Thread: Tuning with CIS
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Old 08-21-2011, 12:59 AM
400Eric 400Eric is offline
Knappy Drag Racer
 
Join Date: Jun 2008
Posts: 1,725
Quote:
Originally Posted by 400Eric View Post
I have no doubt that this mod works when the engine is operating at elevated temperatures, I saw it first hand with Benzer3. That's why I'm leaving the resistor hooked up so that I'll see the benefit in daily driving.

I do however need to come up with a way of advancing the timing when the engine is at around 80C. Anybody have any ideas? The one that I have come up with is to move the vacuum line the feeds the vacuum signal to the EZL to a different source, one that still maintains a little vacuum even when under WOT conditions. We used to call such a vacuum source a ported vacuum source vs. a manifold vacuum source. (But I may have that backwards though.) This would fool the EZL into thinking that the engine is under a semi part throttle condition and thus is in need of more ignition lead. Obviously, I would need to proceed with this plan slowly, gingerly, and carefully and it would have to be just a little vacuum being supplied, not a lot cause we are only after a little more ignition advance, not a lot. I'll test and monitor the different vacuum ports on the engine with my vacuum gauge under varying conditions to see which port will serve this goal best. I'm thinking the one that sucks the fuel vapors out of the charcoal canister may be a front runner for this job.

Anybody have any thoughts on any of this? There's a mid-90s Nissan Maxima that runs consistent 15.9s (my 15.9s are NOT consistent) at the track that I want to be able to spank!
Regards, Eric
Dave, you never weighed in on the above post.
Also, the difference in the amount of power robbed by automatics vs. the amount of power robbed by manuals is greater than you think. It's a known fact that some automatics rob as much as 45 horsepower! The power loss range for automatics is 18-22% while the power loss range for manuals is 15-18%. I think our 722.3 autos are at least in the 20% range. Did you know these old dinosaur 722.3s have over a thousand moving parts? Supposedly the 5 spd auto that replaced it has only about half that many moving parts. These old trannys aren't the lightest things around either. Lots of reciprocating weight!

Ed, thanks for the informative post. As I understand it, another mark against the inertia type dynos is that turbo cars don't really build full boost on them because they don't fully properly load the engine like it is loaded in the real world. Do you agree with that?

Jay, you said your chassis dyno is a Bosch dyno. Is that an eddy current load type dyno or inertia type dyno?
Regards, Eric
__________________
89 300E "Benzer1" 15.924 Uncorrected
93 400E "Benzer3" 14.200 U.C.
95 E420 "Benzer4"
92 300E "Benzer5" 16.299 U.C. Future turbo CNG
87 300D "Benzer7"
87 300D "Benzer8"
87 300D "Benzer9"
87 300D/70 AMC Javelin "Sidewinder-Benzer"
87 300TD "Benzer11"
06 E320 CDI "Benzer12"
05 E320 CDI "Benzer12A"
71 AMC Javelin AMX 401 "Sidewinder"
74 AMC Hornet 401 "C.K.10" 13.63 U.C.
74 Bricklin SV1 "Presto" AMC 360 pwrd.

Last edited by 400Eric; 08-21-2011 at 04:34 AM.
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