Hi all! I've been wrapping my head for the last week trying to figure out what I need to get for my initial modding. The goal is to get as much HP without moving to a bigger turbo. I don't know if this is realistic or not, but i'm aiming for 280 rwhp. I've found similar threads, but they all seem to be for people planning on swaps, or people that just have their N/As.

Here's where things stand;
- The car is a 87 TII with 120,000 kms, very well taken for, pretty much a sunday driver. it will be taken to Mazdee's outside of toronto for a maintenance tune-up.
- The car is stock, EXCEPT for a full 3" Racing Beat TII exhaust system (Downpipe, Straightpipe, Dual catback exhaust) and a short shifter.

now, from what i've already read, here's what I need:
- Port the wastegate - I was wondering better, porting it or just getting a bigger aftermarket wastegate.
- RTEK chip - I was looking at the 1.7, but getting the 2.1 would eliminate the need for a sepaerate fuel/boost controller controller.
- 720cc injectors - Gotta get 2 of these for the secondary injectors so as to not run lean
- Walbro 255 - I heard an FD pump would work as well, which would be best?
lastly - Intake - I'm figuring the stock intake box would be too restrictive for higher boost, need ideas on what to get.

Basically right now i'm hitting fuel cut because of the RB exhaust. I want to raise the boost, but i've seen so many numbers thrown around on the forums, i'm just confused as to what i can reach with the stock turbo without running the danger of it just blowing up. I also need to know if i can install these parts one at a time, or if i should just wait until i've gotten all of these parts and install everything in one big go.

I need help guys, please grace me with the internets boundless knowledge :P

Cheers!
-Alex

 

You might hit 280 RWHP on a spectacular tune. More realistic is 260 RWHP.

Your plan sounds solid. The FD fuel pump is basically the TII fuel pump with about 20% more flow, and should be good for this application.

As for the airbox, you are on your own there. No good kits exist so you will need to fabricate up a TID, install a cone filter, and then make your own airbox.

 

alright, at least i know what i want to do makes sense
Now it's just about getting the specifics sorted out. How high can i boost? where can i find info on designing this intake, i know i've seen many people with aftermarket intake done up, heatshield, etc. then there's still the wastegate issue, buy a bigger aftermarket wastegate or get the stock one ported, which is the better solution, how easy is it to port, what kind of time does it take to do this. i've read up a bit on the DIY porting, but it still seems like a whole lot of work compared to just getting an aftermarket one.

Thanks for the help!

 

The general opinion I have gotten from reading on here is that 10 psi is the most you want to run on stock injectors with an upgraded pump. With 720cc secondaries, you can increase the boost to 12 psi but you are then at the stock turbo's top end of its efficiency plateau. Higher boost will significantly shorten turbo life with no gains in power. How close you want to push your car to that edge is up to you.

As for wastegate porting, I dedicated a little over a weekend with a buddy. I had to wait until Monday to take it into work to get the extra washer welded in, otherwise it coulda been back on the road sunday. I did end up shearing a bolt that we had to drill out and re-tap, so that took a while. It took a good couple hours of grinding with a dremel and a carbide bit. I'm just saying I had the most basic tooling necessary and still got it done in about a weekend. I really enjoyed doing it, but I think I enjoy wrenching on a car more than the average person.

External wastegates seem to be a lot of hassle unless upgrading the turbo and you'll need a new manifold. There isn't really much room for it either. Hopefully someone can chime in if they have experience with an external wastegate on the stock turbo.