Help me tune my 2.2 race motor
#1
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I got a 1971 race car two weeks ago and trying to solve some poor running issues, when I'm driving the car all seems normal till I reach 2800 rpm, it starts missing and running really rough till about 3500 then it runs good with couple of misses at 5500 rpm. The problem is worst if I floor the car real quick and its less pronounced if I go gradual on the gas pedal. From the build sheet of the car here's what I know about the motor:
2.2L
pistons 85mm 10.5/1 compression
crank 66mm stoke
heads 38 intakes and 36 exhaust
valves 46 mm intake and 40mm exhaust
cams: 284 degrees intake and 270 exhaust
46 PMO carburetor
46/38 cis manifolds
46/38 venturis, 150m, 180 a/c, f16
took the car to the dyno, the car requires 100 octane but wasn't available so did some runs on 93, (I know, wont do that again) it is running very lean from 2800 to 3500 (this is when its running really rough) then it starts pulling nice but lean as well. Did some searching and I'm thinking maybe I need bigger main jets? or is it just tuning what I have? will race fuel solve the lean problem? here's the dyno runs:
2.2L
pistons 85mm 10.5/1 compression
crank 66mm stoke
heads 38 intakes and 36 exhaust
valves 46 mm intake and 40mm exhaust
cams: 284 degrees intake and 270 exhaust
46 PMO carburetor
46/38 cis manifolds
46/38 venturis, 150m, 180 a/c, f16
took the car to the dyno, the car requires 100 octane but wasn't available so did some runs on 93, (I know, wont do that again) it is running very lean from 2800 to 3500 (this is when its running really rough) then it starts pulling nice but lean as well. Did some searching and I'm thinking maybe I need bigger main jets? or is it just tuning what I have? will race fuel solve the lean problem? here's the dyno runs:
#2
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It really has 46s? I think maybe on one of the 2.4 or 2.5s with RSR cams we tried that back in the Fred Flintstone days, but I can't recall.
Suggest you work with an expert to get things dialed in..................
Suggest you work with an expert to get things dialed in..................
#3
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#4
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Bassam,
You need some serious revisions to the "package" and I have a lot more questions about your engine.
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
Call me as this one is FAR too complex for e-mails or Forums.
You need some serious revisions to the "package" and I have a lot more questions about your engine.
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
Call me as this one is FAR too complex for e-mails or Forums.
#5
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http://forums.pelicanparts.com/porsc...ace-motor.html
this is the cam I have:
#6
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