What a perfect way to bump this thread to it's fifth page by adding some dyno numbers! I was fortunate enough to get on the dyno this past Friday and finally have some idea of how much power this car is making (but that's not quite the full story, we'll get to that).

Over the course of three sessions the 12AT was putting down a pretty consistent 236 WHP and 201 ft-lbs of torque, not too shabby for a little ole' 12A and is right about where I was expecting. Dyno was a Mustang brand for those who keep track of such things. Everything went smoothly and it was honestly a great first experience having a car on a dyno. Had it done at a local community college during one of their training days - basically my car got to be used as a "mock customer vehicle" for the students to do their inspections and dyno prep on. Having it up on a rack was nice too and with the eyes of seven or so folks on it was great to have some confirmations on the overall condition of the car (my pinion seal leak seems to be getting worse for one). Here's a few photos from the day as well as the dyno plots.









So all in all pretty solid and a great day overall, but here's the kicker. I didn't actually do any tuning while I was there Friday, but I did collect some data logs. That evening I was going through the data and noticed I wasn't hitting my boost target (not terribly uncommon for this car) and decided to dig deeper. I've always had trouble hitting my boost targets and especially holding them out to redline on this setup so this wasn't a huge surprise but it was a little disappointing. Figured it was worth looking into though and I ended up getting so hyper-fixated on figuring out what might be going on that I whipped up a quick boost leak tester on my 3D printer and ran to the parts store to grab a valve stem for it (pictured below). About 15 minutes and a full air compressor later and voila, a massive boost leak. It was on a clamp that I probably hadn't touched since I first boosted this car three years ago and it was absolutely spewing air. Fixed that and one other minor leak that evening and came back the next day to find the car, 1, building boost 600rpm sooner, 2, over-boosting significantly, and 3, wanting up to 10% more fuel under boost in some areas (which also ended up fixing a weird dip in my VE table).



A bit of fiddling with the laptop later and the car is now holding my 12psi target to redline reliably, power is smooth as butter, and this thing is darn quick (relatively speaking). If my all-seasons aren't warm enough I'm pulling the tires loose at the top of second and chirping third. Reached out to the guy who runs the dyno and the plan is to have it back there on the 21st so we'll see how much of a difference that leak made. Also for further context, on the dyno runs pictured above it wasn't even holding 10psi plus the inefficiencies from the leak over-driving the turbo. While I don't expect the new numbers to be massive I would easily bet we'll be north of 250 HP now and that's the number I really wanted to see. Certainly very excited and also can't believe I probably had that boost leak since day one...

To wrap up, the real reason for the dyno runs is that I want a "before" number to compare with once I get the new intake manifold on. Progress is still being made there it's just slow, but the dyno was one of the last big steps to getting the car ready for it. Also I got some videos of the dyno session so I'll perhaps upload one of those so I can link it here. Anywho, with that here's one last photo that I thought was sort of fun (friend caught me doing some tune adjustments). Cheers!

 

Curse you for making me think of power output. I'm also a little upset that our community college has no dyno. That said what a great opportunity. Leak testing is something I should do as well. I do have a question, I'm surprised to see vehicle weight as 2750 lbs. Is that off of a scale? I weighed my old 83 back when and it was around 2300 lbs. Looking forward to the update on the 21st.

 

Haha, so how much power will your SA make, Richard, hmmmm? (probably more than my little 12A)

Funny you should mention the weight, I never even noticed that. I don't believe it's from a scale (especially with how round that number is); I'll have to ask when I'm in there next. I would certainly hope my car doesn't weigh that much, although I'm sure it's got some amount of weight over stock between the turbo, EFI, subwoofer, surge tank, etc. Over 400lbs though, that seems like a stretch.

The fact that the local community college has a dyno is truly a blessing, granted they've also got a wicked automotive program so it's really no surprise. Come May of each year they do a two day dyno event as a fundraiser, 3 runs for $50. Not bad if you're nearby. This year it's running May 16th and 17th at their auto tech facility in Lebanon, OR.

