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After some back and to with Todd we were able to get the AFR's just right. Todd wasn't happy with the data the shop was sending him- he kept saying something didn't add up and he was right. They spent a day smoke testing the car and tracking down any rogue vacuum lines. Blocked off all vacuum and tested one by one. There was a major leak on the brake booster > TB elbow port. Blocking this changed the idle/cruise ratios from around 19:1 to about 16:1/high 15. Huge difference. At that point we had the AFR's on WOT absolutely perfect so Todd was able to simply some fuel to the idle/cruise ratios to rich it up. 993's usually run nicest in the 13.8/1 range which is slightly below stoich (14) which is where Todd put it.
It's putting down around 360hp at the wheels or 420hp at the crank- that's with the slightly smaller crank pulley, mocal intercooler setup, Fabspeed cross-pipe and Supercup mufflers.
It's been 3 months since I last drove it so taking it out for the first time was a strange sensation! First impressions are that the power delivery is extremely smooth- you don't really feel the boost coming on, the power is just there. The noise is incredible- the high pitched supercharger scream over the flat 6 is unlike anything else. I have never driven a 993 Turbo, but I can't see how they can be better than this. I can easily break traction now in gears 1 and 2 over 4k RPM and I can in 3rd too if I abuse it- that will take some care to readjust as before, when it was NA, it was pretty idiot proof- I have Pilot Sports and they just griped in corners, now with the extra power I can slide around at will.
Couple of things will need adjusted- I'm getting this really weird whistle coming from somewhere. Very loud and gets louder with revs building. Shop thinks it's related to the ISV- it's much more prominent on cold start up when the ISV is activated and fades away to a background whistle when warned up. If you were to squeeze the pipe / tube feeding the ISV it goes away, so it's like a resonance thing is causing it. I may just get a new ISV to be 100%.
Also, the Supercups are intolerable- at WOT or even 50% throttle they sound amazing. At partial throttle or idle the boominess is unbelievable. Like, need earplugs bad. If anyone wants them let me know! And I'm on the look out now for some Fister 3's again as I sold mine, darn it. And my muffler tips.
Last thing is the carbon Cobra seats are coming out- they are very nice but they don't have tilt function to give easy access to the rear seats which I want, so I bought the Recaro A8's that were for sale in marketplace. I'll post up next week when they go in.
Wow! 420hp is a serious number and your power to weight ratio is better than an OE Turbo. Looking forward to seeing it at Radwood. I will have my lightly modified 993TT, maybe we can compare notes.
The shop made a video of the dyno run- thought you might like to see it. We were struggling with AFR's and detonation at this point so it was *only* making 336 WHP / 393 HP at this point...
@haygeebaby Boost is 6psi; it runs up to 10psi then quickly tapers down to 6psi and holds to redline. The temperature differential between pre and post intercooler is something like 20 or 30 degrees F from memory, can't remember exactly.
Glad to hear you got it sorted! Kudos for taking the path less traveled, the results are clearly worth it.
I’ve been impressed with the TPC SC when combined with proper tuning. Protomotive has really helped make this kit a viable performer. I know it’s not a very DIY friendly process logging/tuning but the results as well worth the effort. Again Kudos for the hard work getting this dialed in!
Post a dyno sheet when you get a chance. I bet it has a fat power curve.
Now that’s the real story! Look at all that torque (damn near 300 wheel torque) from 3.1k on to 6k+, that’s what make the SC soooooo much fun to drive!
If you are running 10psi and tapering down to 6psi then your pulley setup is rotating the M90 unit at a far greater RPM than the stock pulley setup.
Stock you will see 6psi max and tapering off just around 4psi at the top end.
I don't think I saw my unit do 10psi with the 4" pulley setup with the heat exchange unit. The 4" pulley maxed out the efficiency of the M90 unit. Which meant it started to generated a lot more heat and little power beyond that.
With no heat exchange unit, i.e. pipe straight into the manifold from the SC - I saw 17psi with the 4" pulley. Good times for sure.
If I where in your shoes I would be happy with 10psi. I probably would call it and be happy with that amount of boost.
Touch wood - but when you start running more power - a good amount in this case - other things start to take their toll and can potentially become expensive or increase garage time for the car that you just want to drive.
Did you get any telemetry gear for your car so you can keep an eye on the Boost figure, IAT, EGT, and AFR?
Would be nice to know when something is off so you can diagnose and fix before bigger problems occur.
Any plans for Meth injection for cooling purposes only?
I found it a great addition and gave me a piece of mind. It dropped IAT's a good amount when boost came on.
Injecting meth will also help avoid detonation. If you go down this route - inject pre throttle body.
For your charge cooling system - did the garage install a drain tap to drain the fluid?
This is a handy feature for when you need to remove the charge unit to access parts of the engine.
Did your garage fabricate a better throttle cable support or did they use the stock "L" shaped bracket?
I didn't like the stock version and we ended up fabricating a better one.
Also - your car looks great in the vid. Enjoy and drive safely bro.
The gen 3's have a 100k mile plus oil change interval, I looked into it but decided against it.
It is running lean in the graph you are right. That graph was before we dialed it in, we were struggling with the AFR's. At that time. Todd recommended taking readings from street driving as opposed to on a dyno so we completed the tune by logging runs off the dyno.
On WOT it is perfect- drops down to 12 or so. Plenty fueling.
On your other point about the pulley- the pulley on the super is smaller yes, but it's not over-driving it because the crank pulley is smaller too- changed for the Clewett system. It sits about 6psi. How are you measuring yours?
Boost guage. I ran Zeitronic gear. I had sensors for boost, EGT, AFR, and two temp sensors.
there are lots of options for boost guages. The market has probably changed heaps since I was shopping for them.
02-26-2020, 12:40 PM
