Hello everyone. I was just thinking of starting a project to supercharge my car(manual TJ magna sports). I have been searching old threads and have come across a lot of posts that mention that the magna ECU cannot handle any boost. Now the question to members who have already tried to do this is, what exactly happens?? detonation?? fuel cut?? now i need facts from members who have tried this before not just assumptions.

now considering that the magna is designed for fuel that is 90RON, When you boost it using a positive displacement supercharger which has constant boost accross the rev range(e.g roots type) and you use more than 98RON fuel, will this avoid detonation at boost as low as 4-6 psi??

Can the magna ECU handle fuel delivery? If the Air flow meter is placed before the supercharger so that it correctly measures air(uncompressed), the ECU should be able to handle correct fuel delivery(considering fuel pump and injectors can supply that amount), right ? The sprintex setup has one extra injector to enrich the fuel and also cool the supercharger so as to prevent detonation but is this necessary if intercooling or water/methanol injection is used instead?

I am assumming the sprintex piggyback(smt6) intercepts the crank angle signal to control spark advancing/retarding. I think that the spark is retarded by an additional particular constant angle throughout the rev range(because boost is constant throughout the rev range) in addition to the ignition map in the ECU. is that correct?

any enlightenment of the topic is highly appreciated.

interesting questions...

basically all the supercharger kits available to you.. well there is really only 2 now.. Raptor and the bullet kit like mine, same type of supercharger. just different types of setups, I think mine looks better and its proven to make a little bit more power :P however raptor haven't got a intercooled version on the road yet..

each kit comes with its own type of ecu, again, all pretty much do the same thing.

DO NOT attempt any kind of forced induction without planning to install a piggyback.. the booster injector is really just in place avoid upgrading all 6 injectors as oversized injectors were not always readily availiable to us. now raptor have found some the use of the booster/7th injector is not really used for much, but is handy to have there when needed.

i didn't really answer your questions. but basically just stick to what is proven to work. STM6 is great but can be limited unless you buy an unlocked one. XEDE seem to be great, I have one, morishtec (Spelling) provided by raptor seems to be great aswell and when you buy the raptor kit they give you a base tune which will allow u to drive the car straight away ofcourse for optimum gains you will get another tune done to suit your car.

Hello everyone. I was just thinking of starting a project to supercharge my car(manual TJ magna sports). I have been searching old threads and have come across a lot of posts that mention that the magna ECU cannot handle any boost. Now the question to members who have already tried to do this is, what exactly happens?? detonation?? fuel cut?? now i need facts from members who have tried this before not just assumptions.

now considering that the magna is designed for fuel that is 90RON, When you boost it using a positive displacement supercharger which has constant boost accross the rev range(e.g roots type) and you use more than 98RON fuel, will this avoid detonation at boost as low as 4-6 psi??

Can the magna ECU handle fuel delivery? If the Air flow meter is placed before the supercharger so that it correctly measures air(uncompressed), the ECU should be able to handle correct fuel delivery(considering fuel pump and injectors can supply that amount), right ? The sprintex setup has one extra injector to enrich the fuel and also cool the supercharger so as to prevent detonation but is this necessary if intercooling or water/methanol injection is used instead?

I am assumming the sprintex piggyback(smt6) intercepts the crank angle signal to control spark advancing/retarding. I think that the spark is retarded by an additional particular constant angle throughout the rev range(because boost is constant throughout the rev range) in addition to the ignition map in the ECU. is that correct?

any enlightenment of the topic is highly appreciated.

Stock ecu: poor/scary fueling, but mostly timing is way off. LOTS of timing needs to come out at boost. DO NOT DO IT. The same reason a NA Lancer doesn't become an EVO by adding a turbo and nothing else.

IMHO Water/Meth will kill the Sprintex charger - people barking up this tree expecting big things will get something big: a 'bang'. The Sprintex kit was a good stepping stone as it got the ball rolling for Magna FI, despite several turbo installs prior there have been very few if any turbo installs since the Sprintex kit rollout and Raptor SC availability.

The ECU will hit a mapping ceiling in that there will be so much air being drawn thru that the injectors will be at peak duty cycle at say 5psi and 4500rpm when there is still a lot more boost and rpm to be covered yet.

The stock ecu wont be able to control an injector upgrade for the application except *maybe* when cruising.

