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PostPosted: Tue Oct 06, 2009 9:41 pm 
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can i do the offset regrind like this with a 84 stroke vw journal crank to a 86 chevy journal and still be reliable and able to rev high without worry of it breaking? by the way it is "supposed" to be one of those $800 scat crankshafts (i bought the engine already together from a guy who sold out) if that matters any :?

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Reply with quoteReport this postRe: w 125 cam with 1.25 rockers????
by rockrockets1 on Tue Oct 06, 2009 8:22 pm

Is it a counterweighted crank? if so have it turned to a off set small journal ...Around here they call it a cheater crank ...You can get almost 71 stroke ...$99 bucks for a set of CB performance Chevy rods 2 inThats as cheap as you can get HP

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Last edited by ridenrace6 on Wed Oct 07, 2009 2:14 pm, edited 5 times in total.

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PostPosted: Tue Oct 06, 2009 9:45 pm 
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Yep


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PostPosted: Wed Oct 07, 2009 2:16 pm 
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what would be the best length rod for this setup?

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PostPosted: Wed Oct 07, 2009 3:05 pm 
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you want to spin it up, or try to get grunt? 5.7s for grunt, 5.5's or so for top end.
I like the 5.7's personally. Mine n kokos run them. Got 5.5s in wifes 2276, it feels like it makes its most power higher in rpm than both of ours, and its only got 041s on it. But nowhere near the low n mid pull.


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PostPosted: Wed Oct 07, 2009 4:24 pm 
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kybuggy1 wrote:
you want to spin it up, or try to get grunt? 5.7s for grunt, 5.5's or so for top end.
I like the 5.7's personally. Mine n kokos run them. Got 5.5s in wifes 2276, it feels like it makes its most power higher in rpm than both of ours, and its only got 041s on it. But nowhere near the low n mid pull.


i really want both top and bottom but i know you cant have your cake and eat it too, so would 5.6 be a good compromise?

ive got cb 044 heads on it not sure of valve size or port work and am gonna run a 110 cam with 1.25 rockers.

also should i go with a heavy (stock) flywheel or lightened as i have both already?

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PostPosted: Wed Oct 07, 2009 8:53 pm 
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5.6 well be good . offset grind crank about $125 to ? call 812 432 9100


Last edited by hyde on Wed Oct 07, 2009 9:16 pm, edited 1 time in total.

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PostPosted: Wed Oct 07, 2009 9:09 pm 
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With an 86 crank you wont miss the rotating mass (felt as torque) of the heavy flywheel, I'd run the lightened one.

Well, it aint like the 5.7s will just kill your top end , just like the shorter ones dont mean you will have no torque at all.

If your gonna race it or something, I'd go with the shorter ones. But for the woods, I'll think you will be happiest with 5.7s. If you already got something else, go with it though. Ought to be a great woods combo you got there with a set of 40's on top of it all, as long as nobody has hogged out the 044's real bad. Just be sure to use ARP rod bolts.

The offset crank grinding is fine, I guess. Koko's 2387 is goin on 6 yrs or so with one in it, no problems yet. It cost $75 when I had it done.


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PostPosted: Wed Oct 07, 2009 9:11 pm 
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a heavy flywheel is better in a grunt motor,when u go up a hill a lightweight flywheel will blow the tires off and a heavy flywheel will kinda start off slower


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PostPosted: Wed Oct 07, 2009 10:34 pm 
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kybuggy1 wrote:
. Ought to be a great woods combo you got there with a set of 40's on top of it all, as long as nobody has hogged out the 044's real bad.


ive got 44's sittin on top right now. and i think the 044's are straight out of the box just not sure of the valve size.

any idea without mocking it up of what size barrle shims ill need so that i can order them while the crank is in the shop

ill also have to order the rods as mine are vw journal and no idea what length they are but it has 2 maybe .060" barrle shims under the jugs now? that is why i was wandering about the 5.6" rods as being a "compromise" between rpm and grunt?

i like racing but i guess ill probably go with the 5.7's

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PostPosted: Wed Oct 07, 2009 11:14 pm 
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No way that I know of to guesstimate on the barrell shims without stickin it together. Depends on what compression you are gonna shoot for too.

44's will be fine. Maybe a hair shy of the 40's in response, but you'll benefit from the 44s at WOT. Depending on type of riding you'll do mostly (I see alot of different stuff called "Woods" riding), might want to get the smallest venturiis you can get for the 44's ( I think its 32mm) to get the best throttle response. So many variables involved, just depends on how YOU like it and what works on YOUR buggy. No dead set best formula to go by for everywhere and everyone.


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PostPosted: Thu Oct 08, 2009 2:19 am 
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kybuggy1 wrote:
Depends on what compression you are gonna shoot for too.


i guess more is better but i want to be able to run on 93 octane just in case im out of the "good" stuff and cant get any in a hurry for a "out of the load up and go" unexpected ride......or maybe lower is better any suggestions?

