Guest bastaad525 Posted October 23, 2002 Share Posted October 23, 2002 Okay... gonna rephrase the question a little bit. For guys running SU's, any SU's with any type of needles. When you pull your spark plugs how do they look? Be detailed. Also, what type of driving do you do most? Highway/streets/traffic What method do you use or have you had the most luck with for tuning your SU's? Quote Link to comment Share on other sites More sharing options...
DAW Posted October 24, 2002 Share Posted October 24, 2002 The most luck I've had tuning SUs is by custom altering needles by turning them with a drill press and squeezing at specific points with superfine sandpaper. Squeezing = richenning. Where this is done on the needle is determined by performance at a given rpm which corresponds to the position (ht) of the needle as measured by a standardized small straw or aluminum tube placed into the damper piston (oil caps off and oil drained). It's a little complex but really not that bad and the yield is great both in performance gain and efficiency (mpg). Read "How to Build & Power Tune SU Carburettors" by Des Hammill, it's a great little book which contains sound and simple methods to gain a lot of power and driveability from your engine. DAW Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted October 24, 2002 Share Posted October 24, 2002 When I was running Sm needles, my plugs were black, sooty black, and that is adjusted per the Z therapy video . I have switched to another set that is leaner, but I have not checked or driven the car enough for them to clean the plugs. I mainly have the car idling in the driveway since it hasn't been driveable until lately, but it has been up and down the road, and up and down the interstate. If I can't get then right within reason, they will go up for sale, and either webers or fuel injection will go in their place. Maybe I can be like Norm and run 12's with FI. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted October 24, 2002 Share Posted October 24, 2002 LJ you seem to be having bad luck with your SU's.... So your plugs didn't even have any clean 'patches' on them, just all black? Also, did you double check the float adjustments? I know the ZT video says it's all set when they ship, but I double checked mine before installing them and one of them was WAY off. I guess they get banged around during shipping or something. If I hadn't checked it that carb would have been running way rich. Anyways I guess there's some kind of special 'ritual' you're supposed to do before pulling them and checking them??? Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted October 24, 2002 Share Posted October 24, 2002 Well I went thru a set just like on the video, spent about 4 hours working on them and got everything balanced, and they worked ok. But on this engine, I could never get it to run properly, so I switched to this set that came on a 2.6 I bought, and it runs way better, but I haven't done anything with them. I am really thinking about getting a set of Z therapy bodies with the new shafts in them and then putting all my balanced up stuff on them, but I think if I was going to go thru all that I might as well fuel inject it. I also know where a set is that has to be from Z therapy, so I may go get those and try them and see what is up with that. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted October 25, 2002 Share Posted October 25, 2002 Going thru 'all that' really isn't that much work at all... I would think it wouldn't even come close to the work it would take to transfer all the EFI wiring over. I took my SU's off and nearly completely apart in about 1 1/2 hours. By apart I mean: took the domes off, removed the needle from the pistons, nozzles and fuel hoses completely off, float bowl lid off and jets removed. I'd say three hours tops to remove the carbs and swap all your stuff over to new bodies and reinstall them. I guess it's a relative thing though.. installing the EFI seems to be pretty difficult to me. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted October 26, 2002 Share Posted October 26, 2002 Anyone else? trying to get a good idea of what is 'normal' to see when looking at the spark plugs of an SU equipped car Quote Link to comment Share on other sites More sharing options...
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