As I'm sure most of us are aware of, we have seen a few sprintex'd members blowing pistons after fiddling with the tune. I have come up with a little theory about the cause, and conversations I've had with Sprintex and the NSW dealer (Tweakit) seem to comfirm it.

There has been speculation that leaning out/tidying up the AFRs to say 12:1 @WOT has been the cause of breakages, however I don't think this is correct.

Now due to the fact this setup is not intercooled, intake temps will go up dramatically in hot weather/hard driving. The sprintex program pulls ignition timing to prevent detonation, via monitoring of post-blower intake temps with a temp sensor. This feature is VITAL to keeping the motor detonation-free.

I believe people have been blowing pistons due to removing this feature by using new blank SMT6s without the Sprintex program, or using another blank piggyback ECU. Yes the same people have had their AFRs changed to say 12:1@WOT, but I think this is not the culprit.

What tuners usually do is advance ignition timing till it begins to detonate, then back it off a little. Problem is without intercooling in unusually hot scenarios the intake temps go up so much your motor will be suffering detonation, leading to a dead motor very quickly.

So by all means tidy up the AFRs if your tuner is able to edit the Sprintex program. But DO NOT let your tuner fiddle with the ignition timing, or use another ecu that doesn't have the Sprintex program with its ignition timing-retarding-with-temps feature.

I'm running the Sprintex program, but with the AFRs changed to 11.8-11.9:1 across the board @ WOT. After doing a torturous track day and a few months of road driving, it seems all is good with my motor. Sprintex seem to think even 12.5:1 across the board would be safe with their program. Though personally I'd prefer to to keep it at 12:1 just to keep combustion temps down a little, since you won't gain an awful lot of hp running it leaner anyway.

Of course it's certainly possible to run a custom tune that works safely with the Sprintex, but tread with extreme caution here, as the bottom line is many tuners probably don't have the patience/knowledge to make a safe tune for the sprintex setup from scratch.

Interesting theory. I haven't had any problems with my custom tune so far. I still need to take my car back to the tuner to smooth out the AFRs a bit but it's running much richer (safer) than the previous tune.

When it was really hot in the summer we just had i could definitely feel the heatsoak and the drop in performance that came with it. This is where the intercooler RPW is making should come in handy.

Would it be beneficial to get a retune if I installed the RPW intercooler? I guess you should see a few more kw out of the engine with an intercooler?

Interesting theory. I haven't had any problems with my custom tune so far. I still need to take my car back to the tuner to smooth out the AFRs a bit but it's running much richer (safer) than the previous tune.

When it was really hot in the summer we just had i could definitely feel the heatsoak and the drop in performance that came with it. This is where the intercooler RPW is making should come in handy.

Would it be beneficial to get a retune if I installed the RPW intercooler? I guess you should see a few more kw out of the engine with an intercooler?
You are right about the heatsoak. The sprintex ECU really robs you of performance the higher the temprature is.

Intercooler would definately be the way to go. BTW, is RPW making an intercooler for the sprintex kit??

You are right about the heatsoak. The sprintex ECU really robs you of performance the higher the temprature is.

Intercooler would definately be the way to go. BTW, is RPW making an intercooler for the sprintex kit??
Yes they are currently designing a water to air intercooler on tbb's supercharged Verada.

Yes they are currently designing a water to air intercooler on tbb's supercharged Verada.

Correct.

This will revolutionise the supercharged magna.

Here is the end game

1. Buy an awd magna for $15K

2. Convince Automotive Technology Group (the listed entity for sprintex) to build and install another of the finest positive displacment superchargers money can buy.

3. Go to the mitsubishi performance gurus and buy the well researched bolt-ons that myself and RPW are currently funding.

The result is a full sized four door sedan that leaves FPV and HSV on your rear view mirror for around $30k. Alternative: see how much it costs to get 500nM+ from an EVO that can tow a trailer in peak hour traffic and get 11L/100km on the highway.

Correct.

This will revolutionise the supercharged magna.

Here is the end game

1. Buy an awd magna for $15K

2. Convince Automotive Technology Group (the listed entity for sprintex) to build and install another of the finest positive displacment superchargers money can buy.

3. Go to the mitsubishi performance gurus and buy the well researched bolt-ons that myself and RPW are currently funding.

The result is a full sized four door sedan that leaves FPV and HSV on your rear view mirror for around $30k. Alternative: see how much it costs to get 500nM+ from an EVO that can tow a trailer in peak hour traffic and get 11L/100km on the highway.

how far away are we from this?

Would it be beneficial to get a retune if I installed the RPW intercooler? I guess you should see a few more kw out of the engine with an intercooler?

I imagine with an intercooler you would be able to safely run a little more ignition advance, due to the cooler intake charge (any idea how much RPW cooler is supposed to lower intake temps by?) But I'm not a tuner, best ask one :)


1. Buy an awd magna for $15K



Honestly, if you have a performance buildup in mind why would you buy an awd over a ralliart? Manual transmission and less weight (100kg+ from memory) is a hell alot more fun, and quicker too (except 0-60km/hr off the line, but it puts power down around a track just fine with the LSD).

Either way, a magna is never going to be a good bang-for-buck performance proposition. Not when for the same money you could buy an evo, s15 etc, and have access to an abundance of well-developed off-the-shelf bolt-on mods.

I mean I've loved every minute of what I've done, and still have plenty yet to do. But come on, if bang-for-buck was the priority, this car would have gone a long time ago. Although these days modding a magna is definantely getting cheaper and easier.