 

My projected power, is a theoretical wet dream. Brian advertises his BNR turbo a 65 lb/min. Which if you use the Howard Coleman figure of dividing by 1.3 implies that it’s good to 500hp. Which is wonderfully optimistic. The compressor map I found has me in the 35lb/min at 7psi. Which is what my wastegate is set for. So 270hp as an optimistic estimate. Although I expect it to be lower. Just based on dynosheets I’ve seen over the years. Maybe a 230hp at 7psi. As part of this academic thought experiment, 14psi I could see up to 380hp. Which is just to me is a comical amount of power in a street driven car for the age and weight. In all honesty, if I can dial it down to 200-250 hp on the road and bump it up to 350-380 for special occasions, I’d be happy. A lot of my overdoing my car was not to make 400hp, it’s incase I accidentally make 400hp.

I always thought you were going to have a higher peak hp, but I’d have a broader torque band.

the dyno day is on my calendar, and I am following on the auto programs Facebook page. Seems like a good deal for a great cause.

 

That certainly would be a lot of power at those theoretical levels, but I agree it'll probably end up in the mid 200s especially if you're only running 7lbs. With a little more boost I'm sure you could easily hit 300 though.

Eventually I do plan to swap to a different turbo (likely a Borg S362 or S363-SXE) and then my goal is around 350HP at full beans. I built the engine to hold 400HP pretty safely so if I can make it into the mid 300s with that setup I'll be plenty happy (and probably a bit scared for my life behind the wheel). Before that happens I need to get the intake sorted and then the exhaust redo and turbo will happen at the same time. Not so sure I'd have a higher peak number though, what rpm are you spinning your engine to? My limiter is at 8k but I rarely go much over 7.

It would certainly be awesome if you're able to make it down for the dyno days. Our two cars are so different and yet also humorously similar; it would be a lot of fun to have them in the same place.

 

Finally got the couple of dyno clips uploaded, they're as a YouTube short format but it works well enough.

 

So it's been a little while... I didn't realize it had been so long actually; in fact I didn't realize I never even shared my exciting intake manifold news - it exists now!

First and foremost, the car is still driving as always, although the last few months it's been a little neglected (bought a new daily - an LS400 - with a blown engine, I think that sums up where my time went). It's been to AutoX a couple times now, it actually ended up making 250HP on the dyno (on the old setup with a boost leak still), put some proper sticky tires on and did some canyon carving, drove the car 600 miles to San Francisco for 7s day (what a trip), and more.

Now the exciting stuff, the new intake! It took over two years, some lucky connections, and a lot of work, but the SA finally has a one-of-a-kind 3D printed intake manifold made specifically for the 12A!! After a lot of design iterations I ended up with a "short" runner design with a standard plenum using the same electronic throttle body I had been using previously. The manifold itself is 3D printed out of HP's MJF Nylon-12 plastic and uses a machined aluminum mounting flange that bolts the whole thing to the engine and also houses the primary fuel injectors. The flange was partially me being paranoid about the reliability of a purely plastic intake (which now is less of a concern given experience) and also a hold over from a prior design that used an aluminum frame for rigidity (now it just uses two strut bars). The whole thing came out beautifully, definitely lets the top end breath better, improved drivability, and prettied up the engine bay nicely. I'm sure it's making more power than before too, and the top end is noticeably smoother and just keeps pulling (the turbo is actually becoming a limiting factor now). It's been on the car now for almost six months I think, with thousands of miles and hundreds of hours of driving with no significant issues. But anyway, enough talk, here's some photos





















So yeah, the next evolution of the car is finally here and I'm so incredibly happy with the outcome. Next on the list is some interior rust repair and paint (car is coming apart in a month or or two in theory), and then there's the same old "to-do" stuff like better brakes, a steering rack conversion, rear end, transmission, and of course, a bigger turbo . Project cars truly are never finished, and this one certainly never lets me forget that.

'Till next time,
Cheers!

 

I’m near speechless. I want to acknowledge the work put into this. Simply amazing!

 

Amazing project!

 

I saw this car in person at a local autocross a few months ago. The 3D printed intake came out very well and might even look better in person. Good material/color choice as I think most people that saw the car that day probably thought it was cast aluminum unless you told them otherwise or they started looking closely. I was in a different run group and didn't get a chance to introduce myself unfortunately. Oh well, there's always next year.