Sprintex 335 Testing & Progress

[Ultramaroon]

Originally Posted by smudge

Be interesting to see how far you get before axles/drive shafts get broken!

What's been/going to be done about additional cooling? I assume intake temps are much higher than that of the 210 kit?

I'm getting around 29mpg (UK) average on my 210 kit, good to see the 335 isn't too much different unless you're thrashing it

4th gear will pop before anything else unless you're lowered, then it's a matter of time before you pop an outer cv joint on one of your half shafts.

The latter will happen with a stock engine but extra torque will hasten their demise.

[alexisfire02]

Intake temps were much much higher with the 335 kit than the 210. to the point that after 18 months of trying to lower the IATs of the 335, and 3 different tuners having worked on it for long periods of time, we abandonded the 335 and sold it.

We did go with a much larger water pump for it, which helped, but not enough to do 2 laps on a track before the ECU cut power.

[Xero-Limit]

Originally Posted by Ultramaroon

4th gear will pop before anything else unless you're lowered, then it's a matter of time before you pop an outer cv joint on one of your half shafts.

The latter will happen with a stock engine but extra torque will hasten their demise.

We had some of our STX auto-x competitors lose halfshafts on two different cars last year and the year before that. And that's on mostly ~ 200 whp cars, on 200 treadwear tires. With axles it is all about the tire and how much g-force you generate. The STX cars with modern 200 treadwears can pull well over 1g loading up the outside tire, and in 2nd gear that's a ton of torque even NA for that axle to handle.

[sam69]

I thought intake temps would be lower cause you can pump more air with less revs on the 335 compared to a 210 so maybe Mike can shed some light on this as I'm now

[Xero-Limit]

Originally Posted by sam69

I thought intake temps would be lower cause you can pump more air with less revs on the 335 compared to a 210 so maybe Mike can shed some light on this as I'm now

For a given boost the 335 will have cooler temps. So if you tried to spin the 210 to 14 psi with a 65mm pulley, the 335 will be way more effective at that. But 14 psi will be more heat than 11 psi no matter how you slice it. 11-12 is about where the 210 will top out.

[Ultramaroon]

Originally Posted by sam69

I thought intake temps would be lower cause you can pump more air with less revs on the 335 compared to a 210 so maybe Mike can shed some light on this as I'm now

The air temp is a function of the stored heat per unit volume. The size of the compressor doesn't have any effect.

Take 2 cubic feet of air at 70 degrees, compress it down to 1 cubic foot and the same amount of "heat" is still there. It expresses itself as increased temperature. The exact change is a function of some other stuff like relative humidity, etc...

[Xero-Limit]

Originally Posted by Ultramaroon

The air temp is a function of the stored heat per unit volume. The size of the compressor doesn't have any effect.

Take 2 cubic feet of air at 70 degrees, compress it down to 1 cubic foot and the same amount of "heat" is still there. It expresses itself as increased temperature. The exact change is a function of some other stuff like relative humidity, etc...

Don't forget adiabatic efficiency though. The 210 spinning too fast for its efficiency range will be less efficient than the 335 in its comfort zone. This is where the twin screw efficiency is a big plus over roots style.

[sam69]

Originally Posted by moto-mike

Don't forget adiabatic efficiency though. The 210 spinning too fast for its efficiency range will be less efficient than the 335 in its comfort zone. This is where the twin screw efficiency is a big plus over roots style.

So how come Alexisfire had so much trouble with intake temps to the point he took the 335 off ?

I know your 335 is going great but it's winter over there atm so wondering how it will go for summer

[Boofneenee]

Originally Posted by sam69

So how come Alexisfire had so much trouble with intake temps to the point he took the 335 off ?

I know your 335 is going great but it's winter over there atm so wondering how it will go for summer

Because Moto-mike?

[alexisfire02]

A big part was just that the 335 would not generate power. We tried going below 75 and 72 mm pulleys and that was just too fast for that blower.

(Even though according to the spec sheet we have for the 335 we weren't even approaching the max spin speeds.)


This blower is going to be for a very specific customer that doesn't need much whp, but is after the other benefits of a twin screw.

[sw20kosh]

Originally Posted by alexisfire02

A big part was just that the 335 would not generate power. We tried going below 75 and 72 mm pulleys and that was just too fast for that blower.

(Even though according to the spec sheet we have for the 335 we weren't even approaching the max spin speeds.)


This blower is going to be for a very specific customer that doesn't need much whp, but is after the other benefits of a twin screw.

This thing really seems to suffer on the top end.

[20firestorm13]

That's the nature of a twin screw in general. You get more instant down low but taper off on the top end. If you want more top end, you want a different type of SC or a Turbo.

[sam69]

Mike are you running a full exhaust system on your car now eg; header back or over pipe back and if so have you done any more dyno time to see how much it has gained ?

Also when do you think you will be getting off winter tyres ?

[Xero-Limit]

Originally Posted by sam69

Mike are you running a full exhaust system on your car now eg; header back or over pipe back and if so have you done any more dyno time to see how much it has gained ?

Also when do you think you will be getting off winter tyres ?

Has a full exhaust and header right now, but it won't go back on the dyno until spring and we have summers on. Header is a skunk2 unit but we may change that out.