Twin Scroll Turbo

[tirediron]

most people don't realize dynos are all relative anyways. getting the most out of what you have is the point. awesome work dennis.

[Krizzie]

If you go this far with a project, knowing the numbers would be very high on my list.

Is the gearbox still standard!?

[squaab99t]

If you go this far with a project, knowing the numbers would be very high on my list.

Is the gearbox still standard!?

She will be back on the dyno to do some full sweep peak power measurements. I'll wait to do the steady state tuning when I get the new ECU installed.

Gearbox has been rebuilt by Scanwest. Shot peened 2nd, 3rd, ring and pinion. Quaife LSD, steel diff cover, and cooler with filter.

[sjones]

I think dynos are all about getting a grasp on the numbers and setting a benchmark .. on a track or strip ... or your daily commute is where you see the real results. I'd be in on the Dyno day to see what all the stupid attention I've spent to the stockness of my engine is actually realizing 115hp or whatever it is. ;-)

[squaab99t]

I think dynos are all about getting a grasp on the numbers and setting a benchmark .. on a track or strip ... or your daily commute is where you see the real results. I'd be in on the Dyno day to see what all the stupid attention I've spent to the stockness of my engine is actually realizing 115hp or whatever it is. ;-)

115Hp is better than 0Hp like most 99s are producing today.
Fantastic, I'll see what I can setup with the local shops. See if we can make a party/BBQ of it post the runs in their parking lot?
On the subject of Hp, the tax man was fair to me this year, so a box from Garrett showed up today. Went to a smaller more reasonably sized compressor and the fancy pants machined impeller. GTX3067. (Current is a GT3071R.) I'll reuse my turbine housing with no changes to the header or Downpipe.

[squaab99t]

Pulled the current turbo and did a visual comparison with the smaller sister.
Turbine impeller is the same. The change is on the compressor side.

Inlets
GT3071r

GTX3067. From what I have read it has the same external dimensions as the GT2860 disco potato. I suspect the inside is machined different for the impeller.

[squaab99t]

Rebuilding the turbo hanger stay this weekend. Primary reason is that the turbo ended up living more outboard than originally mocked up. This meant the tie rod had to kick inboard to reach the pickup point. As the exhaust system expands this will make the angle even worst. Need to add approx 7/16" to the strut and create new legs for the tripods. The other reason is to move the leg forward to make room for distributor plug hardware and eventually a hall sensor for the cam.

Progress. Cut up the old hanger to reuse the top buckets and threaded slug.
Kinda sucked cutting up being all nicely welded and powder coated, but you have to break some eggs to bake a cake.
Fabbed a new hanger plate for the compressor side as it is a different bolt patteren diameter.

[squaab99t]

This seems all too familiar. It did go quicker, but I still hate doing things over again.
Set the main horizontal first. Tacked the bucket first and then did some minor adjustment with the slug and then banged that piece down.

Added the other cam cover strut.

Final leg of the stool. A little wedge to close up the gap.

Black wrinkle powder coat for bling and anti corrosion factor.

Lots of room this time to put a wrench on the dist plug fastener.

[squaab99t]

Got it almost all put back together. Only a few more steps away from blowing up this gearbox.

I was having issues with sealing at the Vband flanges. When cold they would spit a mixture of condensation and exhaust peppering the engine bay. Went for a solution as RTV would not be up for the task. High temp RTV is only good for 500-600 degrees F.
Found this stuff at a shipyard where high temp and pressure fittings live. Mezzanine confirmed this is also the good shit they use at the wood mill.

That's right 1500F. The out gassing is outrageous as the solvents leave. Smelled like someone took the caps of a full box of Marks-a-lot perm markers. Huffing factor pegged.

[DrewP]

Wow. Is that like a ceramic in a binder or something? I'm gonna have to order some of that for work, for... reasons.

[hutch]

Awesome work, raising the bar as always!

Just curious as I'm (finally) getting your old DP ready to install. Did you use any of the hi-temp RTV on your old setup? Was the exhaust cool enough down by the cat? I was gonna pick a tube up for one of the non v-band connections but maybe I'll run a small bead for good measure on the v-bands too...

[squaab99t]

Wow. Is that like a ceramic in a binder or something? I'm gonna have to order some of that for work, for... reasons.

Elfin F'in magic stuff. It is black in color, tenacious and wets nice and smooth.
I got mine from a dealer in San Fran. Shelf life is not too great at 12 months and kinda spendy. 45 bones for a 5 oz tube plus shipping.

liquid type as the surfaces are threads of machined. The cement version is for rough surfaces.

[squaab99t]

Awesome work, raising the bar as always!

Just curious as I'm (finally) getting your old DP ready to install. Did you use any of the hi-temp RTV on your old setup? Was the exhaust cool enough down by the cat? I was gonna pick a tube up for one of the non v-band connections but maybe I'll run a small bead for good measure on the v-bands too...

Thanks. Just can't seem to settle for the standard hot rod industry.

I used RTV on the 3 bolt flange as the gasket had seen better days. The V-bands were all aft the engine bay and down low so I never paid attention to leakage.
The downpipe to turbine interface I did not use anything.
I'll put a squeeze or two of the Copaltite in a baggie and mail it off to you, as I will never use up the tube within twice the shelf life time.

"Final" setup for now and it drives very nice. Less lag and it just pulls hard.

[squaab99t]

Epic road trip and test yesterday. Pacific Northwest FB club was putting on a fun run in the Portland OR area. Put on 530 miles in a day with breaks. We set up a caravan of 3 to head from the Seattle area to Portland. 9-3ss, 9-5 combi and my c900. We were running a bit behind on schedule, so the 9-5 lead the pace to make up for lost time. Hand full of times we saw triple digits on the speedo. Glad to report no misfires or blown off hoses at the high loads and heat soaked conditions.
No evidence of cracks or leaks on the header and downpipe. The turbo hanger looks to be doing its intended function to support, but still allow growth from the heat and engine torque. The high coating stayed on and the sloppy Copaltite overage film burned away leaving looking like a super clean install. I am happy as a clam at high tide.
Fun run was bit wet but we still had a good time. The numbers: 20+ cars, 0 tickets, 0 fender benders, 1 break down. Quite a broad brush stroke of models, from a 96 to an impromptu 2nd gen 9-5. No 99s, I was very impressed with the 96. That thing held it own in the mountains and on the flats hitting 75-80 mph. He said it was a little bouncy at that speed.

Break down was a c900 '86. (the one above) Lost power coming off the mountain. I lead the trouble shooting. Traced it to the fuel pump not turning. I feared the worst with the '86 wire insulation. Hot wired it with a spare battery at the FP terminals, and still no turn. We resorted the folklore of beating the pump and I shit you not, it spun with the hotwire.
Then someone said let's rig up the battery to get her home. I suggested let's see if it starts without. Elfin magic, fired right up and off our way to lunch and beers

Word was out I had something special under the c900 hood.

[Nate]

A bit off topic that this reminds me of a Saab story.

We resorted the folklore of beating the pump and I shit you not, it spun with the hotwire.

When I was a teenager my dad and I were on a 35 mile trip home in his '80 99. The fuel pump was seizing and every couple of miles it would stop running. My dad would hop out and beat on the fuel pump as I cranked the engine over to get it going again. We were just a few miles from home when the car stalled yet again and and the fuel pump was refusing to run even with the persuasion of the hammer. With enough blows from the hammer and cursing it ran one last time.

Knowing we didn't have much time left and that I was at the wheel, I was ordered to drive it home and not to stall the damn thing! Being only 14, the pressure was on me, but I got it going flawlessly and we made it home.