lawndoggie

I also run a 2 mm split... can you tell me the charateristic of running a overdrive and underdrive?
By running a 2mm split with stock gears/pulleys, I am running overdrive yea?

InitialD

Overdrive is good on small tracks when you want on power steering. Off power, it will be a little understeer. It sometimes give a nice feeling of the car's front pulling the rear in and out of the corners on throttle. With too much front overdrive, the tail end of the car looses traction and swings out a lot.

Underdrive is when the rear pushes the front. Understeer on power but off power you get a lot of steering.

Front tires 2 mm bigger than rear tires or the other way around? Bigger front tires = (front) overdrive. Bigger rear tires = underdrive (rear pushing the front). Of course, this is with stock internal pulleys.

CraigH

I looked on Serpent site but didnt see a front diff option. Can you install a front diff?

lawndoggie

ack! Front 60 and read 62, no wonder I felt it was difficult entering 90degree turns with 50% or more throttle...... will try 60/60 next time...

InitialD

Ummm, the front diff will come in a form of a ball diff which would be optional item.

InitialD

Best and safest is to stick with equal front and rear tire diameters.

utopian

I think I haven't talk with you. May be you talked with my friend who drove a NTC3 with a Rossi 3 ports Rossi and flying on the track. I did not notice anybody driving Serpent at PYC other than me. All guys say that Impulse or 705 are not suitable at small track like PYC. My secret is to place a foam or sponge inside the diaphragm to increase the rate of rebound at the rear shock when compressed. Your car will turn at every corner under your control. The large rear tire will create a rear wheel drive effect, which not only reduce drag from front wheels at straight, which also reduce the 'Push' in 4 wheel drive car.

InitialD

I think Serpent officially has this small foam inserts for the shocks already. Before this, some people were using small fuel tubing cuttings or the small foam inserts from the bumper hole cuttings to fit behind the shock rubber diaphragm.

From my understanding, push will be reduced off power but on power, the push will be there if the car is underdriven.

Wouldn't a "rear" wheel drive car be more difficult to control under throttle out of the corners? I find that the car tails a lot when you punch out of the corners when the rear tires are bigger (underdrive)...

utopian

I put the insert at the rear wheel only so the rear will quickly return to its normal position after turn. This setting has long been adopted at EP at technical track. If you put the inserts at both shock, the effect will be off set.
Off power to reduce the push will slow down you car. So, I always set up my car so that it will not 'push' on on-power corning.
If you find excessive slip at the rear while on power out of a turn, try to change to a softer spring may fix the problem. I have to make adjustment based on the actual condition of the track.

InitialD

Yes, I notice that AE carried this design onward to their NTC3.

Wouldn't using a larger rear tire than front (with stock internal pulleys) make the on power push problem worse? I think on power push would be eliminated if larger FRONT tires (or overdrive) was used instead. Just my 2 cents.

border r/c

the part nr is 802370
see the site http://shop.the-border.nl

InitialD

Don't forget the left (802371) and right (802373) diff axles too.

lawndoggie

Sure I met you man!! There was this one dude with an impulse pro, and a broken bottom rear arm! I acked you about your purple rim, you said your friend gave you those GQ tires right!??
ANd told me they sell them at ACO!
Anyway, will you be going again this coming Saturday>?
Will be nice to have another snaker around!

utopian

I remember the only stranger I taught with was the unlucky guy hit by me. He took away my rear dog bone left on the track! After hitting him, I only noticed the damaged rear arm and forgot the dog bone. The color of my present body cell for my Impulse is red at the fore and silver at rear with a yellow hood. Do call me when you see my car running on the track!
The tire with purple rim is suitable for Impact and 835 only! Not for TC.
I have not made up my mind whether I will go to PYC again on coming Saturday. In fact, I did enjoy the feeling of playing at a tight small track like PYC on last Saturday.

lawndoggie

Where do you usually go?? I think there are only 3 tracks in HK.
PYC is the smallest, Kai Tak is not that much bigger, I haven't been to ACO, I heard is huge! Though I am worried about the 1/8 hitting me.. and my car!