SPEED Tech

[Rockwood]

I would suspect they will have something? It’s been said that race teams running the Speed UTV will have some options that the consumer does not. Like removing the speed limiter. It’s been said the engine tuning is based around EPA standards. UTV race vehicles can remove those requirements and run richer, race fuels etc.. 

Yes the two tunes and E85 is measured by the same flex fuel sensors that GM is using. 

Also the Speed engine uses two injectors per cylinder. So while I don’t understand the whole system, I know the power is gained by not just increasing boost & running E85 but also the way the fuel is delivered. 

A little over a year or so ago when this was explained or realized, some of the factory UTV teams were starting to share their concerns with BITD & Score tech about how this might not be fair for the Production Turbo class. Both series allow aftermarket ECU tunes, but the injectors & turbos have to be factory production stock as delivered from the showroom. 

My assumption on 2 injectors is because injectors that support huge power/cylinder (like in the Speed's case) are hard to control at idle.  For a buggy, no big deal since no one's putting a sniffer on the tailpipe and no cat, so if it's a little "muddy", it just makes it sound cooler.  For something that needs to pass CARB inspection, 2 sets will let you get that big number with accurate fuel injection at low load.  

I haven't seen the compressor maps for the turbski, but looking at the dyno chart and how torque stays flat until redline at low boost, but dies off at high RPM on the big power tune, I'm assuming the turbo is running out of airflow at higher RPM.  Timing is almost never a problem at high rpm reliability wise, so I don't think there's much optimization left in the map.

 

[jginsandiego]

I would assume there is a flex fuel sensor.   

Yes but if you don’t have the speed fob and paid for the programming included with that it won’t matter anyway

It was explained in some of the past weekly shows and again in great detail at the sand show this year By Daniel the head engineer it will vary the horsepower at the top in between the normal key fob and the speed key fob maximum tune levels They also have quite a bit of safety margin with programming that will retard things as needed. They explained  that if you want to buy a special wire harness and put it in your own ECU that will be an option in due time.

 

[CampfiresNbrews]

Took a snap shot of this for those who plan on running E-85. GreaseMonkey had posted it somewhere, maybe the Speed thread I don’t remember. 
 

 

[Lord of the Dunes]

My assumption on 2 injectors is because injectors that support huge power/cylinder (like in the Speed's case) are hard to control at idle.  For a buggy, no big deal since no one's putting a sniffer on the tailpipe and no cat, so if it's a little "muddy", it just makes it sound cooler.  For something that needs to pass CARB inspection, 2 sets will let you get that big number with accurate fuel injection at low load.  

I haven't seen the compressor maps for the turbski, but looking at the dyno chart and how torque stays flat until redline at low boost, but dies off at high RPM on the big power tune, I'm assuming the turbo is running out of airflow at higher RPM.  Timing is almost never a problem at high rpm reliability wise, so I don't think there's much optimization left in the map.

From looking at the dyno chart, that seems like a reasonable analysis, I would come to the same conclusion.

However, in the initial FB post when they dyno tuned it, "Speed UTV" (somebody who works there) posted they hit 300 hp and 500 hp on 91 and (E85? race gas? I don't recall) so if the turbo was at it's limit, it couldn't have made that much power.

Would I swear to them making 500hp? No, since I didn't witness it myself. However I strongly suspect they're using the wastegate to control boost and power to detune it to provide only 230 and 300 hp for more reliability and to stick to the script. 

I would guess a tuner could make 350 hp or slightly more with pure ethanol or higher than E85. At this point, I can't prove it, but they've hinted at more power with this engine with just more tuning, so I'd tend to believe it.

 

[Sand Shark]

From looking at the dyno chart, that seems like a reasonable analysis, I would come to the same conclusion.

However, in the initial FB post when they dyno tuned it, "Speed UTV" (somebody who works there) posted they hit 300 hp and 500 hp on 91 and (E85? race gas? I don't recall) so if the turbo was at it's limit, it couldn't have made that much power.

Would I swear to them making 500hp? No, since I didn't witness it myself. However I strongly suspect they're using the wastegate to control boost and power to detune it to provide only 230 and 300 hp for more reliability and to stick to the script. 

I would guess a tuner could make 350 hp or slightly more with pure ethanol or higher than E85. At this point, I can't prove it, but they've hinted at more power with this engine with just more tuning, so I'd tend to believe it.

Getting more hp should not be a problem for a tuner.  The turbo on the Speed UTV is decent size that can handle more boost.   What were the stock boost number?  I do not recall the number, if they mentioned it.

 

[NIKAL]

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[NIKAL]

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[Rockwood]

Actually my understanding was that the car runs on one injector, and the second injector kicks in later. It was explained to me that with CARB and the emission standards set for the UTV category, that they only test the car with the primary injector. This was a huge advantage for Speed within the engine design and allowed them a broader range in the tuning and with the use of the second injector. 
 

I might be explaining it wrong, but I clearly understood that the CARB testing was done using only the primary injector. The vehicle/engine also has to go through a 10,000 KM test, which Speed did and has passed, along with all the other requirements. Speed also had another car that was at last years Sand Show, (all white carbon wrap) but has not been seen since. Todd was telling me several months ago how Speed is using that car to run their own long term durability testing and that car runs on a dyno just creating miles. He said they wanted to see 10,000 miles on that power/drivetrain. (I’m sure it was not seeing drastic loads and no drivetrain shock. But I like knowing the little engine can go 10,000 miles. 

