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Wed Nov 21, 2012 3:37 pm

midtravelmidengine wrote: did you ever get it richened up or are you still lean with conservative timing?
I did adjust it a tad rich but the problem has been that I broke the USB to serial port adapter for the megajolt unit and I haven't been able to connect it to the computer to play with timing. I think I need to lower the timing a bit because I get some knocking at full throttle. Another issue I still have is that I think the carb is too small. Whenever I suddenly floor it I goes lean.

Wed Nov 21, 2012 3:45 pm

hi stickerdick great looking super charger .on your 34 pict carb . i used to drag race a 34 pict carb with out the ventura. i found that i ran out of fuel from useing a bigger jet because the small needle and seat could not keep up with the high fuel damand of the bigger main jet and the carb would fall on its ass lol . if you look at carbs with bigger venturas they allways use a bigger needle and seat most drag racers when running dual weber 48 idas allways use a 3.00 needle and seat .because a small needle and seat can not keep up with the fuel demand .the same can be said about the 34pict carb when you open the ventura up and install bigger main jet and when you rev your motor over 5,500 rpm and up or in your case when your useing a super charger that demads more fuel on top end i fixed this by useing a brosol needle and seat. i went with a 2.00 mm needle and seat .. EMPI sells the 2.00mm needle and seat the part number is 43-5023 for the 2.00mm . they allso sell a 1.75 needle seat part number 43-5022 i just wanted to say that a super charger likes a lot of fuel on top end i think the 2.00 mm needle and seat would help a lot . to stop your carb from leaning out .like the guys have said on this forum try a 28mm ventura i am like you i like the stock 26mm ventura for a street motor and in town driveing . but i had a 30mm ventura in my 34pict carb on my street motor and it was great for top end power and drag racing just my two cents spencerfvee got to looking in my jet box i have a 200mm needle and seat and a 1.75 needle and seat you can have them for free if that will help you out spencerfvee el Mao wrote: Stickerdick wrote: I got my SC12 in on Thursday, got the bracket from Vintage speed coming next week, got the mockup motor out and I'm trying to decide which type of trigger ignition to use, but you have inspired me, so I'm going for it, I'll post pics after I get started. Wish Me Luck.

It's been a while since I checked this thread but I like what I see. If you want some close-up pics of the bracket tabs let me know.
I highly recommend the megajolt system. It is not hard at all to install and once you have it going you can fine tune it to your needs. Plus you can later megasquirt it if you wish.

So far the hardest thing has been the Carb. I finally ended up going to a stock 34 pict 3 german carb with the venturi. That carb I initially had, without the venturi, was a pain. Now I have better throttle responce and it stays around stoich throughout the whole RPM range.

Stickerdick: I recommend that if you are doing the SC12 you go with a larger carb. What are you engine specs?

Thu Nov 22, 2012 2:02 pm

If it runs lean when you floor it in the midrange the carb or venturi is too large or the jetting is off.

T

Wed Dec 11, 2013 5:22 am