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 on: Today at 08:11:36 PM 
Started by crazycraftsman - Last post by Rocket Ron
cSorry for the confusion on the matter the only eng. I 've ever built with gov. in it went back on a grass cutter  . and the cast pistons in them held up very well at 3600 rpm . wish you luck at 5 grand plus at5 grand plus.

 on: Today at 07:13:13 PM 
Started by crazycraftsman - Last post by chavez
Maybe my mis-understanding,  but doesn't target rpm play into the equation?  I understand using the longer rod to slow piston acceleration and increasing dwell time at tdc/bdc. Given intake port velocity as force for cylinder filling, the longer dwell time makes sense.  But, what's ideal for a 7000 rpm engine isn't the same as 5000.  I'm trying to take the fact the stock parts are designed for 36-3700 rpm and optimize for use at 5000.  As Ron stated, maybe I am in over my head, but that's why I'm trying to ask questions in order to better understand.  Yes a different camshaft would be the first place to start, but our rules won't allow it.

 on: Today at 07:02:18 PM 
Started by biker - Last post by BIG AL 202

 on: Today at 05:36:18 PM 
Started by Big Mike - Last post by Big Mike
25 command vtwin what are oil pan & cyl head torque specs

 on: Today at 05:27:28 PM 
Started by biker - Last post by biker
Wow 2 more great replies. Now decisions to make. By the way, where do you get the 1 1/4 stock?? confused 
Wow 2 more great replies. Now I have decisions to make. That kit looks really good, where do you find that 1 1/4 stock? confused 

 on: Today at 05:05:48 PM 
Started by crazycraftsman - Last post by Rocket Ron
Thank's Jeff but I sure that one would have been way over thair head's. So I did'nt even try to explain. Ron.

 on: Today at 10:10:59 AM 
Started by biker - Last post by Huffy044
I used 1 1/4" hexagon stock, then used 5/8" heim joints tightened up to the stock for bearings, the hex gives a nice place to weld the bolt to. By the way, I have the spindle jig and axle jig that I may no longer use if anyone is intrested in it? great scrub angle, works with 8" wide front rims, the Zero Tolerance used them for many wins?

 on: Today at 09:49:51 AM 
Started by biker - Last post by mark @ EC
731 spindle bearing housing they require 730 bearings


You can find more parts for front axles here

If you need a front axle component kit we have a black friday deal for one

 on: Today at 09:44:59 AM 
Started by George Herrin - Last post by mark @ EC
BLACK FRIDAY DEALS are UP! Over 50 items are discounted including 420cc clones for $300, 4-Disc Clutch for $350 with 13 tooth #40 Driver. And much more. All order must be made online before Tuesday Dec 1st at 8am CST to receive discounts.


 on: Today at 09:11:48 AM 
Started by crazycraftsman - Last post by Jeff McKelroy #55A
What Ron is trying to explain is that basically connecting rod length plays a role in how the engine will behave. Let's look at the model 21 engine. Ever noticed why the intake is short with a larger i.d. than the 31/33? And why the combustion chamber so shrouded? Then answer is a shorter rod. A short rod will pull massive amounts of air into the engine, but not expel it very easily. Hence a larger induction system to lower port velocity. The combustion chamber is heavily shrouded for the same reason. Though valve curtain area is poor, you will still have moderately good swirl, and all the gases are 'funneled' to the exhaust valve. But this can be fixed. Enter rod ratio. By lengthening the connecting rod, you can find the desired balance between intake and exhaust events, i.e., appropriate flow through the cylinder head, not just one side of the head. Design engineers like to say a rod ratio anywhere from 1.2-1.8:1 is best. And here's where it will get costly, if you do not use the currently available off-the-shelf parts. Changing rod length means changing piston compression height. There IS a limit. Piston speed and the angles between crankshaft to connecting rod, and connecting rod to piston are all factors that must be considered. And bigger is not always better, as you will find with broken skirts and crankpins.

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