Great build! I love the attention to detail and the planning put into everything, rather than just throwing parts together.

 

Sorting out the car:

A heat shield seemed to be blocking the twin scroll lever. Ground a section away.

Fixed a coolant leak at the heater core because I forgot to tighten the clamp.

Fixed a high RPM buzz, which was the fan contacting the fan shroud. The washers on the pulley caused the fan to not seat fully. Also the shroud just needed some adjustment upwards.

The car feels a bit quicker than stock. Spool appears to be the same as stock, it and pulls a little harder in the top end. The methanol system seems to be working correctly if I dial it to come on under wastegate boost.

Coolant temp is rock solid at 190F and the highest intake air temp I saw was 130F, at 80F ambient temperature.

AFRs are getting smoother, and closer to 11.0 under load.

Next up, I'm going to fill it with race gas (safety measure), turn on the CO2, and play with high boost. Please hold strong, clutch.

 

Car is driving nice. It is much more "lively" than it used to be.

Methanol comes on at 7-10PSI. The 150cc pre-turbo nozzle is cooling the charge 10-20C.

AFRs are in the 9s and 10s at boost. Will smooth them out. I'm finding the RTek gets a nice lean spike at the secondary transition, so I'll be adding fuel before the change, as well as leaning out the higher RPM area a bit.

The C02 boost controller is holding that wastegate closed. I have it adding something like 13PSI to the 2nd port of the wastegate actuator. I'm not sure it even opens.

Here is my boost plot. The falloff kinda disappoints me. I feel like the controller might have no more authority to raise boost. Flow restriction? I am on stock mufflers, airbox, and snorkel, after all.



AFM airflow numbers point to something like 230 WHP right now.

 

More data. Testing the stock airbox.

When I remove the top and change to a K&N square filter, we free up some filter and snorkel restriction.

Looks like that is good for about 1.5 PSI near redline.

 

The moment after a pull, peak intake air temps on the open box were 140F vs 127F on the snorkel. During the pull, there was no difference while methanol/water was spraying. Thank you, chemicals.

 

Another run. Stock with K&N filter element. A very small upgrade over stock. The air was 15F colder today, and I think that made the spool-up spunkier.



The extra PSI from the open box was my friend. I will probably go with a cone filter now, despite the stealthy looks of the stock airbox.

 

Keep in mind that a factory filter is about 99% effective at actually filtering out the dirt particles, and a KN filter is between 95-97% effective. 97% may see rather good, but consider the volume of air that an engine takes in and multiply by the efficiency. It adds up over time. Consider that at max flow of about 400CFM at WOT, that is close to 3000 gallons of air per minute.

After one hour, that's 180,000 gallons an hour.

99% 178,200 gallons of filtered air
97% 174600 gallons of filtered air
95% 171000 gallons of filtered air



This isn't to say that you are ingesting thousands of gallons of raw dirt and debris. I'm just giving you something to consider, especially since your engine bay looks so clean and stealthy.

If the gains are that minimal, consider just sticking with a stock filter.

Air Filter Comparison Study - GM Truck Central


K&N Air Filter Review - Debunking the Myths (and why OEM is better)



Now, KN on their website has a huge diatribe about why their filters are better due to increased flow, but with that much more flow comes increased chances for unfiltered air.

I personally recommend factory type filters, unless there is a good reason why a factory filter will not work. Such as a turbo swap, different induction tube, air box swap, etc. Many of us are forced to use cone style filters. Since that is likely the case, consider getting a filter sock for your cone filter, if you go that route. At least try and maximize your flow with the KN filter and minimize the dirt entering the engine, if you can

 

Yeah! Paper filters are really effective. I actually picked up an OEM filter for the build, and set aside the K&N that came with the car. I noticed that I could see specks of light shining through the K&N when I held it up to the light. The K&N came back out for the test to see what was on the table.

More interesting than the K&N is the open box airflow results. I'm still eyeballing the cone filter options. We'll probably see a cone filter with a heat shield on this car next season.

Also, I might have fixed a boost leak, so stay tuned.

 

I look forward to it. I will say, I wish my interior was a fraction of how nice yours is. I am still trying to restore mine, but if you would be so kind as to drop your car by so I can "borrow" your interior, that would be great.

 

Great looking car, nice work man! Makes me miss my TII AE...

 

I have no boost leaks. Nice and tight. No change in power.

I also checked the twin scroll operation. Working good. Here is my phone cam video, which might be interesting.

 

More Data:



Nice.

I made other runs with a trimmed foam air box, taking clean air from beside the radiator (I removed some foam to open a hole that goes through to the grill). It slightly lowered intake temperatures under load, but it increased air temps at cruise and idle, which I did not like. The filter is now completely open to engine air.



And this is the grill opening.

 

This is a Clarion 6 disc changer from the early 90s that came with the car.



It's on the fritz.

Time to fix it. That, or make literal mix tapes.



I searched on ebay and found a similar New-Old-Stock unit.













First, removing the unit from the storage bin.



It's bracketed to the floor and has cables running to the rocker.

 

Getting more intense.

All this junk needed to come out.



Diagrams of the equipment.



It was a professional installation before, so the wiring was labeled (thank you!).

The changer and controller were marked "remanufactured". I fished out my old manuals/receipts, and this bad boy was $850 back in 1993, which works out to $1400 today. $1400 to play CDs.

I put the controller box back where it was before (suspended from the speedo cable) and gave the speedo cable some reinforcement from above.



And now everything is back together, and a bit cleaner.






Plays nice.

 

wow, thats pretty retro, I like it

 

That is really awesome. I'm a big fan.

However, there is a lost art to making an old mix tape. I remember playing DJ between songs on mine. Ahhhhh the good ol days.

 

Added: Turbosmart 20mm Dual Port BOV and glamour shots.

I'm enjoying this valve. In 50/50 recirculation configuration, it has a modest PSHHH sound, and some comes though the intake as well. The car (RTEK) runs just fine in fully vented mode as well.









Unfortunately, my CO2 bottle is empty, and dropped me to stock boost. Anyway, you can hear the car.

 

so minty fresh! I love this car!

 

Jealous. How do you have such a clean car. Mine has slowly degraded in the past 20 years.

 

A friend of mine thought he spotted my car at the automotive hall of fame cars and coffee a few weeks back but I have a feeling he may have spotted your car.

 

That was it! I'll start bringing it to more autocrosses when I get the clutch beefed up (winter project).

 

I'm having a vac leak issue that is keeping my idle wonky otherwise my car is good as gold. I tried autoxing last summer and it did okay but my diff is too tired and its like an open diff. be sure to do your differential clutches when you do your clutch and when you do your clutch get an AL flywheel - it wakes that sucker up!

 

Any updates?

 

Yes! Did things this weekend in the warmer weather.

- - -

Ut oh fan. This needs attention.



Found a 60k fan from tarmac13b. The hub has been evapo-rust-ed and Por-15-ed.



Onward to clutch fixing.



More doing.



She's a beaut. But very very oily. I'll be looking at all the seals in the area.

 

The cleanliness of this build is insane. Awesome to see a build mixed with quality and patience. Definitely subscribed!