IDA main jets

[speed7]

Hey ,

would like to have your experience on the IDA jettings in my car.
It's a 2185cc , CB wedgeported heads with 44x37.5 , 10.5 CR and 55cc chambers.
IDA 48s with 42mm venturis.
Actual jetting :  F7 with 160 mains.
Should I go larger , smaller or keep my hand off ?

Thanks for sharing your experience .
Marc

[WPS]

Hi Marc,

Go 180main and 200air

Try that then maybe 185main

Oh and hold on tight!!

All the best...might see you at Bitburg?

Ian

[leec]

I run 40 mm chokes, 170 main, 200 air, 60 idle. That's what's in mine. 2276, FK87, wedgeports 10.3:1 cr

Lee

[neil68]

When I ran a similar combo, 10.7:1 CR, 044's with 44 x 37.5, 42 mm vents, I found it was useful to swap out the F7's and install F2's with 180 main and 210 air with 60 idle.  This was the result of several chassis dynojet tests and 1/4-mile racing.

[benlawrence]

Hey ,

would like to have your experience on the IDA jettings in my car.
It's a 2185cc , CB wedgeported heads with 44x37.5 , 10.5 CR and 55cc chambers.
IDA 48s with 42mm venturis.
Actual jetting :  F7 with 160 mains.
Should I go larger , smaller or keep my hand off ?

Thanks for sharing your experience .
Marc

I have a fairly similar setup although 82 x 94. same heads same compression, same carbs same vents.
dyno'd last year with a 160 main 200 air and it was lean, dyno'd this year with 180x200 and it was a touch on the rich side, 170-175 would be near as good as.

I don't think you need to go quite as far with the main but up one size wouldn't hurt. What cam are you running?

[speed7]

Hi Ben ,

I'm running on a FK87 cam .
Greetz

[speed7]

Hey guys ,

thanks for sharing !
I'll try and get the necessary jets and tubes so I can try it out @ the Pod at VW Action.  ...getting it ready also for DDD !

See ye
 Marc

[MC Dyno Don]

If its running good on the bottom end and not popping or sputtering, you can assume the idles are at least ok...if it lays down on the top end and you run out of power you then need to creep up on the mains. Run it through the lights then SHUT OFF and pull a plug as this is the only real way to troubleshoot. The plugs should NOT be white inside and you should also look for "spotting" as that will indicate timing or ignition problems.

[spanners]

If its running good on the bottom end and not popping or sputtering, you can assume the idles are at least ok...if it lays down on the top end and you run out of power you then need to creep up on the mains. Run it through the lights then SHUT OFF and pull a plug as this is the only real way to troubleshoot. The plugs should NOT be white inside and you should also look for "spotting" as that will indicate timing or ignition problems.

This... A plug chop is how I do it, dyno's  don't tell the full story, they are not at the point of battle with the prevailing conditions and variable barometric pressures. Always ere on the rich side and work from there, it's lean that costs power, runs the motor badly and torches heads and pistons,  what do you see all the time with winning high hp motors up the front? Black smoke on the shift point or over run, at least carb/petrol ones.