The Moristech Pro Sequential intercepts the crank angle sensor output to the ECU to control spark timing and does it well. I can't recall what the SMT6 did. Many interceptors try to alter the air temp and water temp sensor signals to induce timing changes. AVOID these as they are not precise enough and will cause bad things to happen AND cost you power, driveability and fuel economy will suffer too.

Check out the Raptor threads in the sponsors section on AMC (bottom of main page) for additional info. :cool:

Hello everyone. I was just thinking of starting a project to supercharge my car(manual TJ magna sports). I have been searching old threads and have come across a lot of posts that mention that the magna ECU cannot handle any boost. Now the question to members who have already tried to do this is, what exactly happens?? detonation?? fuel cut?? now i need facts from members who have tried this before not just assumptions.

now considering that the magna is designed for fuel that is 90RON, When you boost it using a positive displacement supercharger which has constant boost accross the rev range(e.g roots type) and you use more than 98RON fuel, will this avoid detonation at boost as low as 4-6 psi??

Can the magna ECU handle fuel delivery? If the Air flow meter is placed before the supercharger so that it correctly measures air(uncompressed), the ECU should be able to handle correct fuel delivery(considering fuel pump and injectors can supply that amount), right ? The sprintex setup has one extra injector to enrich the fuel and also cool the supercharger so as to prevent detonation but is this necessary if intercooling or water/methanol injection is used instead?

I am assumming the sprintex piggyback(smt6) intercepts the crank angle signal to control spark advancing/retarding. I think that the spark is retarded by an additional particular constant angle throughout the rev range(because boost is constant throughout the rev range) in addition to the ignition map in the ECU. is that correct?

any enlightenment of the topic is highly appreciated.

Above posts is right, also the stock ECU lacks a MAP input which is the ability to measure the psi of the manifold during the rpm cycle.

With the sprintex you can only go the SMT6. Whys that people ask? the Reason being, it has a failsafe built into the ecu to pull timing when it reaches a certain temp to prevent detonation and breaking off the first ring land.

Now i do own a sprintex'ed magna, unmolested it runs fine (making 162atw with auto and stock zorst) havent played with anything else and have done over 35k with no issue (until last week but it might of been a ghost). A lot of guys on here bag out the sprintex but they did one thing that raptor and Rotex, which was prove a decent, not overly expensive supercharger option for the magna and only have a 2 day turn around on the product installation.

Also twin screw doesnt have boost from idle, it makes serious boost from about 2000rpm onward when under load (might make some but my gauge doesnt pick it up stays at zero not at vac or anything)

The 7th Injector (as much as the trolls on here reckon its anarchic) was a good cost cutting job, however it does do the job of sealing the blower and providing the additional fuel needed, its a 250CC unit but according to Jason at tweakit it only ever runs at about 40% duty cycle at full acceleration as its just an aid.

And Ian even sprintex said a water/meth kit is fine for it, they arent coated rotors like commodores in which the water can erode them, they are anodized. Ive got a very very basic one i was using recently (consisting of a 80cc injector off one of those pocket rockets, 2x windscreen washer pumps a reservoir and was piped just before the elbow in the factory piping, i did notice a difference mainly on hot days as it wouldnt go as limp as it normally would, but only a series of back to back dynos will be able to tell you how much you can potentially get out of it

IMHO Water/Meth will kill the Sprintex charger - people barking up this tree expecting big things will get something big: a 'bang'. The Sprintex kit was a good stepping stone as it got the ball rolling for Magna FI, despite several turbo installs prior there have been very few if any turbo installs since the Sprintex kit rollout and Raptor SC availability.

The ECU will hit a mapping ceiling in that there will be so much air being drawn thru that the injectors will be at peak duty cycle at say 5psi and 4500rpm when there is still a lot more boost and rpm to be covered yet.

The stock ecu wont be able to control an injector upgrade for the application except *maybe* when cruising.

The Moristech Pro Sequential intercepts the crank angle sensor output to the ECU to control spark timing and does it well. I can't recall what the SMT6 did. Many interceptors try to alter the air temp and water temp sensor signals to induce timing changes. AVOID these as they are not precise enough and will cause bad things to happen AND cost you power, driveability and fuel economy will suffer too.

