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 4150 runs rich at light cruise 
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Joined: Fri May 20, 2016 5:18 am
Posts: 105
Quote:
LSAB are 84 sec and 90 primary .

Think your LSAB are to large and possible tailoring of the transition circuit a little to son before main starts up
and 2,1/2 turns on idle screws is confirming that


Thu Apr 20, 2017 9:21 am
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Joined: Tue Aug 19, 2014 3:11 pm
Posts: 33
Tobbemek , interesting . Lots of opinions on where the mixture screws should be and what that tells you . I remember a conversation with Patrick at Pro Systems where he wanted the screws on his carbs at 2 turns out +/- . He said that atomized the fuel better. I don`t really know if that`s true or not .... that`s what he said .
That said , on this carb , everytime I went larger on the LSAB`s , the low end got better . Again , that said , I haven`t dropped the LSAB sizes since going to the larger TSR `s .... which I hope to play with tomorrow .


Thu Apr 20, 2017 11:12 am
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Joined: Fri May 20, 2016 5:18 am
Posts: 105
Didn't mean to lecture you whats right ore wrong, just think it simplify the calibration if one stay in between the ranges that most carbs work ok
and "old Holley style" carbs was intended to function properly. And like Tuner tells us not to engine alike".
Right now i am working on sort out a 70 GTX 440 Hp std long block with Eddy performer intake, headers and Holley 9379 750 cfm annular competition
and like Holley say on there H-page " racing fuel curve " runs stupid rich of cause and with "no converter" and 3,23 something gears would bee
more apropriet with a 3310 VS type anyway the jetting in the 9379 is
PMJ 68 SMJ 81
PV 6,5 plugg
PVCR dont have the nots in front of me but .050-.065 range
IFR.034 IFR .034
IAB.064 IAB .064
MAB.028 MAB .028
Front plates drilled .084
Trsl restr none


Sat Apr 22, 2017 4:32 am
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Joined: Fri May 20, 2016 5:18 am
Posts: 105
Quote:
Didn't mean to lecture you whats right ore wrong, just think it simplify the calibration if one stay in between the ranges that most carbs work ok
and "old Holley style" carbs was intended to function properly. And like Tuner tells us not to engine alike".
Right now i am working on sort out a 70 GTX 440 Hp std long block with Eddy performer intake, headers and Holley 9379 750 cfm annular competition
and like Holley say on there H-page " racing fuel curve " runs stupid rich of cause and with "no converter" and 3,23 something gears would bee
more apropriet with a 3310 VS type anyway the jetting in the 9379 is
PMJ 68 SMJ 81
PV 6,5 plugg
PVCR dont have the nots in front of me but .050-.065 range
IFR.034 IFR .034
IAB.064 IAB .064
MAB.028 MAB .028
Front plates drilled .084
Trsl restr none


Sorry forgot to say the 440 has a compcam hyd XE 284 240-246 -050 500" lift
and idle scr very sensitive .6-.7 tutrns out on idle


Sat Apr 22, 2017 6:18 am
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Joined: Tue Aug 19, 2014 3:11 pm
Posts: 33
No problem and I didn`t take it as that . I was just remarking that I hear everything from 1 1/4 turns out to what Patrick said at 2 to 2 1/4 turns . As you said ( and others ) , give the engine what it wants , and for some reason , mine appears to be the happiest at 2 to 2 1/4 turns out . On the dyno , the lambda ratios ranged from low 13`s to mid 13`s at WOT with the current setup . Once I replace the throttle blades with the holes on the primary and locked the distributor at 35 degrees , I was able to tune the TSR and IFR`s better.

What was a big help was what someone here told me . A real long cam with lots of overlap has a relatively small sweet spot on carb tuning . I was making big changes to see what happened and was going too far . When I started making much smaller changes , good things started happening .


Sat Apr 22, 2017 9:57 am
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