My Stretched Revo 5T conversion, advice pls - RC-Monster Forums

Overdriven · 12:49 AM

I've been wanting to do something like this for awhile, after seeing Lincpimp mention his savage I realized it wasn't that crazy after all. The chassis started as a 2.5, cut in half at tranny and extended 9.75in. E-revo tranny, and one looonnnggg rear driveshaft

I pulled my MMM 2200 and 5s 6000 polyquest from my buggy for testing, geared 18/68 it runs 140's @ 80 ambient, with plenty of juice to end up its roof. Funny site seeing this stretch limo riding the wing down the block.

My problem is the handling. The turning radius is pretty good, and in the dirt it'll slide pretty good. On the street, lifting the inside rear tire and eventually traction rolling is a problem. I'd like the rear to slide more, like my old 3.3 revo used to. Current setup is P1 rockers, springs are white front, green rear, inner hole on A-arms f+r, sway bars stiff front, soft rear. As far as I can tell the f-r weight distribution is about the same as an e-revo. I am going to change to stiffer springs f+r, and larger diameter tires, but am looking for suggestions on spring rates, tires, other settings. Getting it to handle is a must before buying a body.

And the pics

and a little size compatison with my slash bodied buggy

What's_nitro? · 12:58 AM

Welcome to the Monster!

The longer wheelbase will be more prone to rolling even with all else being the same. You could try lowering the ground clearance. That would help a lot. Maybe mount the battery lower, too. The only other advice I have for you is to keep doin' what you're doin' because it looks good!

Overdriven · 01:25 AM

Thanks for the welcome. Mounting the batt on either side would drop it 3/4", but totally ruin side to side balance to the point its visible. So I'd only do that if I got new batts or split the two 5s 6000 I have now. Not an option right now unfortunately, which is why I stretched this chassis with stuff I had around to make the batts fit. I'm up in the air on ride height atm, I need to go to my LHS for a body and tire fitting. This was supposed to a better vehicle for rougher offroad stuff than my buggy though, so the arms are a bit above bones level right now. Thanks for the suggestions.

What's_nitro? · 01:26 AM

Ehh it's not worth splitting up a pack. You could put it on one side, then put some weight on the other side. That might help with the wheelies too, if you want help with them...

Hey- just thought of this, but if you run some "smoother" tires in back they will slide better. Like step-pins or something.

Overdriven · 01:32 AM

During the planning stages I was actually thinking of running both my 5s packs in parallel for the runtime. But when I read more about how evenly they should be charged before connecting them together I decided against it. Would've been more hassle than its worth with my 610i. I might test mounting a pack on the side with some weight added to see what happens, I just don't like ADDING weight.

Chadworkz · 05.02.2009, 01:43 AM

For the rear, just add Tekno swaybars, and run the thickest bar...that will help a ton!

Also, you should try running a set of ½" off-set wheels, like JConcepts Rulux ½" off-set (17mm hex) or Pro-Line Velocity ½" off-set (23mm hex)...those will also help a ton!

transtalon · **stretch -** 05.02.2009, 01:57 AM

I did a 5" extended Lst2 but made a mistake on stretching the rear only like you did. What you should have done was to stretch the front and mount the battery on the added space and that will help a lot on wheely issue. On the Lst2 the shortened shocks works good, I'm not sure about the Revo. I made a 61mm front extended Lst2 and that was a lot better than the rear extended. I also made a flatpan Lst2 with a 2" front extended with a center diff. It handles real good and will just spins out and not rollover when you turn the steering while doing speed run. How heavy is your combo? I would try to lighten the chassis because even my setup it tend to spin out a lot due to the weight of the 8K MAH 6S lipo 15+ lbs. Goodluck.

squeeforever · 05.02.2009, 02:40 AM

Chad is right. Get the Tekno sway bars. The Traxxas actually do practically nothing. If you lift one wheel, the other should come up with it, but in the comparison I saw, the wheel didn't come up at all, even with the stiffest Traxxas swaybars.

BP-Revo · 05.02.2009, 03:46 AM

You'll want to stiffen your rear sway bar - a lot.

This will help prevent the inside rear tire from lifting and thus causing it to traction roll (this will also help it kick out so you can sort of drift it).

I'd also suggest P3 rockers. They help keep the truck from diving (transferring weight) too much in turns, which will help avoid traction rolling. It does not sacrifice handling in rough surfaces too much as long as you set the suspension up properly (ie, use the adjustment on the arms to lower the truck, not the pre-load).

I have most of my trucks this way - set up to just lose traction and slide rather than transfer weight and traction roll. As long as you are comfortable driving with the read end kicked out, it makes for a much more controllable vehcile, as rather than have it flip it just kind of slides out (and you can just control it to keep it going where you want it).

Just experiment with spring rates and pre-load and suspension height and you will find a happy medium. I spent about 10 hours of run time on the track tuning my G2R's suspension and I have it right where I want it. My diff unloads like crazy (and is actually toast, but I have V3 Hybrids from Mike ready to drop in). But right now I can drive it like a crazy person and unless I'm on the street, and at its limit the back end will just kick out if I'm under hard accelleration, or if I'm braking or coasting the truck will just slide as whole. All I have to do is make some steering correction and even if the truck looks like its out of control, its actually going in the direction I want it to.

