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Well I have been chasing an exhaust leak. I think it is coming from the exhaust manifold or turbine housing.
I found a crack internally, and that's enough for me to replace it.
crack in manifold. I am sure there are more.
Since I am replacing the manifold with a MAP cast stainless one, I may as well pull the turbo and swap it out. It has almost 20k on it, and has held up fine. (see going ghetto kamak thread in post #1). Now I love my 20g setup (except it is quiet) and so I have decided to pretty much run the same turbo but with a 7+7 blade configuration with a 73mm extended exducer!!! (yeah I didn't even know that existed).
building a swap-in spare 20g and replacing my cracked manifold.
Guess which is stock
Sticking with 9 blade TD05. Love the quick spool but better top end flow.
Rebuilding OEM CHRA to a 20g
Ready for VSR balancing.
The CHRA shipped to pureturbos for balancing. This is the second time I have used them, and they do quick & good work. They provide a before/after balance sheet and you can call them and a HUMAN answers.
So the short term plan is to swap out the turbo and to replace the exhaust manifold with that cast stainless beauty.
When it gets warmer I will put in the CSF radiator and fuel tank starvation solution system for track events (linked in post#1).
I will post the balance sheets when the CHRA comes in. The wheels are individually balanced, so I am curious how much it needed to be right.
1.) Replace OEM exhaust manifold with MAP stainless cast manifold
2.) Replace 11blade 20g turbo with 7+7 20g turbo
Spring plans:
1.) Install CSF radiator
2.) Install Derale 25 row oil cooler
3.) Install custom designed fuel supply setup (uses radium fuel hanger / cup) - linked in #1 post
Watkins Glenn - HPDE !
I haven't been racing since I traded my Z06 for the Evo X MR in 2012. I knew the car wouldn't be what I wanted stock. Too many reviews about SST overheat even STOCK. So its been a while since I have been on a real track (1/4 mile is fun, but not really RACING in my book).
I have literally no pics of my car. When a picture is taken it's by someone else, documenting something that could end horribly. In this case, racing my brother in our yearly grudge match. I won 2017. 2018 he is threatening more changes, but perhaps this manifold and turbo swap will do more than correct my exhaust leak!
I got a private message asking about this 20g (11 blade GTX style compressor with 9 blade TD05 turbine), and what was the best power it made.
On FULL BLAST (with knock you really shouldn't ignore) it made 432hp to the wheels. This is with a 220hp (SST) baseline in VD, on 93 PUMP GAS. No meth. No E85. I am limiting torque to prevent stock SST clutch pack slippage. If the clutch packs give and slip it ruins them. I have had it slip ONCE around 330 lb-ft and they were not 100% warmed up (150F). The clutch packs do some ridiculous limited pressure nonsense to attempt to warm up when under 130-150F, and with high torque they give way. So I always warm it up first, I have a gauge mounted that reads the SST fluid going into the liquid-liquid cooler/heater. When that reads 130F or more, its go time!
Here she is:
I am wondering what the larger exhaust runners (MAP manifold) and compressor change is going to do. I am not TRYING to make more power, but lets see what happens. The 7+7 is extended tip to 73mm. The current 11 blade is extended to 71mm. Turbine is the same, everything else is the same.
Edit: I see in your old thread it originally was $100. Not too shabby.
For some reason the total was $103. That does INCLUDE the return shipping cost. It was $32 for me to send from NY (about as far as you can get from CA), with insurance and signature. They include a before/after balance. He told me on the phone the balance was WAY out before the worked it over. Almost at the limit of the machine. The wheels are both balanced by themselves, but they do the entire CHRA via VSR balancing. What I like is that when I assemble the turbo you use assembly lube, but to balance the CHRA they have to pressurize and put fresh oil through the assembly.
Before even getting into the turbo/manifold swap out, I noticed something horrible. The MOCAL fluid pump for my SST had died, in a horribly leaking/spraying manner. So I had SST fluid everywhere, and an unknown amount in the actual transmission left. If this pump had died this way on the track, someone could have been hurt. I decided to rip everything out and go simple. No electric pump, power relay, no thermostat, no SPAL fan (it was so gunked from NY crap roads I am pretty sure it would just pop the fuse if it ever tried to run), no SST temp gauge (accessport now reads SST temp anyhow). The new fluid loop will be stock cooler -> front cooler -> liquid cooler. This will be pumped via the stock built-in mechanical SST pump. Road/Race engineering has had good luck NOT installing a separate electric pump. That pump was 180 bucks, and is just out of warranty by a few months. Lame. I knew adding something like that was just asking for decreased reliability.
