<VV> 140 performance upgrades

[kevin nash]

> Message: 6
> Date: Sun, 6 Jun 2010 16:55:50 -0400
> From: "Ray R. \(aka Grymm\)" <vairguy at echoes.net>
> Subject: <VV> 140 performance upgrades?
> To: <virtualvairs at corvair.org>
> Message-ID: <1C7ABC5B699C431B85F297B2E07DBCA3 at PWNT>
> Content-Type: text/plain; charset="iso-8859-1"
> 
> This post was inspired by my recent post that included the results of my 280 cam 140 build.
> 
> I was wondering what advice you guys might have to offer on 140 performance builds based on experience. I do have the book "How to Hotrod Corvair engines" and have read it cover to cover.
> 
> One of my 140's is bored to the max (on stock cylinders), has the 280 Isky cam with correct valve springs etc., forged pistons, the step was mostly machined out of the heads by the previous owner and the ports were cleaned up as best as could be by a pro without cutting the heads open. I have a pertronix II ignition with the flamethrower coil. I also have 2.5 inch performance mufflers which I'm sure (through lack of back pressure) move the torque curve even higher.
> 
> The problem is that the engine doesn't really make power (no surprise due to cam) till near 3500RPM and is still pulling hard by the time I'm not willing to rev it any further. Now I really wanted a "lopey" sounding idle and bragging rights more than the ability to outrun anyone (I don't really drive that hard.. just wanted an engine to match the aggressive looks) so it's not a big deal.
> 
> As a result (and maybe I did do something wrong, advice welcome!) I don't seem to get 1/4 mile times (by rough measurement) noticeably faster than what I read a new stock 140 did... possibly because I won't wind it out that far. I "raced" my brothers stock toyota Prius 5 speed 1/4 mile on the highway while it was deserted late at night... the cars were so close that out of 2 tests I won once by a few feet, and he won once by a few feet. 
> 
> So, for future builds what is the best combination to hotrod a 140 for performance on a tight budget.. probably no room for VW cans or anything on my budget! Maybe a torquey rather than revvy build though I would really miss the sound of that cam!
> 
> I know this might be better posted to fastvairs, but I never felt like I belonged on that list when I joined it for a short bit... more about "racing" than my basic hotrod stuff.
> 
> 
> Ray "Grymm" Rodriguez III
> Lake Ariel, PA
> CORSA member
> 66' Corsa 140/4 coupe
> 65' Corsa 140/4 coupe (under construction and almost done!)
> 
> ------------------------------
  Ray-

With a radical cam, the compression ratio needs to be higher than 

stock, as the cam is "bleeding off" cylinder pressure at lower rpms, owing

to the later closing intake and the earlier closing exhaust. I'm guessing

that your compression ratio needs to be around 10-10.5 to 1 to work

right. Also, radical cams exaggerate flow losses in stock heads, and will

be very peaky without head work. So, consider lopping off the intake

manifold, and run a set of triple throat webers. This combination will

work perfect with that baad @ss lumpy cam!

Kevin Nash
 		 	   		  
_________________________________________________________________
Hotmail has tools for the New Busy. Search, chat and e-mail from your inbox.
http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_1