Check out the Raptor threads in the sponsors section on AMC (bottom of main page) for additional info. :cool:

AFAIK there's no evidence whatsoever to suggest water/meth will kill the Lysholm blower Sprintex use. Please enlighten me if you know something I don't!

If you use a crap kit that's not atomising properly and dumping huge droplets of fluid into the intake tract, then yes you will probably get pitting/damage on the rotors. A long as the water/meth is atomised properly, there shouldn't be a problem. Seeing as how the Sprintex blower deals with the fuel from the 7th injector being sprayed into it just fine, what makes you think it would be different with water/meth?

I've been told by numerous sources to expect roughly a 10-15% gain across the revrange in power with the use of a properly implemented water/meth setup, coupled with a suitable retune (i.e ignition timing advanced, and the fueling needs to be trimmed if you are using meth). Of course in hot weather the gain would probably be bigger, as the Sprintex won't be switching to the 'retarded' map like it normally would.

I don't see why hitting a mapping ceiling would be an issue, seeing as how there are examples of magnas around putting out good numbers with either a remapped factory ECU (jasonsVRX), or factory ECU + piggyback (RPW TT magna). Never heard of anyone hitting a mapping ceiling on a magna ECU. Once again, if you know something I don't, please share :)

Just about any basic piggyback intercepts the CAS signal to control timing. Since you bring it up, can you name one that doesn't? You've got me curious, I wasn't even aware ANY piggybacks use the method you described to control timing.

In short I don't see any point to go to a replacement ECU. Just about any decent piggyback when correctly tuned can handle a mild boost application for a magna just fine, there's nothing tricky about it at all. Of course theoretically a replacement ECU can give a better result due to have higher resolution maps, but in practice I'm not convinced there would be a tangible benefit.

I don't have any experience with the Moristech, but IMO any decent piggyback can do the job just fine. Your choice if ECU (both piggyback or repalcement) should be mainly determined by what the tuner you are using is the most experienced/comfortable with. E.g no point in getting a Haltech if your tuner hasn't played around with them much, but is experienced with someone else that'll do the job.


With the sprintex you can only go the SMT6. Whys that people ask? the Reason being, it has a failsafe built into the ecu to pull timing when it reaches a certain temp to prevent detonation and breaking off the first ring land.


The 'failsafe' Sprintex uses isn't unique to the SMT6, plenty of other piggybacks have that capability (a map switch triggered by a post-blower temp sensor). However it seems alot of tuners lacks the patience/awareness to implement this feature into a tune with a new piggyback, and just tune a single set of maps, with no failsafe. For this reason I recomend Sprintex owners stick with their sprintex-tuned SMT6, unless they wish to change to another puggyback and are confident their tuner knows what they are doing with it, and will set it up like the Sprintex SMT6.

The 'failsafe' Sprintex uses isn't unique to the SMT6, plenty of other piggybacks have that capability (a map switch triggered by a post-blower temp sensor)...........I recomend Sprintex owners stick with their sprintex-tuned SMT6, unless they wish to change to another puggyback and are confident their tuner knows what they are doing with it, and will set it up like the Sprintex SMT6.
Exactly, my tuner will be running a safe second map in my Unichip Q to pull the timing when the blower temp sensor gets too high. It's not rocket science you just need a tuner to be competant & take the time which I'm sure they would if you requested that feature.

The Sprintex kit was a good stepping stone as it got the ball rolling for Magna FI, despite several turbo installs prior there have been very few if any turbo installs since the Sprintex kit rollout and Raptor SC availability.


True, but only because everyone here is too lazy/scared to do a F.I upgrade that doesn't come as a kit :cool: .

Basically - EZ boy has answered the question perfectly. It's all to do with the timing that needs to be adjusted to account for boost, not just the fuel. The the OP - you will not get an answer that is "facts from members who have tried this", because no one has been stupid enough to do a FI install on a fuel injected magna without some form of tuning of the fuel / timing.

If you're talking 4psi max, and running 98ron fuel, then maybe you won't destroy your pistons in the first 6 months, but I ask you - is it really worth the risk?

I don't see why hitting a mapping ceiling would be an issue, seeing as how there are examples of magnas around putting out good numbers with either a remapped factory ECU (jasonsVRX), or factory ECU + piggyback (RPW TT magna). Never heard of anyone hitting a mapping ceiling on a magna ECU. Once again, if you know something I don't, please share :)



Thats just what i was thinking:thumbsup: factory ECU is the one responsible for fueling anyway if a piggyback is used.



