I'm modifying an S4 NA w/ a Millenia supercharger and will be using an aftermarket/junkyard throttle body. One of the choices was one off a 300zx which comes w/ a full range tps. The other choice would be one off a Mustang also w/ a full range tps. The stock TB on the engine will have throttle plates removed and the throttle cable run to the new TB. An SAFC2 will be added for enrichment control as well as larger 550/680 injectors.

The question is whether I should retain the stock tps or try to connect the new tps. I'm not sure if the stock ecu would work with these tps units but in my research I've found that they're also the 0-5v range type however they'd read over the full sweep of the throttle range. Will it mess up the ecu's "tune" using the full range tps?

 

im thinkin you cant do that. but im not 110% sure .? someone chime in....

 

I know I've read in some other searches about someone trying to convert to an S5 TB for the use of the full range TPS but none have ever mentioned the ecu or answer the question of whether it would work on the stock ecu.

 

Anyone?

 

if your using some form of piggyback controller like an emanage im pretty sure you can make it work.

 

No, Trying to keep the stock ecu. Just want to know if the ecu would get "confused" having a full range tps attached.

 

eh...boosting a stock motor with stock ecu. not going to end well.

 

Sorry man, But I beg to differ. And with an SAFC2, larger injectors and FD fuel pump it should feed more than enough fuel to boost to 8-10 lbs. which should be my upper limit anyway. Not trying for some extreme amount of HP, Just trying to gain some usable low-midrange oomph without having to go too far modding the NA. Was hoping somebody might have done something similar w/out going to a standalone ecu but it doesn't seem so. I guess it will have to use a boost sensor for the SAFC throttle % for reference rather than TPS. Still wonder though which would be more accurate for the SAFC. Oh well.

 

+1

how are you going to control timing?

 

Your going to want a standalone.
I'm pretty sure you will have to speed up your timings to make your setup efficient.
I'm no tuner though/

 

Stock timing should be OK up to 8-10 lbs. boost. AFR much more of a concern than timing otherwise an MSD w/ boost/timing retard function is what I'm sort of thinking about however if it comes down to it, I would go Megasquirt that Zeal Engineering is offering. W/ the supercharger it would be a lot more predictable when the boost comes on and boost creep would be a non-issue also. If so many NA_turbo conversions have made it w/ the stock ecu why not a blower? I know there are those who've made the conversions w/ a T2 ecu also but I dont think I'll be going that route just yet.

 

10 lbs on N/A timing will be pushing it

 

Like I said before 8-10lbs. will be the upper limit. Intercooled and w/ the right air/fuel management I think it should still be safe. The pulley ratios have been calculated to achieve about 8 lbs. at 8K rpm's the10 lb. upper limit is just a safety buffer. Anyway, We're getting away from the original purpose of this thread which is to find out what the stock S4 ecu would do with a full range TPS. And I still wish that one of the gurus would chime in. It's just been a nagging question about how the ecu would behave w/ one.