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Does anyone know what size the stock injectors are in the Wildcat?
I will go over my notes from when we had mine flow tested. If they are the same part as the Prowler 1000 I might be able to help you but I don't know if they are. The Prowler 1000 injectors were maxed out when we dyno'd my XTZ. I ended up going with a much larger injector. I went larger then what i needed so we could run E85. I will look over my notes and see what I can find.
 

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I will call my Dyno guy Monday to verify but I think the stock injectors were about a 230cc injector. We went to a 550 cc injector. As we boosted fuel pressure the stock injectors couldn't keep up even at 10 psi of boost.
 

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22 lb/hr is 230cc. This puts the HP at 70. A bit undersized in my book if this is what's in the Wildcat.
That does seem small. We did boost the fuel pressure with the stock injector to 60psi and it put us at 100% duty cycle and that when we switched the injectors out. We dyno'd over a year ago so this is all from memory. I will check with the dyno guy on Monday to get some better info.
 

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That does seem small. We did boost the fuel pressure with the stock injector to 60psi and it put us at 100% duty cycle and that when we switched the injectors out. We dyno'd over a year ago so this is all from memory. I will check with the dyno guy on Monday to get some better info.
Here's your HP value's ......

230cc injectors -- 60 PSI rail pressure and driving them at 100% = 79 HP.
550cc injectors -- 43.5 PSI rail pressure and driving them at 80% = 128 HP.
 

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Curious ..... What was your static compression and Boost when you had yours Dyno'd -- And I'll take a stab at what your Dyno'd HP was .. .. :)
 

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Shoot I forget the compression but I think it's 10.5 to 1 and we ran 12 psi.
I plugged in some other variables to compute ........

Static compression of 10.5:1
951cc
12 PSI Boost
500' elevation
7000 RPM

Equates to appx. 140 HP at the crank.

Be curious to see what you actually Dyno'd -- And I like that Duno by the way .. .. Just wish we had one here in Havasu ........... Like to put my Turbo'd RzR Classic on it !!

:)
 

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I plugged in some other variables to compute ........

Static compression of 10.5:1
951cc
12 PSI Boost
500' elevation
7000 RPM

Equates to appx. 140 HP at the crank.

Be curious to see what you actually Dyno'd -- And I like that Duno by the way .. .. Just wish we had one here in Havasu ........... Like to put my Turbo'd RzR Classic on it !!

:)
Your calculations after being adjusted are not far off. This was one of the runs we made before the rear cv cage decided to exit the building!

The torque was impressive at 180 ft. lbs.
 

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Based on my estimated crankshaft HP of 140 and your Dyno run making 118 at the wheels equates to appx. 16% drive train loss.

My thought on the torque value at 3000 Rev's is -- The clutch is not locked and with the gear reduction at that low of an RPM and wheel speed - The torque value is unrealisticly high. Almost looks like the clutch at this RPM is a 3:1 gear reduction. This is just my very uneducated opinion though.

Have you had any engine trouble since you installed the Turbo and have you done any engine work before the Turbo installation ??

And for that matter - What is available for this engine ...... I do see that Speedwerx does offer a big bore kit for it ... .. I've not seen much else.

I know nothing about the Artic Cat V-Twin as to how reliable it is - Or how far it can be pushed.
 

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Can we put larger injector in with out using a turbo and will it help the power.
 

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Can we put larger injector in with out using a turbo and will it help the power.
No need for a larger injector unless you run forced induction. I am sure the factory injectors can flow enough if you stick to the NA motor even with mods. You can always add fuel pressure with an after market pressure regulator but it gets tricky. There is an internal pressure regulator on the fuel pump that you need to fool.
 

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Based on my estimated crankshaft HP of 140 and your Dyno run making 118 at the wheels equates to appx. 16% drive train loss.

My thought on the torque value at 3000 Rev's is -- The clutch is not locked and with the gear reduction at that low of an RPM and wheel speed - The torque value is unrealisticly high. Almost looks like the clutch at this RPM is a 3:1 gear reduction. This is just my very uneducated opinion though.

Have you had any engine trouble since you installed the Turbo and have you done any engine work before the Turbo installation ??




And for that matter - What is available for this engine ...... I do see that Speedwerx does offer a big bore kit for it ... .. I've not seen much else.

I know nothing about the Artic Cat V-Twin as to how reliable it is - Or how far it can be pushed.
That's the beauty of the CVT. It constantly changes the gear ratio. These torque numbers are accurate.

As for the motor. They are weak in a few areas and there are a lot of unknowns. They use a 3 piece crank that at least should be welded and trued if you want to run higher boost. They use an internal tranny and have had problems on Gen 1 and Gen 2 motor from the Prowler XTZ. Many guys have had the secondary trans failure and needed a new motor. They didn't have enough oil pressure in my opinion and there was insufficient oil flow to the secondary shaft components. They also had some faulty thrust washers that would break and go through the motor. This was happening to stock XTZ motors by the way. They made some major changes between the Gen 1,2 and 3 motors to improve the problem. The Wildcat from what I have heard uses the same motor that I have which is a Gen 3 and they improved on that a little as well. They removed a restrictor on the oil pump and changed the engine cases and the crank case venting drastically. I think these motor will run a long time if you don't run boost through them and if you keep it around 10 psi I believe you will have no problems. I wish someone would get into this motor and build it with the crank welded some pistons, rods, race cams, and titanium internals so we can get some more boost and rpm with out wondering what's going to happen. I gave a crank to Crankworks a long time ago for him to look at so call them if you have question about that. The main thing that I have not been able to do is find a fuel management system that works well with boost and is reliable. I am leaning towards the Gen 5 box from MCX turbo right now.
 

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Can we put larger injector in with out using a turbo and will it help the power.
Swapping injectors is as easy as changing the spark plugs - From a mechanical standpoint. The similiarities end here.

Yes -- The injectors can be swapped out without running a Turbo. I don't recommend doing this if this is all thats done.

And lastly -- Will an injector swap help the power. The short answer is no.

The engine does not use a closed loop EFI system. The manfacturer burns the various fuel maps into the ECM and depending on certain conditions a fuel map is activated in the ECM and this sends the injector pulse to the injector.

Now -- Immagine what happens when one swaps out the injectors. If one swaps larger flowing injectors in -- With an open loop EFI ..... The ECM sends the same injector pulse to fire the injector and with the larger flowing injectors -- The engine now runs rich and idles poorly. I have several video's on the Tube illustrating installing larger flowing injectors and how the engine responds - Or lack thereof.

If one swaps injectors -- It's important to also install a fuel box. One that can take away fuel as well as add fuel. It's also important to install a wide band A/F guage so one can program the fuel box so the engine will run in the proper A/F ratio.

One can also install a fuel box that will take the 02 sensor signal and will control the injector pulse so the engine operates at the designated A/F ratio that one programs into the fuel box. This fuel box takes the open loop EFI system and converts it to a hybrid closed loop EFI system. And yes -- Then an injector swap and using this type of fuel box has the potential to increase the engines HP.

:)
 
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