Stock ecu: poor/scary fueling, but mostly timing is way off. LOTS of timing needs to come out at boost. DO NOT DO IT. The same reason a NA Lancer doesn't become an EVO by adding a turbo and nothing else.



talking about timming, how much will it have to be retarded?. i am assuming you wouldnt advance it further as this would lead to detonation.

Now if a positive displacement supercharger is used(not the centrifugal type like raptor), boost should theoretically be constant throughout the rev range. Does that mean that a constant retardation of the timming further in relation to the stock ECU timming will work?

For all using any sort of piggyback computer with a positive displacement supercharger like sprintex, if it is known, approximately how many degrees does the piggyback alter the CAS.

Also if anyone has backed up fuel and timming maps of their setups, it would be interesting to know.

Is this a question of wether or not it can be done just for some conversation, or is this a question of the cheapest way to do this?

Personally - how much is your engine worth?

I know the supercharger kits come with piggy backs/ecu's. Apart from that Haltech can make a plug and play ECU aswell, depending on where you are tuning isnt that bad either.

If you're talking 4psi max, and running 98ron fuel, then maybe you won't destroy your pistons in the first 6 months, but I ask you - is it really worth the risk?

Definately not worth the risk. but how can you be sure? Even with a piggyback, there have been problems. I suppose you need a knock sensor installed, or some way to monitor pinging. A second fuel map would be helpfull, especially if someone went and put bad low octane fuel, the knock sensor should be able to detect that and fuel map changed.

Is this a question of wether or not it can be done just for some conversation, or is this a question of the cheapest way to do this?

Personally - how much is your engine worth?

I know the supercharger kits come with piggy backs/ecu's. Apart from that Haltech can make a plug and play ECU aswell, depending on where you are tuning isnt that bad either.

This question is put up for other questions to be asked. :D no actually just general knowledge and possibly a future conversion.

Well the engine would probably cost less than a supercharger. I mean I have seen them(6g74) go for $500. so the cost of getting another engine is not the problem, the problem is the work involved fitting it. Anyway i don't want to damage my engine(its well taken care off). Going FI on a NA car is risky for anyone, reliability is always going to be an issue if tunning is not monitored properly no matter which piggy back you use.

This question is put up for other questions to be asked. :D no actually just general knowledge and possibly a future conversion.

Well the engine would probably cost less than a supercharger. I mean I have seen them(6g74) go for $500. so the cost of getting another engine is not the problem, the problem is the work involved fitting it. Anyway i don't want to damage my engine(its well taken care off). Going FI on a NA car is risky for anyone, reliability is always going to be an issue if tunning is not monitored properly no matter which piggy back you use.

Provided its setup correctly you wont have too many issues.

Definately not worth the risk. but how can you be sure? Even with a piggyback, there have been problems. I suppose you need a knock sensor installed, or some way to monitor pinging. A second fuel map would be helpfull, especially if someone went and put bad low octane fuel, the knock sensor should be able to detect that and fuel map changed.

I can't comment on the problems with FI cars and Piggyback ECU's. All I can comment on is that there have been no issues with my tune. A second fuel map, and knock sensor would be helpful, so would a fully tunable electronic boost controller to bleed off boost if things go wrong - it comes down to how much you want to spend on the day and the cost vs benefit.

A second tune - you're looking at probably another half day on the dyno, a knock sensor - well you'll need a piggyback ECU to talk to that, so there goes your "non piggyback supercharger setup" anyway, and a good e-boost controller which is fully intergrated with the ECU - well you might as well buy a real performance car if you're going to spend that much on top of a boost kit for your magna.

i also put it to you that finding an aftermaket knock sensor or universal item to install onto an engine that doesnt have one standard would be harder then putting all these ideas into practice. A knock sensor works on an engine long before you can hear the knock yourself, as knock sensors are designed and set at the factory to hear the onset of a knock event through the resonance of the block, which would be and is, different for ever engine ever made. You would have tos epnd as much money on the dyno to work out where its kncoking and where its not to set one up that you could just tune it richer and not have a worry. Im sure you could set a knock sensor up to trigger a 2nd fuel and igntion map but chances are for it not to get bad signals and noises causing this to happen irratically you would probably do a ringland or headgasket first.