93' Road Racer Build

[jdwertz]

Quick question for those no longer running a charcoal canister. I plugged the nipple on the fuel filler neck for the line that goes through the roof and removed the charcoal canister.

Now there is a lot of pressure building up in the gas tank. Did I plug the wrong nipple or is my gas cap bad?

Your gas cap is working too well. There is a diaphragm valve on the cap that must be defeated for the tank to breath out. Not the best for the enviro. I was actually thinking of putting mine back. I have lingering gas fume smell after the car sits over night. I need to wire the canister valve back into the ecu or run it of the ignition switched power.
Your car is looking good btw.

That is what I thought. I have noticed the gas fumes sometimes when I am driving. Maybe I will wire mine back in as well. It is just so nice having all that extra space in the inner fender.

Thanks for the info and compliment. Unfortunately this car is a bit messy now, I had to DD this for a month though the snow and mush while I fixed my wagon. Hopefully the fresh powdercoat I put on everything is not too ruined.

[squaab99t]

I was thinking about relocating it to aft of the left front wheel well. Then run a tube up to the intake.

[jdwertz]

I started pulling the car apart for the Holset and 9k brake upgrade. I need to decide on orientation for the Hy35, either mounted in the stock location or turned 90 degrees. In the stock location the compressor housings hits the head so I would need to add a spacer. If I add an elbow won't that add extra impediment to the flow? Anyone have thoughts on this?

[squaab99t]

I started pulling the car apart for the Holset and 9k brake upgrade. I need to decide on orientation for the Hy35, either mounted in the stock location or turned 90 degrees. In the stock location the compressor housings hits the head so I would need to add a spacer. If I add an elbow won't that add extra impediment to the flow? Anyone have thoughts on this?

Any time you add bends to the run it adds resistance to the over all system. K factor for the folks who remember your fluid dynamics. The exhaust pulses will not have the same distance to travel with 90*. Inside curve versus outside. In this case will it make a difference? Upper end no, but a turbo that size the less factors contributing to the lag the better. The other thing to adding a 90* is how you are going to support the turbo now that it is cantilevered further off the OEM support common to the gearbox bracket?

Barring rebuilding the manifold to move it further forward, I would suggest adding a spacer that matches the inner dimensions of the turbo housing flange and not the 90*fitting.

[Jordan]

I'll also add the comment to Dennis about how this will also change the orientation of intake plumbing, probably for the better, but I don't know which is better for performance. It'll also straighten out the downpipe.

[DeLorean]

Well, I can say this... You can now get fans that are about 1/2 as thick as the original Bosch or AC-Delco fans that move ore air. If you do space the turbo out from the manifold and start getting fan interference, that much is easily correctable, and for much cheaper than OEM fans. As for adding bends, I would not worry about it. You gotta work with what space is available...

[jdwertz]

Thanks everyone for the comments.

Positioning the EWG for optimal flow is an another factor. With the 90 degree option I would be able to move the EWG flange to a more optimal position.



It seems like this is 6 one way, half a dozen the other, each option has trade-offs.

[squaab99t]

Thanks everyone for the comments.

Positioning the EWG for optimal flow is an another factor. With the 90 degree option I would be able to move the EWG flange to a more optimal position.

It seems like this is 6 one way, half a dozen the other, each option has trade-offs.

That is how packaging usually works. Trade offs and compromises. You need to figure out what is most important to you and then work around that.

[jdwertz]

Updates!

9k front brakes finally done. Still working on completion of the abs removal. Question for those knowledgeable: The ABS system in the later cars has only one hard line that runs through the cabin. Whereas the non abs has two, one for each rear caliper. Does the master cylinder in the non-ABS push enough fluid to only have one hard line that runs both rear calipers?

[paulh]

If you did it that way, you'd have to either splice the two front calipers together, or have a 3rd port on the master cylinder. Also, your brake bias is gonna be all screwed up. The correct solution is likely going to be to run a fresh pair of lines to the rear and plumb it up diagonally split like the factory intended.

Paul

[Jordan]

The bias shouldn't be screwed up, the master is the same bore for both the front and rear.

[jdwertz]

If you did it that way, you'd have to either splice the two front calipers together, or have a 3rd port on the master cylinder. Also, your brake bias is gonna be all screwed up. The correct solution is likely going to be to run a fresh pair of lines to the rear and plumb it up diagonally split like the factory intended.

Paul

How would they get away with this on ABS cars then? I would think you would want independent control of each wheel with an abs system?

Just from a quick google search the 900 has a three-channel, four sensor system, with only one valve to control both rear wheels.

[paulh]

The bias shouldn't be screwed up, the master is the same bore for both the front and rear.

I'd think it would be a bit not right though, since you'd have the two smaller pistons in the rear on one channel, rather than one small rear and the larger front on each channel, but brakes are confusing. The ABS in the 900s was a 3 channel system, so it could control the fronts independently, but the rears got modulated as a pair, hence the single line.

Paul

[jdwertz]

I started playing with my new welder and experimenting with various metals. I started with aluminum based on the advice from Jodi on weldingtipsandtricks and then moved to some steel. I have a lot to learn and a long way to go before I can start making my exhaust.

I need to make a better table to weld on or at least have a chair to sit on! I was mainly focusing on just playing with the settings and getting comfortable with how many amps to put through various thicknesses. I am newbie so don't judge too hard. 3/32 tungsten 3/32 ER70 rod. Gas was set to about 17 cfh.

[Jordan]

I think if your just starting out, Steel will get you over the basics easier than aluminum which is a lot more nuanced. Aluminum will certainly hone your skills more , but I feel like the starting out is hard enough without having to deal with all the curve balls aluminum throws.

The non abs system uses a twin master which I think are 7/8"? bore and a booster which I think is 2:1. The abs system uses the accumulator to boost pressure. On my '91 (ABS) I swapped in an '87 rear axle to use the older style brakes/hubs.