Car is BP running a Link pnp, and for reasons firstly cruise control, secondly gadget freak, and thirdly don't have enough unfinished projects, thinking of going down this path.

Spoke to the Link stand at WTAC last weekend, they referred me to one of the teams who are a Link dealer/tuner who claimed to have done a few. Bloke seemed to know what he was talking about, rattled off a range of TBs and pedals that worked, but it was a short convo, he was in the middle of debugging one of the cars.

So the question is - who has done it, what ECU, and what are the 'gotchas'. Also what TB and pedal to use.

Bonus points for what this has allowed you to do that wasn't possible before.

Happy for the K24 people to chime in too.

The clock starts NOW!

 

Done it on my K24 swap.

• Haltech Elite 1500
• Bosch 74mm throttle body from a Porsche (Bosch 0280750474)
• Subaru pedal, I think? I'd have to check my thread again. Not a huge fan, but it's good enough.

Only gotchas I've hit so far is that the Bosch doesn't like vibration and the K24 creates plenty of that. I bought the Winning Formula DBW Anti-Vibration Kit to mount the throttle body once the engine goes back in the car. I hope for no further issues.

I'm not using its full potential yet, but what it did do right out of the box was relieve me of having to think about idle. I have no idle valve, no extra plumbing for an idle intake. I just tell the Haltech where I want the idle to be and it deals with it. Full disclosure, my car doesn't see use in cold weather and I don't have anything like A/C creating random idle loads, so it's not like idle was going to be complicated. I don't know if this counts as KISS or not, but I feel like I can say it is. The Haltech supported the Bosch right out of the box, I don't think I even needed to tell it who made the TB, I think I just told it how the pins were connected. It calibrated itself after that.

One day I hope to have excess power that I need to de-tune out via DBW. We'll see how soon that day arrives, if ever.

Bosch throttle bodies are used on a lot of Euro cars, including some pretty plebeian models, so availability should be pretty good as long as the bolt pattern doesn't interfere.

It takes a little fiddling to get the pedal height and placement right, that's about all I can think to complain about.

 

You can use any pedal that you can easily get in your region (including the connector/pins) that someone's mounted in a Miata. That includes any DBW K swap, LS, Ecotec, LFX, J-series, etc. A lot of U.S. builds will use GM pedals, but I've heard a lot of Euro builds using Honda Fit or NC pedals. BMW makes great floor mount options if you wanna try something new. They'll all have 6 wires. 2 grounds, 2 5-volts, and 2 signals.

Then find a Bosch throttle body in the 60-70mm range or similar. Again these will have the same 6 wires, plus 2 additional for power and ground. The grounds and 5v could be combined on either of these to bring the plugs to 4 (pedal) or 6 (throttle body).

These guy's use NC components and have everything ready for a BP swap. I especially appreciate the zinc coated throttle pedal bracket:

https://www.g19engineering.com/index.php?cat=88

 

Engine:

• BP4W
• Junk2 Inmani
• MaxECU Race

Pedal:

• K-miata APS adapter bracket
• Honda Fit/Insight APS

DBW:

• my kuztom DBW adapter: https://www.thingiverse.com/thing:6478036
• Honda K20C* 60mm DBW

Benefits:

• APS vs DBW calibratable vs rpm/mph/rain map/etc.
• cruise control
• direct idle speed control
• 2 pedal driving w/ auto blipping downshifts
• tork management per gear/veh speed/etc.
• full authority traction control

Everything modern should have 2 APS and 2 TPS sensors. The only caveat is that some of the newer kraut junk may use CAN I/O.

 

On my turbo NB2, with NC throttle body and adapter from Bill@MiataRoadster. Running on Extreme MS3.

 

Thanks guys!

The mating of the TB to the (flattop) IM is a problem, due to the bolt pattern. I was expecting to have to do something to interface with what seems like circular bolt patterns, though maybe somewhere there is an OEM that is non-symmetrical out there somewhere. I think I will start searching the OEM replacement parts suppliers for TBs, but unless I can find a direct match (or near as) I am going to have to make or buy an adapter of some sort. Alternatively, take to the IM with a bandsaw and weld on a new plate with the requisite mounting configuration.

Curly, they want 42 GB pounds for that TB adapter, and another 51 to post it to here - ~$200AUD. I think I can get one made here for less, perhaps without the O ring though.

Reverant, I can find nothing on Bill's site, I have emailed him.

TBB, that's a good point about cold start - we have minimums around -5 to -9c, and the Sydney bloke won't know anything about that.

The G19 pedal bracket is looking good though, expensive but the easy button - if I can find people who use and like them. I don't want to be a beta tester or pioneer.

E2W, will look into the Kpower bracket. We don't have the Fit, but that is probably sold here under another name - hopefully, as that donates a few things including the TB!. What is 'APS'?

I have an embarrassment of riches here, plenty for me to followup on. I think my first priority is to see what the hell a Honda Fit is, and whether we have them here. If so, that sharpens my focus. ETA: Honda Fit = Honda Jazz, quite popular car here!!

Thanks again all! Cats all round - this site rocks!!

 

I spent quite a bit of time looking at DBW throttles. I settled on the Honduh stuff, mainly because I used to work at R&D and had access to all the spec docs and drawings. It's also cheap, plentiful, reliable, and fit my requirements. If you don't want 60mm, then there's smaller on the L15 and bigger on the K(N/A) or J series
The issue with the NB is that the bolt pattern is asymmetric due to the IAC, and there's no reason for any standard DBW to be asymmetric. Also the bolt pattern is just close enough to **** you off. Meaning nothing lines up and it's just close enough you can't simple make a plate with 2 sets of holes. So then you need to cut the flange off the inmani or make an adapter and clock the DBW. Which I chose the latter.

 

I know this is going to be well outside of your price range, but the Winning Formula kit is a brilliant solution mating incompatible throttle body bolt patterns.

https://www.winningformula.shop/prod...dy-adapter-kit



I 110% encourage buying parts from the people who develop them, but given that WF doesn't have a BP manifold adapter and the kit is designed for a much bigger throttle body than you're going to use, I'm ok with suggesting you make your own one-off.

APS = Accelerator Position Sensor, I think.

 

Don't look for a bolt on solution when it's too easy to weld one on. I'm fortunate enough to work with a highly skilled welder that could probably pump out a half dozen modified manifolds an hour, so it's easy for me to say. But he's not the only good welder out there, find one, buy a weld on flange for whatever throttle body you decide on and don't look back.

 

Thanks Rev, Bill says 'Hi', and you got a prototype that never went into production. He checking if there is a second lying around.

Yes, agree Curly, that is where my thinking is taking me.. I have started looking, the Jazz mani is plastic, the ones I have seen. Next step, NC? Not worried though, as you say - some scrap aluminium plate, a bench drill, and someone to weld it on: job done.

Not real happy about taking a bandsaw to a flattop, but if that is what it takes I'll do it in a heartbeat.

 

Flattops are $~250 now, easier pill to swallow than when they were $400!