noch

So I have my s4 TII now and I am tearing it down for a rebuild. Is it a good idea to street port it while I am attempting my first rebuild or is that going to just complicate things more? If I port it should I go ahead and upgrade the fuel system and get an Rtek7? The car is bone stock with 137K on it and is strictly for fun. My plan is to rebuild it and get it running good, then start bolting on some HP. I don't plan on exceeding the limitations of an Rtek7 2.1 and an upgraded fuel system so nothing crazy.

I am having a blast tearing down the engine. Much more fun when your toy is not your daily driver

RotaryRocket88

iTrader: (7)

It would depend on what your goals are and what size of streetport you intend to do. Personally, I prefer stock ports or a minor port job in forced induction applications because it preserves low RPM torque. If you need more power, you can always just go with a bigger turbo. If you port the engine, leave the stock turbo in place, and run it at stock boost levels, you will be just fine with the stock ECU and fuel. The stock turbo is on the small side, and it will limit any gains you would see from the porting (and also keep airflow within stock fuel limits). If you intend to run higher boost or use an upgraded turbo, you will need supporting fuel and fuel control modifications.

dwb87

iTrader: (22)

I think I know a decent set-up for you.

- RTek 1.8
- 720cc primary fuel injectors
- 850cc secondary fuel injectors
- A hybrid turbo with ported wastegate + S5 divided manifold
- Turbo heat shield
- Racing Beat REV TII exhaust (Or something else free flowing or more affordable.)
- K&N drop-in filter for the stock airbox or K&N cone filter with custom filter box + custom ducting. (Keep that hot air away from your filter.)
- *Sandwich mount intercooler set-up
- Aluminum radiator and silicone coolant hoses
- Aftermarket boost gauge, water temp. gauge, oil press. gauge, and oil temp. gauge
- FD fuel pump or Supra TT fuel pump or Walbro 255 LPH fuel pump
- Complete fuel pump rewire


BNR Supercars build high quality hybrid turbos. -> BNR Supercars

If you're looking for a cheaper DIY route, check out RotaryRocket88's turbo rebuild and hybrid build link -> https://www.rx7club.com/2nd-generati...hybrid-959045/

noch

Thank you both for the input!

Well the engine is just about out of the car. My rebuild video should be here today and I have watched Aaron Cake's twice.

I have a lot of work to do on the car so I have decided to just do a mild (the smaller pineapple or RB template) street port as I rebuild and get everything running good in a stock condition. dwb87, thanks for the detailed layout! I like that idea. I defiantly am considering doing a BNR upgrade/rebuild in the near future. Figure if I keep it simple the first time I will have little less of a learning curve to build on and less to troubleshoot.

Thanks again. I better start doing some work and stop reading so I can pay for some of this

noch

Ok, so I have started ordering parts but before I start getting into the more expensive areas I wanted to clarify something if possible. I have been reading and reading away on the forum. Here is what I have planned out:

Fresh engine rebuilt by Rotary Resurrection
RB full exhaust
Rtek 2.1
Walpro in tank fuel pump
750cc injectors
BNR stage 1 or 2
FMIC
Aluminum Radiator
All new hoses and fluids, etc

I originally planned to do all this in a phased approach but then it seems that if you start doing anything you need to port your wastegate. If you are going to do that you might as well get a stage 1 BNR while you are at it. If you do that you need more fuel and so on. So rather than tearing stuff down constantly its seems to be better to just build it all at once.

So my question is when I get all of this hooked back up and fire up the engine is it safe? I will get it tuned but can you drive it around without blowing it up (i realize that's a loaded question). It seems a wideband and some other decent engine vital gauges will help keep it ok but I was just wondering if the Rtek set to the right injector setting along with a conservative break in driving foot should be ok or if if it doesn't work like that.

RotaryRocket88

iTrader: (7)

You can drive the car around if you stay out of boost. 4x750cc on the 720/720 setting is basically stock fuel. That's how the presets work. Injector d/c is adjusted so it runs as stock, but you have much more headroom before the injector maxes out. 4x750cc is also about the bare minimum for a hybrid of BNR stg. 1 size or larger. I would suggest secondaries that are a littler larger. In my case, 880cc injectors.

Before doing any sort of spirited driving, you'll need to revise the timing map (see Rtek section, timing map thread made by Arghx), add fuel in higher boost cells, then datalog with a wideband. Fuel can be removed to adjust things into range. You always start rich, then trim back to hit a target AFR.

I'd also suggest a Denso pump (FD, Cosmo 13b, Cosmo 20b, Supra) over a walbro. Walbros have a checkered history, are noisy as hell, and overrun stock FPRs. They're popular because they're cheap and flow a lot.