InitialD

Jack, thanks for the input Now we know that the Picco Centax cluthbell cannot be used on the Serpent Centax.

p/s: Oh yes, 2nd page already

toolmon

Now this is what it’s all about…racers helping racers!!!

I’ll get the Neo pinion.

I also thought about changing the internal ratio. The only thing is you need the 47T diff pulley, which I think is only available for the ball diff. I'm still using the standard gear diff. Maybe it's time to upgrade...LOL...or even better get the 705 when its released…which I know I’ll do…how about you guys?

InitialD

I don't know but the thing is my PRO is already three quarter way to becoming a 705, less the new upper deck, new chassis, new tank, stifferners, rear bearing blocks, new PHQ bearings, new lightened 2 speed gearbox and Centax II. When the upgrade kit comes out, I'll probably decide then if it's cheaper to upgrade from where my PRO kit is already at or get a 705.

I fact I think I have better parts in my PRO than what is available to the 705

As for changing the internal gearing ratio of the PRO, yes, you need a 47T diff pulley. You are correct to say that it is not available for the normal rear gear diff. You need the parts available for the Impact to be able to do the conversion on the PRO kit.

Other parts needed include the following;

9614 Aluminum brake pulley adapter
909242 22T pulley
9619 MK2 adapter

The new part which is a 17T side 2 speed shaft pulley will be available. This part will fit into the 9619 MK2 adapter.

Also, new parts will come out for the spurs of the new lightened 2 speed gearbox which would inlcude the 50T 1st gear spur needed to change to a lower internal gearing ratio. On an current 2 speed gearbox, you can cointinue to use the standard 50T 1st gear spur with the Centax.

All this will make your car have the same effect as having a 14T pinion. A little long winded solution by Serpent but I think coming out with a new 14T pinion part would be better don't you think?

Distroey

me thinks you should buy the new 705 kit and race it up against your pro to see if it is any faster =)

Jack

no problem.... but i wish the picco would fit though
cause it so nice. and it light too...

toolmon

I agree. Serpent should have just made a 14-tooth pinion instead of changing the internal ratio, so us Impulse owners would not feel left out. Maybe they have some other reason that we don’t know…oh well.

I think I’ll just get a 705 instead of upgrading my Impulse. I’ve put in quite a bit into it to make it into a PRO. If I buy the 705 kit, I’ll have one car (PRO) for parking lot racing and the 705 for bigger tracks.

InitialD

If anybody is interested, I've done some conversion job on the front mid bearing block pulleys to include the one from Impact. Notice that I had to shim the 24T pulley out by about 2 mm to get the rear 18T pulley on the 2 speed shaft (also modified to Impact style pulleys).

You can use 16T (909236) and 24T (909244) pulleys from the Vector but you need to use the 909250 alumimum pulley adapter meant for the Vector. They come in a pair.

InitialD

I have also done some modifications to include the Impact GTP body mount on the Impulse.

Serpent says this cannot be done with the 7 mm spacer on the top of the rear hub as this gets in the way. I have used a cable tie to attach the body mount support to the rear hub.

Haven't tested it out yet

NISMO

Nice pics D,Do you know if the HPI forum is coming back up?

Distroey

The hpi forum is gone, they are switching to an all F.A.Q. based help system (frequently asked questions). The reason for this more then likely is that the forum was costing them too much in bandwidth per month. Oh yeah they are also going to have a chat room but that is dirt cheap.

Morpheus2be

Ok, I got my car just nice but with more understeer than I'm comfortable with. What setting should I use 1st? Softer springs or softer insert/compound? I've thought about putting some weights upfronts, but the Impulse is already heavy as it is.

Current setup, as per stock setup sheet. Using Sorex 36R/soft inserts rear and Sorex 40R/hard inserts front. Yellow stock springs all round. Serpent stock shock fluid allround....btw, I ruined the keyed shock pistons. Somehow, it drives better with no holes now.

InitialD

Using softer tires might give you the steering you want but at the expense of faster tire wear. Using softer springs would be better in this case since it's the front. Besides, it's cheaper to play with shock springs than it is to play with tire combinations.

Actually, what kind of understeer is this? On power or off power? You may want to look at settings elsewhere for your problem i.e. sway bar, droop, caster etc.

ammdrew

iTrader: (25)

try adding more rear droop, ie, if you are at 7 go to 6 that will give you more transfer to the front under braking, or slowing conditions and the car will turn faster, to the point it may feel loke the back end is loose....

PUNISHER

iTrader: (2)

Very good infomation guys!!

Morpheus2be

Well, the way I drive, I need on power steering. Off power, the front wheels hook up nicely. This is for the long sweeping corners. With the front one way, I brake just before going into the turn and immediately apply power for the fast corner. With the understeer, I've had to slow the car down (more than I like) to allow the front wheels to find traction. I was thinking of moving the front shock position to 2nd or outer most position to allow more front bodyroll.