So removed parts are:
try to keep SST cooling simple
With the new loop it goes like this:
1.) At 150F the OEM built in thermostat sends fluid for cooling
2.) Stock cooler cools
3.) Front mount cooler cools
4.) Liquid cooler will cool OR it will bump the temp UP TO a max of 180F
I can't imagine with how viscous the SST fluid is, for there to be too much pressure buildup. The liquid/liquid cooler is also supposed to have a very low pressure drop.
The turbo was pulled, and manifold. The new 20g CHRA was built up with everything except the turbine housing. I have the classic stuck studs on the housing, and once those are pulled I can put everything back together. Work monday. Tick tock. Tomorrow morning the torch comes out.
I dropped the OEM cooler out of the loop, since RoadRace had only ever done TWO in series; not three on the OEM mechanical pump circuit. The 7+7 turbo spools real quick. Since it isn't apples to apples (due to the MAP manifold change) it is hard to say what did what. But the low end kicks hard and my WGDC is LOWER than it was before. So it is making more power with less boost.
20g flavor of the week
When I have the time I will post the VD graph and we'll see what's what.
So as I posted above, if you read my SST custom cooling thread I designed and built a cooling system that was a little too complicated. After the pump failure I ripped out a ton of stuff:
Removed:
1.) Improved racing 150F thermostat that controlled coolant to Mocal liquid/liquid heat exchanger (theory was to allow car to cool up before sending coolant to be heat exchanged with SST fluid).
2.) Derale: 180F thermostat to control SST fluid to front mount cooler
3.) Derale: inline fan controller
3.) SPAL SST cooling fan (on OEM cooler)
4.) Improved racing NPT block to measure SST fluid
The new loop is simple and direct. SST fluid travels from filter housing (built in 150F thermostat) to front mount cooler and then to Mocal liquid/liquid cooler. That's it. Two coolers (not three). No pump. No relays. No control switches. No external thermostats.
The result is what is interesting. It is heating up as QUICKLY if not quicker than with all the other stuff I had in place. It heats up exponentially. I think this is because as it goes over 100F and the internal thermostat starts to open (full open at 150F), it sends MORE SST fluid to be cooled where it is actually HEATED (driven to 180F by Mocal cooler). So it takes off and heats up better than with the dedicated electric pump.
I have to remind myself: keep it simple stupid (KISS).
OK finally getting around to tuning the new setup. The main changes being the MAP stainless exhaust cast manifold and a 7+7 20g vice 11+0 20g compressor wheel.
Just to make things more complicated when I was changing the SST fluid cooling loop (removing pump, using mechanical instead), I changed up my air intake. I am using a COBB turbo inlet adapted to an Apexi aluminum MAF housing and filter, mounted in an AEM airbox. I simply did this because the Apexi intake is so friggin loud even with a re-circ'd BOV setup (synapse unit).
Given all these changes, I knew I had to change up the MAF, and MAP values at a minimum.
So the MAF curve I was using was NOT smooth. Instead I let the values define themselves and this caused some lumpy (but not jagged) values in the MAF curve. This time around I think I am going to stick with a proper MAF smoothed curve and mess with the VE tables if need be.
For the MAF and the MAP two days each of to/from data was acquired with wideband (2hr+2hr). Total samples was around 62k (x2) in each mode in closed loop vac, and around 1.5k (x2) samples in open loop boost. The MAF curve is easier to tune since it is just a 2d curve. The MAP table is a trickier beast, and so my coverage was not as good as I had hoped:
Glad I read your thread and your recommendation of pureturbos! I don''t seem to have anyone locally that can do it and $100 + outbound shipping is not a bad deal!
Sometimes I wonder if ANYONE reads this build thread!
What I like about the VSR balancing (besides that it is balancing the entire unit) is that fresh oil gets run through the turbo. So your assembly lube and hopefully anything else that shouldn't be in there is flushed out before you go bolting it into your car.
Jan 31, 2018, 01:43 PM
