TII build up with S4 NA rotors...
 

Alright, from my searching.. this topic has been covered a few times in a few different ways, however I was never able to find any exact answers to what I'm looking for.

Mainly, I'm worried about fuel, I can take care of everything else. Fuel is of course where these setups are always guaranteed to go wrong.

I'm looking for an opinion and I'm doing my best not to assume anything.

I "thought" about going rtek 1.7 with XXX primaries and XXX or X,XXX secondaries with an SAFC to tune. Any opinions/help would be greatly appreciated. As of now, I don't have anything other than a stock TII ECU. So I'd like to get my affairs in order, then purchase the items needed to tune this particular setup.

ok i'm lost... you already have a TII that the engine was rebuilt with s4 n/a rotors? or you plan to do this later?

i used the s4 n/a rotors in my TII and it's great.

regardless of what your doing.. the safc/ rtek won't get you very far. if your going to run stock turbo and barely up the boost then you'll be fine with that.

I'm building this setup. Currently collecting the rest of the parts I need.

Basically, I got sick of screwing with the porting of the manifolds and all that crap. I ended up with ALOT of vacuum leaks. I initially tried just putting a turbo on my NA motor with an SAFC and didn't change out any of the NA electronics.

I'll now be using a s4 TII ECU or Rtek 1.7 with TII coils and etc.

So yes, the motor is being built. I don't plan (at this time) to go beyond the stock turbo at 10-12 psi max. Even that's higher than I want to run, but let's assume over a 1-2 year time I'll get ambitious.

So, this setup only needs to get me through a year or two on the stock turbo. In the spirit of repetition, I'm trying to figure out what primary/secondary injectors are going to keep me safe, and wether or not the Rtek 1.7 combined with an SAFC is going to be enough to control the fuel to this setup.

Thanks

gotcha... my main concern would be that the rtek can't control anything but 550's and 720 secondaries right? i'm not positive on that but if that's true then that sux because to be on the safe side i would run atleast 720's all around. or the typical 550/ 1600 and your set from here on out.

or you could try 550/ 850 and hope the safc will help you lean that junk out if need be. on the stock turbo regardless of compression and port job your not going to make but low - mid 200's at most. so 550/720 may clear you.

The map on the Rtek is set for 550/720 based on the assumption that you're running a standard TII motor with more boost than normal, or at least that's what I've gathered.

My worry is that the map won't be good enough on NA rotors on the low side using 550's as my primaries.

FWIW, I had a REALLY hard time controlling 1000cc injectors with just an SAFC and NA computer. As far as I could tell, at around 5500 RPM, the car was just flooding to hell and back, I couldn't get any spark, etc etc. The car fell flat on its face at 5500.

I have streetported TII w/ S4 n/a rotors and run an Rtek and AFC-2. I think your idea will work great for you. The compression difference really didn't seem to make much of a difference in my A/F ratios. I my AFC settings were pretty much the same before and after swapping the higher comp rotors in, I say just go with 550/720 combo and rtek 1.7. Mine even ran decent with the AFC zeroed out. most of the tune on my AFC is for fuel effeciency.

Thank you very much. Exactly the kind of information I was looking for!

I've ordered everything I need to do my build except new side seals for the rotors (mine were not reuseable) and I'm getting very anxious to get her rebuilt and start it up.

Thanks again!

sounds like you are talking about the samething i am going through myself. can you answer me this questions. If i am running a stock turbo on an 88 rx7 i can use n/a rotors with no problem?