RE-EGI TPS compatibility with later years?
 

I've recently acquired a 6 port RE-EGI 13b from an '85 GSLSE. Buuuuut it's missing the throttle positioning sensor and the entire intake section before the throttle.

Does anyone know if a TPS from a later gen rx7 or a totally different car works as a substitute, or even if the intake section fits the 1st gen 13b? It'd make it a lot easier to find a replacement if I can look for more than just a GSLSE parts car.

A new TPS is 300 bucks on rockauto so I thought id ask!

Roland

First off - the TPS on the GSL-SE is a linear potentiometer mounted to a metal flange that bolts to the Throttle Body. This arrangement makes them pretty unique to the -SE intake system. That said, you may be able to retrofit a later generation TPS to a bent piece of metal, as there's nothing magic about how it's mounted - just that precise dimensions of the linear potentiometer so you get the right readings at idle and WOT that your ECU is looking for.

When you say you're missing 'the entire intake section before the throttle', (body?) that means you're only missing the rubber air intake tube, and the Air Flow Meter and airbox that it attaches to. If that's the case, you could probably fab something up - but it depends on what you're installing this engine into. Can you elaborate in which model or car you're mounting this engine?

As to the intake system, you'd want to run it past the 2nd Gen forum guys, but all of the 2nd Gen cars (except the T2) have 13b, 6-port engines and the intake should match up to your -SE engine. There are internal engine differences (water jacket seal location, rotor weights, Apex seal dimensions, etc.), but the bolt patterns for the 13b intakes should be consistent across the models, which should make fitment easier. There were guys retrofitting the 2nd Gen intake to the -SE engines, so I know it works that direction so it should work the other direction, as well. That might fix your problem with the TPS, too.

Good luck, and post back,

Hey Longduck,

Thanks for the detailed reply! You're right about the section I'm missing - air intake tube, airflow meter, and airbox. I'm hoping to drop it into my 1980 SA222C, just for street use with the odd casual track day.

Sounds like bits from an FC could work then, which is encouraging if I can't find another GSLSE. The potentiometer talk/making sure it's calibrated correctly is over my head though!

Roland

The electronic portion of the S4 NA TPS is the same. If you can't find the S3 parts for a reasonable price, It may be cost effective to find an entire S4 intake and perform the retrofit (easy) as it will come with everything you need, including the TPS. (LIM, UIM, dynamic chamber, throttle body, and boots.

thanks man! Those should be easier to find. Good to know I have options!

Roland

I've done the full S4 intake swap. Yes it bolts up other than little bits here and there needing to be modified. The acv port on the center iron has to be blocked off. I used angle aluminum bolted onto the LIM. The oil injector threads are aimed differently so my early oil injectors had to have the vacuum ports bent. The center iron intake ports are also smaller on the SE than the NA S4 so it'll have a step in. As stated, the S4 NA tps works no problems on the SE ecu.

Any kind of performance benefits to the S4 intake onto an S3 (SE) engine core? Just curious, and the OP may be headed in that direction anyway. TIA,

I don't think it's worth the time and effort swapoing from an S3 to an S4 intake. When I did the swap I went with the S5 and with Haltech to make it worth my time. I figured if I were going to mod the intake I may as well reap the benefits of the VDI. Works well so far.

I beg to differ. I noticed a difference on my 80.

Well, not doubting that you didn't notice a difference. But if you think about it, with the 2nd gen (S4) they went to four fuel injectors, a bigger TB and intake, lighter rotors, way better ignition coils, (Direct Fire), etc. And with all of that it only yielded 11 more horsepower than a GSL-SE. Without a stand-alone ECU, you will never reap the full potential of that intake. All things left stock, you will simply have "about" 11 more hp IMO.

i checked today, the N236-18-911 sensor is available, and Mazda has quite a lot of them, not cheap, but you can get them