Anyone got any tips on what clutching to run on 200ft. dirt drags?
I'm running a 400 Scrambler
020. overbore
raceported and portangle changed
head milled 030.
39mm flatslide carb
HPD race pipe
42 tooth rear sprocket
Running on 110 octane fuel

Would appreciate any help.

 

Do you have any clutching at all or just stock?

 

Most guy's running a race mod are using HPD blue or violet primary,s-55 weights,HPD violet secondary set in the 2/2 position,44/36 helix.Hope this helps.Later.

 

Who did the race port job? there is a huge difference between different people that port. If they didnt know the proper exhaust and transfer duration, it wont make as much power, and the clutching wont work as well. Also, did you have any reason for going to a 42 tooth rear sprocket? You shouldnt do that unless your running a big tall tire like 27''. When you add alot more power, you should gear it up instead of down. You will actually lose acceleration going to such a large rear sprocket. You decrease the load on the engine, when you should be loading it more. Start with the specs CED recommended. If you dont have a tach you must have one or tuning is useless. Also go to a 14-34 gear and tune from there. You also will have an easier time keeping the front wheels down with a taller gear.Bubba

 

I'm running HPD aggressive clutch kit #CK4RM8, also a set of V-Force2 Reeds
I'll have to check just which parts this kit has.

Mill Creek Tool did my ports,took HPD jug and mapped it, then added a little more angle to the transfers
I tried a 13-30 combo on sprockets and couldn't get off the line' I'll try the14-34 to see: also thought about running a jackshaft instead of tranny.

Even with the gearing I'm running I'm still building power over 200ft mark

Thanks Guys I'll take all the help I can get

 

A wider angle (more angle) on the transfers means a broader powerband and less top end power. To gain top end power you start flattening the roof of the transfers. Hope they didnt change much, as they could have hurt the top end power output. I would really like to know which primary spring that kit has. I've always built my own and never bought a kit, so I just dont know what it comes with. I suspect it might have the blue with the 10-58 weights, but do some checking. That would explain why you cant get off the line with a taller gear. If you have that setup, the first thing I would do is to put the stock weights back in it (s-55). For racing, you definitely need the violet primary. You could shave .2 off the time from the blue. And as CED told you, make sure you are in the 2-2 setting on the rear. Keep in mind their kits are designed with alot of driveability in mind. You can still ride with the violet primary. Mike at HPD likes the violet and 10-56 weights for drag racing. I have run that setup for quite a long time. I am now running the EPI maroon with the 10-58 weights. It engages at 4800 RPMs and turns 7800RPMs on top.Although faster in the drags I think, I won't be able to dune ride it. With the HPD pipe, dont go over 7500 on top to keep in good power.Bubba