 90mm crank ?

Re: Biggest Crank in a Type4

Posted: Sun Jan 17, 2010 8:54 am
by Wally
Yeah, when do the diminishing returns go backwards?

Would be a much deeper discussion on flow inside the case and through the heads.
I guess if your heads would flow enough and then some, the extra displacement could surely help boost torque across the range.

Re: Biggest Crank in a Type4

Posted: Sun Jan 17, 2010 9:15 am
by fusername
yeah but you would probably need god's own heads to really take advantage of the work. taht said, I would really like to see these cranks inside a case. can't have a thread like this without some engine porn.

Re: Biggest Crank in a Type4

Posted: Sun Jan 17, 2010 3:25 pm
by Type 4 Unleashed
fusername wrote:yeah but you would probably need god's own heads to really take advantage of the work. taht said, I would really like to see these cranks inside a case. can't have a thread like this without some engine porn.
Actually heads won't be too much of a problem, most people other than myself don't run a cam large enough to need anything over a stock 2.0 ltr valved head anyways... :lol: :lol: :lol:

And with a 90mm stroke & 105mm bore or larger, velocity in the ports will never be a problem, it will be volumne that will be lacking from small ports & valves. And I have the heads to just take care of that problem... :lol:

I have a set of 5.4" Rabbit jrl Carrillo rods that I will throw on my 90mm Rabbit jrl crank tomorrow and mock it up in a case. Do to the fact I am very curious as to clearance issue's. And anyways I am already thinking about having a set of Cunningham rods done in Rabbit jrl's... :lol:

Re: Biggest Crank in a Type4

Posted: Sun Jan 17, 2010 7:57 pm
by fusername
man you get to have all the fun. tommorow I am only going to chop my keepers and wash my heads a bit more. :oops:

Re: Biggest Crank in a Type4

Posted: Sun Jan 17, 2010 8:27 pm
by Type 4 Unleashed
fusername wrote:man you get to have all the fun. tommorow I am only going to chop my keepers and wash my heads a bit more. :oops:
I don't know about having all the fun, who knows what issues I will find.

And I hate chopping keepers, untill just recently, I would just go to Gene Berg's and spend the $20 something dollars and get their pre-clearance, hardened & black oxided keepers, that they don't bother to black oxide them any more... :evil: ... just to keep from having to grind keepers.

Re: Biggest Crank in a Type4

Posted: Mon Jan 18, 2010 6:50 am
by fusername
I used to have a notch in my finger nail from doing them all the time. When i'm finally done, whats so exciting about a good set of keepers? when your done, you get the excitment of taming a 90mm crank!

Re: Biggest Crank in a Type4

Posted: Mon Jan 18, 2010 4:29 pm
by Type 4 Unleashed
There was a power outage, so finished mocking this up in the dark, and was how the pics were taken.

This is going to be fun, it hits every where... :lol:... It's not really a fair mock up, the 2.0 ltr H beams compared to these carrillo rods I used for the mock up, have the clearancing where it's need and would provide far more clearance than these did.

And the cam was a bad choice for a clearance mock up, it had a fairly large B/C along with a large lobe lift of .430".
And I didn't put the drive gear on so the cam lobes were not where they were suppose to be when the rod came around.



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