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Hi members, have read the post about Chiptorque and have contacted them.
I have looked at their dyno sheet and estimated gains.
My question is My SP has a GFB EBCii fitted and I have scramble mode set to 9.7psi.
I use this mode when I want a 30 second squirt if power for overtaking ect.
For $800 is it worth updating my stock tune to the new Chiptorque one and then this will effect my EBC and make it obsolete unless they keep that tune maximum boost 7psi
Plus will the SP handle their new chip and power.
I don't want to go the whole hog ecu change have been quoted about $3000 and to me that's not the best bang for buck.
Your thoughts and experience will help me out.

I'd be more concerned regards bent rods. SPs tend to have a tendency to do it on stock boost. Even a few extra psi is dicey.

Cheers what causes these bent rods. Like if I turboed a stock NB with the same rods would they bend too. Did the SE come out with different rods or just lower boost.

SP IS an NB8B. NB rods are weak. So yes, you will have the same problem with any NB that has not been rebuilt with a forged bottom end. Potentially - there are lots of SE/SP/NB8Bs that have been turboed without a built bottom end - Dann would be best to speak to about those though, and how to avoid problems with the rods.

SE has the same problem. I was looking at a stripped SE yesterday, one hole was a mess - rod in about five pieces, a big groove worn into the big end journal, piston with detonation all over it. Luckily, the block looked ok, amazing! That one was not just a rod failure, looked like there was a bit more to it.

I have a spare BP which I will be starting on soon for a forged build for my SE.

Ok cheers. what a shame these cars have that issue. I will drive it till something happens then and part it out.

They don't tuned right.

This is why the expensive electronics are so popular.

Thanks Dan. I spoke with the people at Chiptorque and the guy told me the person that has the upgraded chip is the one who initially developed the chip for the SP. it even says it on their website. I will contact them again and see if the new upgrade chip is tuned right to avoid bent rods.

Thats absolutely true, i would argue that its a good example of how unsuitable this method is, if its hardly gold enough for a stock one its unlikely to be better for a modified one.

SPs have always had some gremlins, but I know people with chiptorque reflashed SP (the product you are considering) and they were satisfied with it for a while.

The issue is that the NB ecu is hardly suitable for an SE, let alone an SP, even further again let alone an SP with mods. Just be informed and you might find its the right product for you.

Dann

Dann I really appreciate you help and advice. My SP isn't modified except for a straight through exhaust and a GFB EBC. I generally find I change gears around 5,500 revs as that where I feel the torque is best. I hope I don't ever get any issues with it and just want to look after this car as best I can. Yes a new ECU would be great but at this stage have spent enough money on this car. I will keep you all updated with any findings from Chiptorque I will call them on Monday.

Thanks Dann, I get to make another pun.

roshmx5 wrote:I will drive it till something happens then and part it out.

OP, have you heard the saying 'penny wise, pound foolish'? You can spend money incrementally, and find yourself in a corner where you need to spend a lot more. Or you can do it right, first time. And enjoy the car without worries about breaking it, and in the confidence that when it comes time to part with it, you will get good money for it.

Compared to a running, well tuned SP, a part-out of an SP with a broken engine will net you small change. At worst, the engine, head and turbo will be unsaleable junk, leaving you with an engine-less, turbo-less NB8B - IDK but say $3-4k? Maybe the SP airbox/vin would push that up a bit if it was sold as-is. If you are really lucky the turbo and head are useable, so maybe add $1-2k? As you may have seen, I am parting out three MX5s, and I can assure you that I am not getting rich!

Of course, you may have a troublefree run with the car, and we all hope that that is the case, but unfortunately, for all the reasons canvassed here, that is not always so.

Your car, your money, your choice.

:mrgreen

I agree mate and will take it easy in the SP. there just is a lot of information talking about bent rods ect how it happens and the cause of it. The car is 16 years old now and I suppose if anything was going to happen it would by now. In saying that not sure how other owners drove it. Was just wanting to know why the rods bend. Is it the tune or is it weak rods. I am getting my head around it all.

They bend because they are made of bendable material. How much force it takes to bend them is fixed and is the same on all models of MX5 (and mazda 121, 323, ford laser etc, they have the same rods).

Whether or not your setup puts that much force on them or not is what changes whether they bend or not. the stock MX5 ecu is utterly incapable of doing a good job running a turbo engine. The ecu has NO IDEA that boost pressure even exists, it was never meant to run a turbo engine. The SE ecu is a mazda/denso workaround. The SP ecu is a "guy in a shed from brisbane" workaround. Regardless, using the stock ecu for any boosted application is dicey because its constantly being tricked to output a 'close enough' set of signals to run the engine. Stock SP's are known for bending rods because the ecu has such poor control of the engine. Adding more flow and more boost and of course, more timing is only edging you closer to the same fate if you;re expecting the stock ecu to do the job.

Aftermarket ECU's run different sensors and calculate requirements differently, with boost pressure in mind. As a result they more accurately control the car allowing you to skirt the fine line of engine damage but with a guarantee that you never ever cross it.

Dann

roshmx5 wrote:suppose if anything was going to happen it would by now.

As Dann is saying, anything can still happen to it - it all depends on what you do to it in the future, or have done to it in the future, assuming it's all good at the moment.

With age and kays it is more likely to happen now/later.

Cheers again guys. What is the best cost alternative to the stock ecu