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Discussion Starter · #1 ·
It is winter here now and not so much to do on the car, I had to find something to do.
I was not completely satisfied with the idle and light cruise up to 2000 rpm and wanted to get it leaner but still good throttle response, I have come up with a plan that we'll see if it works.
Carburetor a 2 year old PRO System
Service of the carburetor and change of IFR 37 to 31 and IAB 76 to 67 Original from PROSYSTEM was 37/76.
Distributor MSD HEI 8365
Made new bushing for the total advance now 10 degrees
The ignition 23 * + 10 * + 13 * VAC @ 8hgin = 36 * idle. and 33 * all in at 2500 rpm
(Previously 16 * + 18 * + 14 *, giving 30 * idle best as MSD only offers 18 degree bushing)

New hotter spark plug Autolite 3924 previously 3923

Adjusted idle screws after even temperatures of each header pipe and as evenly as possible on both AF gauges and high vacuum.
Resulting in (number of revolutions indicated in minutes) LF 1.15. LR 0.10 / RF1,45 RR 0.45:surprise:
Transfer Slot front square
Transfer Slot Rear 0.005
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Results idle 1050 rpm AF average 15 Vac 13,2hgin
In gear. 850 rpm AF 16 Vac 8hgin

Throttle response is very good!
So now only remains to see if it can be driven on the road as well as I thought, but there are two months left until that happens.

Some thoughts on the uneven adjusted idle screws!
 

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I can not add any technical information, but I'm surprised you had to change the air bleeds so much. 4 corner idle screws, maybe manifold distribution, or a result of air bleed changes? Just thinking, hope JMark will enlighten us.
 

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Discussion Starter · #3 ·
The way I think I see idle and transfers (IFR and IAB) as a small carburetor in the carburetor and to make it more responsive smaller holes do it.
In combination with the OD gearbox, it only takes a few% throttle to reach 2000rpm = 65mph. and then if I am right in my mind that the smaller hole IFR and the IAB will need a little more throttle opening and hopefully get a better (higher #) and smoother AF values. We'll see!
 

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Discussion Starter · #4 ·
A little good weather and an opportunity to drive the car and test the new settings to the carburetor.
Drives very well and AF remains stable and is responsive to engine speed and load in the lower RPM 800 - 3000 just as I wanted.:smile2:
 

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