dellorto side draft tuning questions

[Mateepay]

i have a dellorto side draft that was on my sp 12a had 147k miles when i lost rear rotor compression. when i pulled my motor to replace it with a recently purchased low miles motor i noticed the rear housing exhaust port was very white and the front was black. im assuming from general knowledge that my rear housing was running leaner than the front hence the failure. i am running two different sized jets front was 220 and the rear was 230 if i remember correct.

im curious on some input i would like to keep the motor lasting as long as i can this time around. :squint:

[t_g_farrell]

Theres no reason those jets should be different. I would check the jetting
at this site and compare what you have and verify its in the ballpark for the
new motor. I'm assuming the new one is SP as well?

www.gruntled.com/Dellorto

You may also want to rebuild your Dell as it could be a block idle mixture screw
or some other passage clogged with debris. Go to this site for your rebuild needs:

www.dellorto.com

They are in england but ship fairly quickly and can help you if you have questions.

[Mateepay]

Well I rebuilt the card with a kit supplied by dellorto on my last motor it was only on for maybe 3-4k. My delema is I'm very new to carburator tuning and have had no success. I've read quite a bit on the grunted site I guess that should be my best bet on tuning? And yes it is stock port I also forgot to mention I'm running a full street port racing beat exhaust

[PercentSevenC]

Cross jetting without dual wideband/EGT sounds like a bad idea to me. I'd start by setting everything the same between the front and rear rotors.

[Mateepay]

Sweet I will give the advice a try t g farrell much appreciated : percent seven c I will order the correct jets and give that a try

Thanks again for the fast and knowledgeable responses