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PostPosted: Thu Oct 08, 2009 7:13 am 
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to run 93 octane u will have to have .060 thous. deck height,so u might have to have a .090 shim under the cylinder maybe bigger,,,i got a .090 with about .050 deck height and i have to mix my fuel,somewhere around 100 octane


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PostPosted: Thu Oct 08, 2009 8:54 am 
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How can you know what deck heigth is needed without knowing the cc's of his heads? I know he said they was "stock", but they still need to be cc'ed. There are several configurations of "044's" right off the shelf with anywhere from 50 - 70cc's.
ridenrace6 wrote:
i guess more is better but i want to be able to run on 93 octane just in case im out of the "good" stuff and cant get any in a hurry for a "out of the load up and go" unexpected ride......or maybe lower is better any suggestions?

93 is fine up to 10:1, 10.5 :1 if its not tuned too lean or too much spark advance, and you dont try to smoke it in hot weather. There is NO benenfit to running higher octane fuel just sometimes. Its either set up for it , or its not. Yoo may see a slight benefit from running race gas if you bump your timing up a little. But with a 10:1 motor, pouring some 110 in it and making no other changes aint gonna do nothing . The slower flame front might even hurt performance.


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PostPosted: Thu Oct 08, 2009 5:20 pm 
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Kybuggy is right. You want the fuel to basically "explode" in your cylinder. The lower octane your are capable of running the better. Dont waste your money on race fuel if you dont have to. Basically all the octane does is slow the "flame front" or propogation properties of the fuel to eliminate pre-ignition or "spark knock/pinging". Low octane fuel in a "high" compression ratio engine has a tendency to "light up" before the plug fires at times. Similar to running your engine very lean.














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PostPosted: Thu Oct 08, 2009 6:50 pm 
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kybuggy, you are wrong but also right on your rod stroke length. the 5.7 rods in the 2387 has a rod stroke ratio of 1.68. The rod stroke ratio in the 2276 with the 5.5 rods is 1.70. The higher the rod stroke ratio, the higher the RPM the horsepower and torque will happen. SO 86 by 25.4 is 3.385 5.7 by 3.385 is 1.68 rod stroke 5.6 rod is 1.65 & 5.5 is 1.62. The bigger number= higher RPM. Smaller number= lower RPM.


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PostPosted: Thu Oct 08, 2009 9:18 pm 
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Don't know about up there but down here compression is HP :wink: it's also heat..... But it's HP..... :) cheap HP


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PostPosted: Thu Oct 08, 2009 9:44 pm 
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kybuggy1 wrote:
With an 86 crank you wont miss the rotating mass (felt as torque) of the heavy flywheel, I'd run the lightened one.

Well, it aint like the 5.7s will just kill your top end , just like the shorter ones dont mean you will have no torque at all.

If your gonna race it or something, I'd go with the shorter ones. But for the woods, I'll think you will be happiest with 5.7s. If you already got something else, go with it though. Ought to be a great woods combo you got there with a set of 40's on top of it all, as long as nobody has hogged out the 044's real bad. Just be sure to use ARP rod bolts.

The offset crank grinding is fine, I guess. Koko's 2387 is goin on 6 yrs or so with one in it, no problems yet. It cost $75 when I had it done.

hyde wrote:
kybuggy, you are wrong but also right on your rod stroke length. the 5.7 rods in the 2387 has a rod stroke ratio of 1.68. The rod stroke ratio in the 2276 with the 5.5 rods is 1.70. The higher the rod stroke ratio, the higher the RPM the horsepower and torque will happen. SO 86 by 25.4 is 3.385 5.7 by 3.385 is 1.68 rod stroke 5.6 rod is 1.65 & 5.5 is 1.62. The bigger number= higher RPM. Smaller number= lower RPM.


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PostPosted: Thu Oct 08, 2009 9:48 pm 
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rockrockets1 wrote:
Don't know about up there but down here compression is HP :wink: it's also heat..... But it's HP..... :) cheap HP

Yep up here to .


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PostPosted: Thu Oct 08, 2009 9:50 pm 
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Hyde met a guy down here that spoke very well of you


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PostPosted: Thu Oct 08, 2009 9:54 pm 
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O SHIT :mrgreen:


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PostPosted: Thu Oct 08, 2009 9:56 pm 
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He said up north you were called GOOD GUY KEVIN HYDE


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PostPosted: Thu Oct 08, 2009 9:58 pm 
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It was Wyoming 1 ...He came down and got a trany from me


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PostPosted: Thu Oct 08, 2009 10:00 pm 
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Sometimes how said that j-ckass


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PostPosted: Thu Oct 08, 2009 10:02 pm 
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WELL see Matt sat. at the race at Cacey


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PostPosted: Thu Oct 08, 2009 10:37 pm 
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so what is this?

hyde wrote:
SO 86 by 25.4 is 3.385




lets make sure i got this right......longer rod = less top end rpm but more bottom end torque and shorter rod = more top end rpm but with less bottom end torque

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