North American Turbocoupe Organization

Hey guys,

I am new to the group, but not to the car.  Long history short, have owned 5 87-88 TC's over the past 25 years.  Also with a few Supercoupes in the mix.

My latest is a '88 5 speed that I bought 5 years ago.  Pretty much drove it home and parked it.  Finally getting around to some much needed TLC.  I was just going to replace some heater hoses so that I could drive it again.  Well...

I have torn it down and the head is about to come off.  Now planning to just pull the engine to easily replace oil pan gasket and get at the leaky rack and pinion/entire power steering system fixed.

My main question is, if I am planning to keep the factory IC on top, what is the most HP gain I can get.  If that is my plan, what's worth doing and not doing?  Should I really beef up the bottom end while it's out? Or just have machine shop check it out and fix what needs fixing? 

The easy to get to stuff I'm not really worried about, I can always change that later.

Not a daily, but want it to stay reliable and just a fun weekend car.

Things I already purchased/planning

Oil Pump
timing belt
all gaskets (obviously)
All new water lines, pump, thermostat, radiator
plugs, wires, cap, rotor, coil

I got the XS-Power tube header. Didn't realize it was china, so might be changing my mind, but it came in and seems pretty nice?
Stinger 3" exhaust turbo back with magnaflow, no cat right now?
Stinger Oil Lines
EGR delete?
Remove Factory AirBox
Clutch Kit, Just got an OE replacement, but thinking I might have gotten something a little better?


Not at the moment but soon
Walbro 255 and filter

I know most of this is covered in the thousands of post on here.  So I guess what I am asking is how restrictive is the Factory IC and if I don't want to do a FMIC, do I really need to worry about engine internals?  Probably will never replace the ECU, but I guess I should never say never.  

Is a bo cam 1.5 worth it? Should I port the intake?

I've read the T3 with A/R .48 is comparable to the IHI, with some improvement, but I assume this would need to have FMIC to be worth it?

Sorry for the long post, I know I am a little all over the place.

***** EDIT **** Actually I stumbled across the stinger FAQ and think I got most of my answers. But I'll still take any input you guys have.

Thanks in advance for any advice.
Adam

The problem with the factory IC is its position directly above the very hot turbo. During low speed driving or car stopped, the IC gets heat soaked by the turbo, becoming an "inter heater". Other than that issue, the stock IC is a half way decent unit. 20 years ago, I mounted a 6 inch diameter Spal fan with a home made shroud under the IC to constantly pull cool air thru the IC via the hood vents. It has worked very well, and looks totally stock. Even on a hot summer day after the engine has been running at operating temperature with the car not moving, my IR thermometer shows the IC is only 15 or so degrees F above the ambient temperature. Several years later I designed and built a temperature controller for the IC fan so it only runs if the IC outlet temperature is above a given temperature which I usually set around 60 deg F. I did this so the fan only runs in warmer weather to hopefully extend the life of the fan.

That's a pretty nifty idea with the fan Jeff! Does seem odd to have something with cooling in mind so near the turbo...I like this idea because I would prefer to leave the IC in the stock location. Would love to see a pic of the setup if you are ever working in there!

Acro,
If you want to keep the factory TMIC, you could buy a nice turbo blanket to keep some of the heat from radiating directly onto the intercooler, also, those headers are very prone to cracking, I would simply take your factory E6 manifold and give it a good porting. These will make good power at your goal level. I would also change your fuel pump before doing anything power wise as the factory 88lph pumps are not up to the task. A simple and fun build is to keep your IHI as it makes near instant boost and is a great street turbo with its super quick response. Change the fuel pump to a 255lph, remove the factory airbox and mount a K&N in the fender well, not directly on the VAM as that is on the hot engine bay. Change the factory downpipe with a Stinger 3", no cat is best, but might not be legal for your inspection purposes. I would not delete the EGR as on the street, they work well. Get a gillis boost valve and set it at 18psi with the IHI, which is about max you want to spin it. I also would not port the intake in the typical gut the upper and bullnose the lower as with your stock head it would not be hurting you. Maybe find a Ranger roller in the JY to get you some nice factory roller rockers and a great torque making cam for the street, which is a great match with the IHI as both the cam and the turbo would be out of breath around 5500rpm. with this set up you would have a great running fun car with great drivability. Also, look into changing the factory mufflers for some straight throughs such as magnaflows or maxflows.

I've got the cone filter attached to the VAM, I would like to move it it out of the engine bay, but I don't see how it is you guys get your filter in there. What am I missing?

Rob,
I followed this general plan linked below, my 3" rubber hose is very stiff, but it works well and holds everything together.

https://turbotbird.com/thread-k-n-front-mounted

I used some 3 inch PVC elbows and 3 inch rubber couplers from the local hardware store from the VAM thru the inner fender to the K&N cone in the fender. Cost maybe $15 total in parts.

I like the PVc idea, I may have to try that instead

I painted the PVC pipe Ford light blue so I didnt have to look at the plain white PVC pipe every time I opened the hood. Also put a PVC bung in the PVC pipe for the hose from the charcoal cannister. Gotta keep those nasty gasoline vapors in check!

I'll have to go take another look at it. That is the write up I was looking at the other day when I was thinking about doing this. I was down where the write-up said, I didn't see anywhere that looked like I was getting that cone filter in. I'll admit I didn't attempt to cram it by distorting the shape of the filter. Maybe that's what it takes? I'll go take another look after work.
I don't know a lot about these filters, but I expect I would need to clean and re-oil at some point. Do you guys do that inside the bumper now? Or do you take it out now and then?