Question about ecu tunes (JWT, Enthalpy, etc...)

[AZ89two4Tsx]

Ok probably a N00B quesiton but here it goes.

Since the ecu is retuned and set for a specific boost level, does that mean you can't adjust the boost with a boost controller? Will it run like crap and risk damage? Is that why people tend to go with a SAFC or an Emanage instead of a ROM tune? Idk, just wanted to know as I might be going KA-T instead of SR. But again, I've heard you can turn up the boost no problem on a stock SR up to 12-13psi (max turbo efficiency), so would the same apply to a ROM tuned KA-T?

[Chris28]

It's not tuned for a specific boost level, it's tuned for a certain size injector and a certain maf. Timing is also changed a little bit. With increasing boost, it's up to what your maf and injectors can handle. If the tune is for 550cc injectors and a z32 maf, then the tune is going to be able all the boost it can until either the maf or injectors is maxed out, and at that point it's nothing with the tune, it's just the maf and injectors can't handle it. I think that's right, but hopefully an experienced tuner will come in to fill the gaps haha.

edit: SAFC and Emanage should not be used to tune the car, they should be used in conjunction with a rom tune. They are for slightly adjusting afr's so you can lean it out when cruising or w/e, but are not made to be the only thing used to tune your car.

P.S. I'll be running an EFI Specialists tune. On their site they have like 3 tunes, and they are classified by maf and injectors. On the one I'm getting, mild boost, they say it's suitable for the stock ka maf, 370cc injectors, and a small turbo such as a t25. That means any range of smaller turbos, some being capable of higher boost than others.

[DevilMB3017]

Just adding a bit...

With a ROM tune, they build in the fuel maps for your injector size and MAF, along with variables you may have like different compression pistons, cams, etc. depending on what tuner you go through.

Then, as I'm sure you've read in different stickies and such here, you need to retarded timing typically per every couple of pounds of boost over 7-8 lbs. The ROM tunes will build that safeguard into their ignition tables.

Since there is no stock sensors for boost, the ROM tune ECU doesn't know how much boost you are running, it only knows the amount of air going in through the MAF and what the O2 sensor is reading after ignition.

Some people use just an SAFC or Emange piggyback because it's cheaper. This can be succesful, but it can quickly damage your motor too.

[AZ89two4Tsx]

It's a high probability that I'm going KA-T and it's obvious that the tune makes or breaks the kit along with a quality turbo. I was thinking about either getting a ROM tune or having a local shop dyno tune it there. It sounds like a dyno tune is best because it's specific to your vehicle and not just a "universal" type thing. Either way, would I still want a piggyback to fine tune the afr even more? I would have absolutely no clue how to use one and I hear instructions are complicated.

Btw, my setup is going to be realtively simple. 370cc injectors, fmic, etc. I can't decide on whether to go with a t2 or a t3/t4 turbo. I'm trying to make around 200-250HP getting the best mpgs as possible so I was thinkin a t3/t4 because it spools are little slower. Idk, it pretty much all depends on budget and parts availability.

[DevilMB3017]

Dyno-tuning locally is almost always your best option since they'll see the actual affects of different maps. You may want a piggyback on top of that to lean it out a bit when your not 'getting on it' or something.

I'd suggest locally tuning or Enthalpy/JWT/someone without neg. feedback.

[oz240red]

hey guys, so is it possible to get a ROM tune on a local dyno? I'm also new to KA-T and though that the only way to get ROM tunes was either JWT, Enthalpy or E-mance ??

[DevilMB3017]

Technically, anyone can do a ROM Tune.

All a ROM tune is is this: Someone takes your stock ECU, and removes the memory where your fuel and ignition tables are stored. A chip is placed there that is able to be read/written to.

You'd have to contact your local tuner - some will be willing to and others won't.

I know it might be a little far from Miami, but Enthalpy is down there in the area, kind of. You might want to contact him if your interested in dyno-tuning.

[oz240red]

will do!

though I'm going to research whether there is a tuner in Miami, because it would be easier to tow the car there.

When I was shopping around for a turbo, I asked the owner of Speed Shop, in Miami if he could ROM tune, but he said I had to get him the software. I think someone here in the forum put a link for this software...

[DevilMB3017]

Depending on what your final goals are for your car, you might want to look into a standalone engine management such as AEM EMS. It's a plug and play direct into your stock ECU harness.