350 HP Potential for CIS
William M. Lockwood-III
wlockwoo at zoo.uvm.edu
Tue Sep 19 09:08:06 EDT 2000
How does the MF2 injector driver work? I mean what is it and how does it
do its job? Can I turn up the fuel pressure on my MAC 11 car?
On Mon, 18 Sep 2000, Kaklikian, Gary wrote:
> As content as I am with CIS + MF2 injector driver with 2 motronic injectors
> on my car, I'd estimate I'm getting at most 280hp at 17psi boost even with a
> cam, p/p head, 944 compressor wheel & intercooler, etc. My car has the MC-2
> CIS, but I'm using the older-style internal, plunger-type fuel pressure
> regulator, which has been shimmed. I'm also using two fuel pumps - an UrQ
> and a 930 turbo.
> Even with an EFI, as Javad says, larger valves, a custom exhaust manifold,
> and an even larger turbo (K27?) are prerequisites for
> 350 hp. Maybe I could get more hp even with the CIS/MF2 by using a lower
> compression ratio and a larger turbo/more boost. But IMO it's not worth
> sacrificing mid-range torque for more top-end, particularly on a street car.
> (Another, taller gear would really be nice though)
> I wonder what the horsepower limit was on the 930 turbo with CIS. The 930
> used two fuel pumps, oversize fuel lines, and a large fuel distributor.
> Aren't we all just speculating on these horsepower figures anyway? Anyone
> put a Quattro with a modified 10vt on a 4wheel dyno, or even a 2wheel with
> the driveshaft removed? How accurately does the G-Tech measure horsepower?
> Gary Kaklikian
> 86 4ktq
> 92 S4
> -----Original Message-----
> From: JShadzi at aol.com [mailto:JShadzi at aol.com]
> Sent: Tuesday, September 12, 2000 11:38 PM
> To: wlockwoo at zoo.uvm.edu
> Cc: quattro at audifans.com
> Subject: Re: 350 HP Potential for CIS
> In a message dated 9/12/00 3:40:49 PM Pacific Daylight Time,
> wlockwoo at zoo.uvm.edu writes:
> << I have read different posts that indicate the Ned Ritchie says that CIS
> good for about 350 hp in a MAC-11 engine. What are the necessary steps to
> building one of these 350 hp engines? How did the rally cars using the
> 10v head get 400 hp? What injection did they
> use? Graydon? Scott? Igor? What do you guys know about this?
> If I left you out I didn't mean to...
> The race cars used EFI, some 2 injectors per cylinder. You will be hard
> pressed to push an I5 to 350 hp without seriously freeing up air
> as Todd mentioned earlier. I believe it would at minimum require a custom
> free flowing header to start with, as well as a larger, single pass IC.
> K would know about pushing CIS to its limits, but if I remember correctly he
> said about 260 was the limit for him (Gary?)
> If you did a serious port job on the head and manifold, went to bigger
> intake valves (I measured a TransAm head at Eurospec, it had 41mm/36mm
> valves), did a custom exh. manifold, a larger turbo such as RS2 or
> turbonetics, and went to an after market EFI system you could get rid of
> darn fuel dist all together. Plus, by removing fuel dist. it will make room
> for a bigger turbo and manifold. Lastly, a 4" exhaust thru the firewall
> the passenger seat out the side door to finish it up (that last one optional
> I am currently involved with a few projects converting to EFI,
> the way to go, that dist. is nothing but trouble! HTH,
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