Stroker 304 Project Build

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   Hey guys,
Just got a response back from Endyn on the Swirl Port heads and the A/F ratios they saw with the 2-valve cylinder heads.  These are the guys that helped Bill Elliot's team, among others.  My questions way below in Purple and their response in Green.

Greg :)

From: Staff@theoldone.com <staff@theoldone.com>
Subject: Re: Question on Swirl-Port and A/F ratios (was : AMC Stroker 304 back from the Dyno)
To: amundaza@yahoo.com
Date: Monday, March 16, 2009, 10:29 AM
We were running BSFC's lower than .34 with race engines some 24 years ago with EGT's in the 900° range (measured .5 x pipe diameter from the port flange).
As long as you're not seeing detonation, or extreme temps on the exhaust side you can continue to run leaner and leaner. Of course, A/F ratio's will "freak out" those with conventional wisdom. As i recall the lowest A/F numbers we saw with 2-valve engines were in the 24-1 range at light throttle and light load conditions. 18-1 was common under load (with good atomization). Be aware that once you go far enough below stoic, the EGT's will begin heading downward.
You might want to include something like an MSD Knock Alert to your dyno instrumentation, so you can "see" detonation that's not audible should it occur.
Larry

----- Original Message ----- 
From: Greg Taylor 
To: staff@theoldone.com 
Sent: Monday, March 16, 2009 9:11 AM
Subject: Question on Swirl-Port and A/F ratios (was : AMC Stroker 304 back from the Dyno)

Hi guys,
I happened upon your website a while back via a Car Craft forum posting about your swirl-port heads.  We just finished dynoing my AMC V8, using AMC V8 swirl port heads, along with cylinder head grooves and custom pistons.  You can read about my dyno sessions below, as well as the engine build threads (listed way below) with pics, etc.

The reason I am emailing you is to ask you about the A/F ratios you see on your engines utilizing the Swirl Port technology.  My engine seemed to run normal EGTs, with lean A/F ratios and lower BSFC readings (0.39x for the Carter AFB running lean).  When we were tuning everything, the operators were trying to tune for richer than 14.7:1 A/F, which we could get at idle, but from 3,000 RPM on, everything would show a lean condition, but the EGTs were not abnormal ... I still need to get the AFB (baseline) EGTs for comparison to the FISH carb EGTs.

What kind of A/F ratios are you seeing with your modified swirl-port engines?  Thanks for the feedback.

Sincerely, 
Greg Taylor :) <>< 
Rochester Hills, MI
1989 Jeep Grand Wagoneer "TRMN8R2"
330-CID AMC Stroker V8