GRP compound for speed runs

[SrC]

I want to get some GRP 1/8 slicks for speed runs. Not sure what compound would be better suited for it.

My thinking is softer for more grip but not sure if softer is right at speeds.

Info:
It's cold (9-18C) here atm and the road surface is coarse asphult but level. Running the Typhon 4x4 on 4s and choons but may go 6s soon. I'm only newish to speed, currently at 81mph, aiming for 100mph at the moment. Not sure how much more the choons can handle. (Anyone gone faster with choons?)

A know foams would be a better option but BSR and Gone Bananas are pricey here.

I've got the GRP compound chart but still not sure. What do you recommend?

Trial and error what works for you. Try a middle compound to start. And what works on one rig for someone else, won't necessarily work on others or for you. Too many variables to consider, not just the compound. If you drive fairly well, you can adapt to whatever compound. But in general Compounds equate to the Temp of pavement surface you have. Not a hard rule however IMHO. Just as a guide.
Foams are a waste, very shortlived, and only needed for 140'ish -200+ MPH serious speed runs. Common to only get several good hard passes with Foams at those high speeds. They will start to chunk out fast. Been there.
Keep pushing the Choons for now. Legit Hoons are generally good for 120 to 130, so they say. If they are not abused/ bashed/drifted on hard. I never heard of any serious complaints with the Choons at Sub Triple digit speeds. Should handle your 100mph target PB.
Definitley go with some GRP's, to experiment with at some point. The popular brand these days.

 

[Warby]

Trial and error what works for you. Try a middle compound to start. And what works on one rig for someone else, won't necessarily work on others or for you. Too many variables to consider, not just the compound. If you drive fairly well, you can adapt to whatever compound. But in general Compounds equate to the Temp of pavement surface you have. Not a hard rule however IMHO. Just as a guide.
Foams are a waste, very shortlived, and only needed for 140'ish -200+ MPH serious speed runs. Common to only get several good hard passes with Foams at those high speeds. They will start to chunk out fast. Been there.
Keep pushing the Choons for now. Legit Hoons are generally good for 120 to 130, so they say. If they are not abused/ bashed/drifted on hard. I never heard of any serious complaints with the Choons at Sub Triple digit speeds. Should handle your 100mph target PB.
Definitley go with some GRP's, to experiment with at some point. The popular brand these days.

Thanks. Yes I'll push the choons to there limits. 96mph so far but 130 you say, wow. They seem to grip well so far. I did a couple of passes with my old, beaten GRP Revo's but they didn't seem to have as much grip and are out of balance. I have some new GTJ T04 XM3 slicks on order so will give them a go later.

 

[Warby]

The GTJ T04 XM3 slicks arrived. Being that they are the GTJ, the inner rim bead is slightly thicker, but the hex actually had less thickness and support. But only by 1mm.

 

[Warby]

@K-BASH @chris adams What wt oil should I run in the 4x4 diffs for speed runs? It still has the stock oils and I'm noticed it's pulling to one side under power, with the current power system. Just ran it up my street to test. I have just fitted the 4282 2150kv motor.

 

[K-BASH]

@K-BASH @chris adams What wt oil should I run in the 4x4 diffs for speed runs? It still has the stock oils and I'm noticed it's pulling to one side under power, with the current power system. Just ran it up my street to test. I have just fitted the 4282 2150kv motor.

I use 20 million traxxas fluid or these in all my diffs

 

[Warby]

I use 20 million traxxas fluid or these in all my diffs

View attachment 309816

Ok so you almost fully lock them. I do have those wax ear plugs on hand. Only in the rear diff?

 

[K-BASH]

Ok so you almost fully lock them. I do have those wax ear plugs on hand. Only in the rear diff?

On mine rear is locked with metal diff,front is not as locked with plastic diff

 

[Warby]

I'm so thrilled. It seems my stars were aligned today. The weather is perfect, my son and I both had some free time, so we took the Typhon to our speed run road and to our surprise, they've resurfaced it with that fine hot mix asphult. It's like a runway now.

I was a little nervous as I have made quite a few changes to the Typhon since the last run, so I wasn't sure what to expect.

Changes:
New GRP's slicks, 4282 2150kv motor, bigger pinion(32t I think ), different front splitter, R7FG RX, wheel alignment and thicker diff oils.

Anyway, it drove like a champ. Straight as an arrow. Minimal steering input required. The GRP's never lost traction, even with hard braking and no ballooning. The handling didn't change at speeds. No cogging and motor temps stayed reasonable so can go a bigger pinion.
I'm very happy with it.

And to top it off, not only did I beat my PB, but I also reached my first goal of 100mph.

102mph (164kph) on 6s

What should my next target be?

 

[SixD9R]

New pb. 96mph (154kph) on 6s. So close, I can almost smell 100mph. Haven’t reached full throttle yet. Ran out of time and unfortunately I won't get another chance to run it for over a week.
And still on the choons. So exciting.
View attachment 305558

Run your 3200kv on 6s. I guarantee 1000+ MPH

Run your 3200kv on 6s. I guarantee 1000+ MPH

I mean 100MPH+

 

[Warby]

It's getting a bit crowded in here

 

[Tex Koder]

It's getting a bit crowded in here

View attachment 319914

You need a chassis spacer

 

[Warby]

You need a chassis spacer

Or a XLWB. I am considering it.

 

[SrC]

Go super slow and smooth on the trigger. Focus on only using a steady squeeze and don't worry about how much trigger is left. Let it be a surprise when it bottoms out. That'll keep the amps low stop if from cutting.

+1
Always make sure ESC PUNCH is dropped all the way down. With Speed running. This lessens greatly, the chance of premature Amp cutting.

 

[Warby]

Gained 3mph with the new CNHL 6200mAh lipo today. My PB is slowly climbing. 105mph but I was fighting 69km/h gusts, blowing across the road so I only did 1 run and didn't hold full throttle for long. Wasn't worth the risk.

 

[SrC]

Good to know when to stop passes if it's windy. Will ruin a wet dream if you get greedy and keep going. Speed running carnage is costly. Wind can lift a rig and send it like a frisbee. I know. Especially Cross and Head winds.
A Tail wind can help with top speed. Is that cheating?? IDK.

 

[Warby]

Good to know when to stop passes if it's windy. Will ruin a wet dream if you get greedy and keep going. Speed running carnage is costly. Wind can lift a rig and send it like a frisbee. I know. Especially Cross and Head winds.
A Tail wind can help with top speed. Is that cheating?? IDK.

Yes I didn't want to risk it, especially with that new 6200 brick. I had mental images the brick getting flung out and rolling down the road like something from a Raz Shifrin video. Although the winds didn't seem to phase the Typhon too much. The Infraction use to be pushed around a lot more by winds. One of the reasons I abandoned that project.

Wish it was a tail wind. They were definitely cross winds, blowing damn sticks and leaves across the road. Had to keep picking them up.

 

[SrC]

That nice looking Infraction body, unfortunatley sucks with Areo. I placed a flat piece of Alu on the rear bed's roll bar, and it worked out great. Looks like a fast back flatter rear. A bit more stability. The Infraction body shape eats up alot of amps in general. Best for just hooning around.

 

[Warby]

34t just fits. Had to elongate the adjustment holes a little more and also shave a small amount of plastic of the housing.