Overdriven · 01:50 PM

Thanks for the input everyone, keep the questions and comments coming. I knew I'd have to get my stiff sway bar back from a friend, but I didn't know the Tekno was that much better. Being on a budget (see my buggy thread http://www.rc-monster.com/forum/show...998#post283998 ) I'll try the stiff traxxas for now and move the links down as far as I can. If you lift one rear wheel the other will come up, but only when the one being lifted is almost at the end of its travel. P3 Rockers require longer pushrods right?

I'm thinking some tan springs for the rear and move the greens to the front. The truck weighs 12-12.5lb with batt right now, and sags a little too much. The handling is pretty neutral on dirt and can be made to slide easily, but I need a little slide action for tighter turns on the street. I don't want a one trick pony. I'm going to try moving the batt forward a bit too. Not to prevent wheelies as they only happen from slow speeds or a stop.

I know wider offset wheels will help alot, but they won't fit under the body, and I don't have any right now. I'm going to do some test fitting at the LHS today, I'll see if they will rub and what it looks like. I'll be taking pics too, vids will come when it stops raining here.

Hey Lincpimp, how's your savage coming? Can't wait to see another one of these going.

lincpimp · 05.10.2009, 03:23 AM

Quote:

Originally Posted by Overdriven

Hey Lincpimp, how's your savage coming? Can't wait to see another one of these going.

Just noticed this...

I like the idea, and I was planning to section 2 revo chassis together to get a stretched chassis for another of my larger scale builds. I do not need as much wheelbase as you do... I also have tons of revo parts, and the track width with 0 offset wheels is just about right to match up!

I am still working on the shorter 15" WB savage, and got all of the stuff in/ordered to do the 5t sized savage. I still need to finish the baja 5b conversion too. I seem to have alot of custom projects now!

If you look on ebay someone is selling "seconds" of the proline desert rat conversion corr body for the 5b for right at 100 bucks shipped. Pretty good deal considering they sell for 135 plus shipping. He says there is only 1 blem on the body? Maybe something to look into, I would have bought one, but I already have my desert rat body.

Overdriven · 02:17 PM

Quote:

Originally Posted by lincpimp

Just noticed this...

I like the idea, and I was planning to section 2 revo chassis together to get a stretched chassis for another of my larger scale builds. I do not need as much wheelbase as you do... I also have tons of revo parts, and the track width with 0 offset wheels is just about right to match up!

I was in the same boat, working with what I had around. I've spent to much $ in my nitro days, trying not to repeat that. If I had or knew someone to weld alum, I would've done something more like a sectioning job. Would've been more work measuring, bending, cutting and cursing, but would look much better. I mention the cursing because the easiest place to section is in the trans area, and that still has alot of curves, so I wish you luck with that

And yes, zero offset wheels fit under the 5t body just like a stock 5t does. The RPM wide offsets don't, but with the body at the height I have in the pics, they don't rub when the suspension is fully compressed and it still looks good from the front and the sides at ride height.

Quote:

Originally Posted by lincpimp

I am still working on the shorter 15" WB savage, and got all of the stuff in/ordered to do the 5t sized savage. I still need to finish the baja 5b conversion too. I seem to have alot of custom projects now!

And we keep hearing about them, but never see them finished! J/K I know how it is to be r/c crazy with 3 or 4 vehicles in pieces, while you run the other 2. I'm glad I'm down to 2 now. I almost went shorter, as MCD has a trophy style truck, and VSModelsport makes/used to make? a similar body for MCD/FG vehicles which are a few inches shorter. But considering the cost of the bodies being about equal and having never seen one in person and having no way to do mockup I went 5t wheelbase. The pics shown are the 1st mockup with the new chassis, but I've done others with stock length to check the body height, width etc before even getting started, so it was mostly a convenience decision.

Quote:

Originally Posted by lincpimp

If you look on ebay someone is selling "seconds" of the proline desert rat conversion corr body for the 5b for right at 100 bucks shipped. Pretty good deal considering they sell for 135 plus shipping. He says there is only 1 blem on the body? Maybe something to look into, I would have bought one, but I already have my desert rat body

I'm not a fan of the desert rat for the 5b, the top of the wheelwells is too thin in profile and doesn't look right to me. Thanks for the tip though, I'll look into it. I'm up in the air at the moment with this project. I'm going to try a few more things to get it to handle better on the street as this is my primary running surface. I think my main problem is my buggy is too much fun to drive. I drive it like I stole it and it just comes back for more, well more tires anyway! If I could convince myself its worth it to buy another esc+motor for a truck I won't run as often I'd be happy with it as is.

Overdriven · 05:47 PM

Well I just got back from the LHS. I got to try some LST/aftershock tires on RPM wide offset rims and they don't rub and look good, so wide offset it is. Any other tall (~7in) tires out there besides the LST and HPI Terra Pins that'll fit a 14mm or 17mm rim? I have the 17mm and don't want to shell out for 23mm adapters and I don't want a dish rim either. Ideas are welcome. Here's some teaser shots.

BL_RV0 · 05.02.2009, 05:48 PM

You could try some 40 series 17mm wabash rims on moab XLs.

Overdriven · 05.02.2009, 11:38 PM

The wabash series are no longer on the proline site, and tower only has them in buggy size. Somebody probably has a set lying around. But the Moab XL's would be a perfect fit for the Jconcept Relux Halfups in 1/2 offset. I think thats the route I'll go, but I wouldn't mind hearing other ideas.

I installed black springs in the rear now, with the greens up front. Got the thick rear sway bar in with the links lowered on the bar. The weather should break Sunday so I'll have another test run and try to get a vid.