AirSpeed VW Community Forums

Technical => Engine Tech Forum => Topic started by: Stevie on December 07, 2011, 09:03:31 PM

Title: Motor build, what parts?
Post by: Stevie on December 07, 2011, 09:03:31 PM

Planning to build a 1915cc motor this winter,
Wanting a somewhat budget motor
What are some things I should spend more money on.
Some suggestions on what cam and other parts I should use.

What I am starting with is a OEM mag Case.
 have original dual port heads
Set of dual kadrons unsure of what jets to use

Thanks steve

Title: Re: Motor build, what parts?
Post by: GMB on January 12, 2012, 02:16:51 PM

For a nice reliable torquey street engine I would go with an FK-41 with 1.25:1 rockers, single HD valve springs, heavy pulley.

Stock wieght flywheel
Stock valve heads
Stock pushrods
Stock crank
Stock rods
Balance rotating assembly (crank, flywheel, rods, pistons, pulley)

Jetting on kads I'd start with 135-140 mains 55-60 idles

You will have to drill the throttle plates to make the plates sit down far enough to not engage the progression cirquit at idle.

This 1914 is the smallest engine I build these days! Works great on a 34 pict with stock rockers.

Gary.

Title: Re: Motor build, what parts?
Post by: Darren on January 12, 2012, 04:19:48 PM

If your gonna keep the heads close to stock configuration I would choose the Engle 110 cam, any more cam than that you really need bigger heads to make it work correctly.

With the Kadrons a simple mod for use with a Vacume advance 034 Dizzy gets my vote!

Gary for what it's worth the fk41 is a good cam but it really needs 1.4 Rockers ( as it's designed for )  it MUSTd also have Dual springs to keep up with the fast ramps on that cam.....
I just took apart a top end from an FK41 motor that had single springs on it and had to repair burred up keeper grooves ( signs of valve float .....) and it didn't have many miles on it.

Cheers

Title: Re: Motor build, what parts?
Post by: GMB on January 25, 2012, 01:48:47 PM

Do you think it's possible the engine has been over revved?

Title: Re: Motor build, what parts?
Post by: Darren on January 27, 2012, 04:20:39 PM

Over rev could be the case but with a light single spring on a FK series cam anything over 4500 RPM would be over revving in my opinion.

Title: Re: Motor build, what parts?
Post by: GMB on January 30, 2012, 09:27:23 AM

I agree with that RPM limit specially with the 1.4s.

I never use the 1.4s though I will only use this cam with the 1.1s or the street style 1.25s. I think with less lift the single are enough specially if kept under 5000 RPM.

You know me big torque monters is what I'm after. lots of torque right from 1000 RPM, long term reliability, with minimal service.

Title: Re: Motor build, what parts?
Post by: Bruce on January 30, 2012, 11:28:44 PM

But if you're not going over 5k rpm, why not just use a stock cam and 1.25 rockers?  That'll rev the same.

If you were skereed of double springs, just get some well used doubles.  They will be quite a bit softer than new ones.  On my current engine I put well used doubles on it from the start.  I'm up over 70k miles on my FK-44.  My intent was to do the initial break-in with these softer used springs, then upgrade to new ones.  But I never got around to doing the swap.