We’re saying the same thing on the injectors. :biggrin:

 

[Rockwood]

Getting more hp should not be a problem for a tuner.  The turbo on the Speed UTV is decent size that can handle more boost.   What were the stock boost number?  I do not recall the number, if they mentioned it.

2 bar. It’s likely going into a shitty part of the compressor map where it’s making 1 part heat for every 1 part boost pressure

 

[CampfiresNbrews]

Watched video #58 last week and thought it was fascinating. The engine builder mentioned how a piston flexes and how they control the size of the port that expands the compression rings. Race part versus a production part. 

Topic that got me the most was at 20:10 talking about front wheel toe and tie rod placement. Robbie says in the front youre always striving to have toe out. Is that because its a 4 wheel drive vehicle? I know some front wheel drive cars purposely have toe out, because under load it goes back to neutral. I would have guessed a sxs had toe in like a quad or truck on the highway. 

@wopachop RG was referring to when the car lands a jump or hits an abrupt transition. The wheels always want to toe out. So if you have those tie rods placed on the rearward like many other mfgs do then you’re more likely to break them due to the fact your putting those rods in compression. Whereas when you put them in front like the Speed car, then they become in tension which makes them harder to break in half. That’s why he used a rope as an analogy. 
 

If you’re setting up your toe well then I’ve heard  anywhere from 1/8-1/4”  toe in for front and rear. 

 

[CampfiresNbrews]

While I understand your concern for the suspension mounted off the front dif. This is very strong and has been proven and tested not only on the Speed UTV, but on Robbys Trophy Truck and they have never had a suspension tab failure. I was told by someone with Speed that the engineered dynamic testing, live stress & load testing showed the tabs were stronger then the frame mounted tabs used on the XX, which were stronger then the tabs used on the RZR. Also each tab has a metal sleeve pressed in it, so at no time is the bolt rotating on the aluminum. But let’s say you were to damage a tab? The front dif is a 3 peace unit that you can buy & replace either side. This is much cheaper then a frame replacement or fabrication of a new chassis section.

Well said and here is a picture of the 3 piece bulkhead. Much cheaper to buy a section or the whole thing instead of a whole new chassis. And the tabs as was mentioned are pretty stout so it would take a serious hit to break one. And yes Joe public will do it. This thing is not idiot proof. I doubt myself or anyone here will break it. 
 


 

 

[ROBERT L]

I see what I think is a sway bar link in the picture. Does it have a rear sway bar? The reason I ask is the way it will 3-wheel in the corners on asphalt. I see the Speed Trucks do that also.  Is that the difference with having the trailing arms.  

 

[Rockwood]

I see what I think is a sway bar link in the picture. Does it have a rear sway bar? The reason I ask is the way it will 3-wheel in the corners on asphalt. I see the Speed Trucks do that also.  Is that the difference with having the trailing arms.  

I assume it's a couple of things: Robbie drives the Stadium Super Trucks, so it's his style to keep the power down like that and lift a front tire on asphalt, and trailing arm doesn't have any ability to dial out anti-squat with the suspension geometry (just spring rate, which has other requirements on an off-road vehicle), so the rearward weight transfer unloads the front tires.  Not sure if there is a rear sway bar (can't find any photos showing on on this thread).

But, did see this:

View attachment 12625

Which shows a nice (investment?) cast (stainless?) steel manifold.  Should last longer than the car.

 

[Sand Shark]

I see what I think is a sway bar link in the picture. Does it have a rear sway bar? The reason I ask is the way it will 3-wheel in the corners on asphalt. I see the Speed Trucks do that also.  Is that the difference with having the trailing arms.  

They have a rear swaybar.  If not the body roll would be a lot.

 

[SeanRitchie]

Regarding front diff/gear adjustments after changing out a damaged casting:

Professional opinion: check all adjustments and re-shim as needed. Don't count on absolute continuity of cast housings and machine tolerances. 

What I know will happen: Slap it back together and SEND IT! Just don't come complaining to me when your front R&P end up in a few hundred bits and pieces. I'll happily take your money to fix it properly. 

 

[NIKAL]

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[Sand Shark]

RG was saying after the NORRA race the brakes need to be changed to handle 35s.  Will he offer a bigger brake package as an upgrade or will he make the change in the production line?

Wonder what the issue was that he felt the car needed bigger brakes or a different brake set up with 35s.  

 

[Crusty]

I want to understand the Oil Return Line issue, I read that the line came off and dumped the oil. Was this a Race Car Feature or Production part / design? A good number of the Polaris Stop Rides were for exact same crap, huge cause of fires.

 

[ROBERT L]

I was hoping to get some kind of clarification on this also. 

 

[Sand Shark]

I want to understand the Oil Return Line issue, I read that the line came off and dumped the oil. Was this a Race Car Feature or Production part / design? A good number of the Polaris Stop Rides were for exact same crap, huge cause of fires.

I think the race car had a different style of attachment compared to the production cars.  It sounded like it was more due to poor prep and may not have been tightened.  

The guys that know all the details should chime in eventually.