11L/100km on the highway.

That's nothing to brag about :p

Why so high anyway, I get 8-8.5L/100km on the highway with the sprintex, and it will probably improve with water/meth injection.

yeah on the highway my car beats that.

around town i get around 500km out of a tank

Chisholm, remember that I had the SMT6 in my car when it blew up, and it blew less than a week after Tweakit tuned it

I imagine with an intercooler you would be able to safely run a little more ignition advance, due to the cooler intake charge (any idea how much RPW cooler is supposed to lower intake temps by?) But I'm not a tuner, best ask one :)

We are expecting around 40 degrees temp reduction. Cooler air is more dense and contains more oxygen therfore more fuel can go in and with concomittant advances to timing more power can be generated . All i/c engines are disadvantaged by this lousy earth atmosphere to start with. Most of what you're compressing in the cylinder is inert nitrogen gas anyway.:nuts:

Honestly, if you have a performance buildup in mind why would you buy an awd over a ralliart? Manual transmission and ~150kg less weight is a hell alot more fun, and quicker too (except 0-60km/hr off the line, but it puts power down around a track just fine with the LSD).

The awd drivetrain is very strong and puts the power down just fine without losing rubber. 0-60 acceleration is 95% of what a daily driven street car does. When I was magna shopping I tried a ralliart and it was fun but I could not get a fast launch without breaking traction, which is the type of behaviour that gets a road registered car confiscated. I didn't buy a leather clad awd verada for track use. That's the next magna project which is unlikely to be street registrable

Either way, a magna is never going to be a good bang-for-buck performance proposition. Not when for the same money you could buy an evo, s15 etc, and have access to an abundance of well-developed off-the-shelf bolt-on mods. Also much greater access to a range of defect stickers and police impoundment yards:redface:

I mean I've loved every minute of what I've done, and still have plenty yet to do. But come on, if bang-for-buck was the priority, this car would have gone a long time ago. Although these days modding a magna is definantely getting cheaper and easier.



That's nothing to brag about :p

Why so high anyway, I get 8-8.5L/100km on the highway with the sprintex, and it will probably improve with water/meth injection.

Driving four wheels and extra weight hurts fuel consumption, but with the massive improvement in performance I have gained, I think 11L/100km on the highway is great, and that figure includes overtaking of road trains, caravans and commodores.

Chisholm, remember that I had the SMT6 in my car when it blew up, and it blew less than a week after Tweakit tuned it

when i was at tweakit they didnt have a dyno, are you sure they did the tune? they had to send mine away to their dodgy mates around the corner.

also tweakit kept my manifold, i added them to the list of guys ill never use again

when i was at tweakit they didnt have a dyno, are you sure they did the tune? they had to send mine away to their dodgy mates around the corner.

also tweakit kept my manifold, i added them to the list of guys ill never use again
no they dont have a dyno, they use the one down the street

Their dodgy mates around the corner are one of the best workshops in sydney. The do race prep for car which include old F1 cars, indy cars and so on. The workshop where the dyno is isnt dodgy, it comes down to who operates the dyno and that workshop just rent it out to whoever wants to use it (tweakit in this case)

i only considered them dodgy because theyre associated with tweakit, and they kept my manifold which is pretty dodgy.

i only remembered when i go home, i then rang them back and they denied it. if they werent so far away i would have went back.

Chisholm, remember that I had the SMT6 in my car when it blew up, and it blew less than a week after Tweakit tuned it

Wasn't that with a 10psi pulley and factory pistons? You have reason to believe Justin messed up the tune?



when i was at tweakit they didnt have a dyno, are you sure they did the tune? they had to send mine away to their dodgy mates around the corner.

also tweakit kept my manifold, i added them to the list of guys ill never use again

They use a dyno around the corner, seem to have some kind of sharing arrangement with the workshop that owns it. Justin from Tweakit does the tuning.

They gave mine back to me in a box, *shrug*.

Wasn't that with a 10psi pulley and factory pistons? You have reason to believe Justin messed up the tune?




They use a dyno around the corner, seem to have some kind of sharing arrangement with the workshop that owns it. Justin from Tweakit does the tuning.

They gave mine back to me in a box, *shrug*.

Yeah Jason did a good job on mine, covered just over 1000k's with the fresh tune and no issues whatsoever, but yeah should of heard Jason talk about your car TZABOY heh.

Wasn't that with a 10psi pulley and factory pistons? You have reason to believe Justin messed up the tune?

lol

Not knowing the full story, if this is true....then ahahahaha I've seen this so many times on so many forums 'this tuner killed my engine' then you find out its running X boost on stock parts.....

Yeah Jason did a good job on mine, covered just over 1000k's with the fresh tune and no issues whatsoever, but yeah should of heard Jason talk about your car TZABOY heh.
Justin and jeremy work own the place. What did they have to say???

Justin and jeremy work own the place. What did they have to say???

They were checking over my car, the Height etc and said "yeah this will go on no probs, better then the red thing, we have to run the hold downs through the bar and hope to god it doesnt move".

But there customer service is good, but its so far out from anywhere its crazy.

They were checking over my car, the Height etc and said "yeah this will go on no probs, better then the red thing, we have to run the hold downs through the bar and hope to god it doesnt move".

But there customer service is good, but its so far out from anywhere its crazy.
haha that wasnt my car they were talking about, that was the bowler's car. He's got a red VRX with that carmate front bar on. The front of my car has more clearence with the JVM bar than it had with the Ralliart bar