Wr8 3.0 2 speed
 

Are there any opinions for a 2 speed tranny for the hpi wr8 nitro car?
I sold my old rs4 rally to by a newer car and I don't like the idea of being stuck with a single speed trans.
I can see it being better off road with the single speed. But on road a 2 speed seems like a better idea.

Would a 2 speed out of a rs4 fit? I'm guessing if it does it will need bigger barrings.


Any idea or opinions here?


Edit:
I don't mind if I have to do some modding to get a 2 speed to work.

Re: Wr8 3.0 2 speed
 

no idea man... I hope someone here can help out

Re: Wr8 3.0 2 speed
 

The bearings are the same size, 10x15, but the width of them may not be the same. I have sold my 2 speeds from the rs4 mt2, so no help there.

Re: Wr8 3.0 2 speed
 

Yeah I did some looking, they use the same bearings. And looks the the cup joints are both 5mm. So long as the tarns is not shorter or longer it would work!
I have an rs4 with a 2 speed and just ordered a wr8 so I'll find out and report back.

In fact I found a older NOS Abu Dhabi wr8 for 300$ With a nitro starter kit. At that price I don't care if I can't used a 2 speed.

Re: Wr8 3.0 2 speed
 

I tried putting an rs4 2 speed in my wr8. It almost fits, but I'll have to use a different size drive shaft as the rs4 trany is abit longer. I bet I could cut it down to fit if need be.
But i think I might get a big block for it and wider gearing, I really like the center diff.

Re: Wr8 3.0 2 speed
 

Hi there.

I bought my hpi wr8 second hand about 6 months ago.
Love it! I’ve had loads of hpi cars over the years and this one I think is my favourite.

Picked this car out of a bunch of cars bundled together on a Ebay listing. Messaged the guy and asked if I could buy just this one.

Here she is as pictured in Ebay.

https://uploads.tapatalk-cdn.com/201...8b5e37219b.jpg

Randomly had a set on firestorm wheels on it (which do not do the car any favours. Dramatically reduced handling)

So I’ve ran a fair few tanks through it and it’s great. I’ve upgraded a few parts already with alloy.

But it’s a 2 speed transmission I want. I checked out the old internet and seems no one has done it. But yo guys where talking about it and I thought I’d share my experience of retro fitting a hpi rs4 3 (2speed transmission) to a hpi wr8

So I went down the down the route of buying a rs4 as a donor car. Ebay again

https://uploads.tapatalk-cdn.com/201...d2753eae2d.jpg

Now I wanted to do this mod without any major changes to the parts of components of my wr8. So any modding I do is mostly on the rs4 parts.

Here’s the two side by side.

https://uploads.tapatalk-cdn.com/201...2be7dbb893.jpg

I stripped out both centre diffs and started taking a look at how I was going to do it.

https://uploads.tapatalk-cdn.com/201...60b7ab0533.jpg

https://uploads.tapatalk-cdn.com/201...9e21e7f933.jpg

https://uploads.tapatalk-cdn.com/201...4979a936e8.jpg





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Re: Wr8 3.0 2 speed
 

This is not a simple swap parts out and in.
But I’m here now and I think the effort should be worth it.

Turns out that you can’t just bolt the rs4 box straight in. It’s about 10mm too long and the diff cases don’t fit in with the tank and receiver box.

I don’t want to drill holes in the chassis if I can help it to relocate.

So I started building the 2speed with the wr8s centre diff mounts.

https://uploads.tapatalk-cdn.com/201...2433584fd7.jpg

There’s a spacer/reducer that needs to be milled down by about 5mm to bring the two out diff supports down to original size.

Also the diff shaft is two long and the diff cups are not going to work either.

I bought new diff cups

https://uploads.tapatalk-cdn.com/201...c1a7b8a58d.jpg

I have the space in the tool shop being milled down and I’m waiting to collect it on Monday.

So that’s as far as a can get wit the centre diff for the moment.


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Re: Wr8 3.0 2 speed
 

I fitted the diff roughly into the car to see how far off the centre diff shafts are going to line up.

With the new diff cups I bough and after nodding the diff shaft it should be ok.

https://uploads.tapatalk-cdn.com/201...12c8420443.jpg

https://uploads.tapatalk-cdn.com/201...aca855440c.jpg

Then I loosely put the 2speed clutch bell on the wr8 engine and see how she fits.

https://uploads.tapatalk-cdn.com/201...e0cf182ec9.jpg

As you can see it meshes fairly good.


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Re: Wr8 3.0 2 speed
 

One thing I have noticed is that the chassis will need to be modified.

Both the flywheel and the second spur gear are catching the chassis very slightly

I mark it out and hit it with a dremel later on.

https://uploads.tapatalk-cdn.com/201...62604e75dc.jpg

https://uploads.tapatalk-cdn.com/201...a0b6dfd392.jpg

https://uploads.tapatalk-cdn.com/201...8df5f55806.jpg

I’ve been working in the clutch bell system and adding it onto the original g3.0 wr8 engine.

See the 2 speeds are fitted to the T3.0 engine not the G3.0. The engine shaft is not threaded the full length on the G series.

T3.0

https://uploads.tapatalk-cdn.com/201...99248e191e.jpg

G3.0

https://uploads.tapatalk-cdn.com/201...efed69e185.jpg

The t3.0 and the rs5 t.15 engine both share the same shaft design and the clutch bell is held in place using one of these.

https://uploads.tapatalk-cdn.com/201...dbfac8aea4.jpg

This is a pilot shaft.

The other issue is the shaft lengths are the same on both engines but the t3.0 having a threaded shaft can be extended using the pilot shaft as pictured about.

So my engine the g3.0 needed some modding. I really didn’t want to do anything to permanent.

I did try and put a thread on the end of the shaft but it’s hardened steel and it just wasn’t going to work.

So I used the pilot shaft from the rs4. I cut the smooth shaft part away from the body.

Almost right on the joint line between shaft and body.

This is the same diameter as the g3.0 engine shaft and it’s threaded all the way through.

So I built the clutch up using this to extend the shaft and voila. I have a g3.0 fitted with a fully working 2speed clutch bell.

You will need to shave the clutch shoes top edge as the clutch basket is slights lower than the wr8s clutch.

https://uploads.tapatalk-cdn.com/201...0d3ef0f60b.jpg

https://uploads.tapatalk-cdn.com/201...4528bd64c0.jpg

I also replaced the pinion gears. Not a fan of pink and they where pretty worn out too.

Orange is better.




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Re: Wr8 3.0 2 speed
 

Nice work! I still have 2 old HPI Super Nitro Rally's, kinda the predecessor to the WR8. Still great cars! One has the 2 speed/nitro engine, and the other was converted to electric.

Re: Wr8 3.0 2 speed
 

Sweet.

I’m still in the process of doing this. I’m gunna do a little more tonight and through the week.
I’d like to have it done by next weekend so I can take it out and set the gear change up how I want.

I’ll put a vid up of it soon. Hopefully all up and working as should.

It’s defo not a hard mod to do but there’s a lot of work to do.
Can’t wait to hear her fling into second tho.



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