ROD RATIO ??

Bugmunn · Post by **Bugmunn** » Wed Oct 09, 2002 7:53 pm

I READ ONCE THAT A RATIO OF 2:1 WAS THE BEST TO HAVE ON WEAR FOR THE MOTOR. I WILL BE BUYING A 90 STROKE CRANK BUT SEE THAT MOST PEOPLE USE A 5.7 ROD WHICH WOULD ONLY BE A RATIO OF 1:6. BUY RUNNING SMALLER RATIOS WILL YOU BE GAINING IN POWER OR LOSING?
THANX BUGMUNN

evil_vw · Post by **evil_vw** » Wed Oct 09, 2002 7:58 pm

a 90 stroke crank? are you sure about that? what is this crank going in, your trans-Atlantic submarine??

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"OK, got the duct tape, JB weld, bailing wire, and a big hammer- everything should be fine."

Searoy · Post by **Searoy** » Wed Oct 09, 2002 8:04 pm

2:1 is probably unneccesary. 1.75 is usually just great, with 1.85: being superb. These both rev really good. For neck snapping acceleration however, you want short rods, ratios onthe order of 1.5-1.65:1.

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*** Teach a Man to Fish ***
Darth Searoy

"I tend to lean toward a tighter gap and a
looser skirt....a little slap never hurt." --
Joe Locicero a.k.a. Joe of the West

Bugmunn · Post by **Bugmunn** » Wed Oct 09, 2002 8:11 pm

I always like how some people reply when someone asks a concerning question. Anyway its not a sub its a manx which just needs a little more power since I need a new crank.

tobiism · Post by **tobiism** » Wed Oct 09, 2002 8:15 pm

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Bugmunn:
I always like how some people reply when someone asks a concerning question. Anyway its not a sub its a manx which just needs a little more power since I need a new crank. <HR></BLOCKQUOTE>

Evil_VW was replying in your best interest, just in his own special way. You are aware of what is required to run a 90mm crank, are you not? What are you running in the manx now, Type 1 or Type 4?

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"There has never been a genius without a hint of madness." -Albert Einstein

[This message has been edited by tobiism (edited 10-09-2002).]

Marty · Post by **Marty** » Wed Oct 09, 2002 8:15 pm

I would not squeeze anything larger than an 86mm crank in a stock type case (I have done bigger). If you go with an 86, go with a 5.7 rod. Also dont forget the Chevy 2" journals.

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Marty Staggs
www.staggsracing.com

evil_vw · Post by **evil_vw** » Wed Oct 09, 2002 8:25 pm

[QUOTE]Originally posted by tobiism:
<B> Evil_VW was replying in your best interest, just in his own special way. You are aware of what is required to run a 90mm crank, are you not? What are you running in the manx now, Type 1 or Type 4?

</B>
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Thats Right!!! Thats Exactly Right!!!Finally!!! someone understands me!!! HOLY CRAP!!! (can you just imagine what UMD would have said to that??)

anyway, yes- i was just "saying" that a 90 mm crank is enormous, you dont hear too many ppl using one for any practical purpose. also noticed your post history pool is a little shallow, and assumed that maybe you're fairly new to the VW circus so perhaps you meant something else. no offense intended. (this time- just stay on my good side!)

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"OK, got the duct tape, JB weld, bailing wire, and a big hammer- everything should be fine."

Bugmunn · Post by **Bugmunn** » Wed Oct 09, 2002 8:27 pm

Well I have not bought the crank as of yet.
Im mainly doing research as of this week.
I had a 84 stroke with 5.5 chev rods in it but the flywheel came loose and hurt some things. The comp is almost at 13 to 1 now.

evil_vw · Post by **evil_vw** » Wed Oct 09, 2002 8:33 pm

on a side note, short rods create exessive side-load on the piston, which will wear your cylinders, bearings and rings very quickly. 5.5 to 5.7 rod length for a stroker is in the normal arena. also remember, longer rods and a bigger stroke makes for a wider motor, if space is a concern-- in a Manx it may not be.

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"OK, got the duct tape, JB weld, bailing wire, and a big hammer- everything should be fine."

Ugly Man Dinner · Post by **Ugly Man Dinner** » Sun Oct 20, 2002 11:44 am

hm, what would i have said to that? i would have said, look, hes responding like me and people understand when he talks like that. i wonder why they dont when i do....

James2 · Post by **James2** » Sun Oct 20, 2002 11:51 am

If you building a 90mm stroke Type 1, we should be asking you questions.

BTW, 1.75 rod ratio is perfect.

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Sun Oct 20, 2002 2:07 pm

I'm with Marty....and with a 6" rod you'll have some nasty cylinder shimmage unless you have the pistons custom made, and even then it'l be wild..

Stay a little tamer, I'll take a better built smaller engine anyday over a huge animal.

Bugmunn · Post by **Bugmunn** » Sun Oct 20, 2002 3:25 pm

Thanks guys for your input. I decided to go with a 86 flanged crank with chev journals,
fk 89 cam, super flow heads,13 to 1 comp and some 48 idas I got laying around. I think this should make the old manx run good for the time being. Has anyone ever made there own folts axle setup before for use with bus box? Thanx Bugmunn!!

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Mon Oct 21, 2002 12:13 am

Someone attempting a 90mm cranked engines should not need to ask these questions...this is gonna be interesting..

I shoot for 1.75 as well, as per the "Ricardo Rule"