The 24 Hours of Lemons Forums → Lemons Tech → Eyesore Racing dyno charts
I just dug through our dyno testing file and assembled a horsepower-by-horsepower history of the Frankenmiata. There are a lot of good lessons in this story for any Lemons racer willing to learn:
http://www.motoiq.com/magazine_articles … ealed.aspx
-Dave
Well I, for one, read thru the entire thread. Really interesting and a must read for both Miata teams and, I think, anyone wanting to run Lemons. It's a great primer on what it's like to run a car for several seasons.
Great article. Glad I don't have delusions that I'll ever actually ever have a competitive car. But it's cool to see strong, serious efforts like your team's rewarded. Be sure to do a writeup of "things we learned at LeMans and will apply in our Lemons campaign" too. Or maybe, "How my garden sprayer won LeMans for Audi"
Of course, the only reason you're sharing this is most assuredly because you have something that far surpasses the potential of the miata in its current state.
Can't wait to see it.
i think the big lesson to learn: i need cooler friend. one's that have dyno's and mexican turbos and crap like that.
excellent write up once again Dave. You do a great job of making spreadsheets fun.
i think the big lesson to learn: i need cooler friend. one's that have dyno's and mexican turbos and crap like that.
You ain't kiddin'
From a Feb 2009 article linked in this one:
Eyesore Racing's six-man team boasts three turbo engineers, two automotive journalists, two professional test drivers, two marketing professionals, a biomedical engineer, a rocket scientist, and insiders from both Nissan and Mazda.
Great article. Glad I don't have delusions that I'll ever actually ever have a competitive car. But it's cool to see strong, serious efforts like your team's rewarded. Be sure to do a writeup of "things we learned at LeMans and will apply in our Lemons campaign" too. Or maybe, "How my garden sprayer won LeMans for Audi"
Of course, the only reason you're sharing this is most assuredly because you have something that far surpasses the potential of the miata in its current state.
Can't wait to see it.
They're going w/ the NOS button.
Eyesoreracing.. You guys have dyno tests, but you're probably really not seeing what is going on with your car. Have you looked at on-track mid-race data? I wouldn't be suprised if your getting considerable heat soak, and are losing power after about the first 20mins.
Several dedicated Miata enthusiasts have spent countless hours trying to figure out cooling and reliability for turbo-d miata engines. Many guys have had issues with a drop in power with stock cooling in as little as 10-20 mins. So you may have picked up considerable HP on the dyno, you may not be getting that on the track.
Before you increase boost, or fuel, adjust timing further, jack around with the exhaust, etc.. I'd focus on cheap and creative ways to cool the car.
Maybe you've already done that. If so, then you may have to move up to RX-8 injectors as the 99's run out of fuel around 180 RWHP. Sometimes people will run accessory injectors as there are some issues with the fueling on Miatas.
Corky Bell could be a huge resource if he was willing to pontificate for free.
You guys are an inspiration, keep up the outstanding work.
The way they flew by our 140hp pig, I'd say they are getting every bit of their indicated hp. Lowered, lightened, massive hp, engineers, dyno...I can do lowered, and lightened but the other stuff, not so much. There is no hope...I going out right now and shooting my pig.
That's assuming you're getting everything out of your 140HP pig. 
The way they flew by our 140hp pig, I'd say they are getting every bit of their indicated hp. Lowered, lightened, massive hp, engineers, dyno...I can do lowered, and lightened but the other stuff, not so much. There is no hope...I going out right now and shooting my pig.
We did dyno our pig at T'hill...140hp
Eyesoreracing.. You guys have dyno tests, but you're probably really not seeing what is going on with your car. Have you looked at on-track mid-race data? I wouldn't be suprised if your getting considerable heat soak, and are losing power after about the first 20mins.
Several dedicated Miata enthusiasts have spent countless hours trying to figure out cooling and reliability for turbo-d miata engines. Many guys have had issues with a drop in power with stock cooling in as little as 10-20 mins. So you may have picked up considerable HP on the dyno, you may not be getting that on the track.
Before you increase boost, or fuel, adjust timing further, jack around with the exhaust, etc.. I'd focus on cheap and creative ways to cool the car.
Maybe you've already done that. If so, then you may have to move up to RX-8 injectors as the 99's run out of fuel around 180 RWHP. Sometimes people will run accessory injectors as there are some issues with the fueling on Miatas.
Corky Bell could be a huge resource if he was willing to pontificate for free.
You guys are an inspiration, keep up the outstanding work.
We've been known to take on-track data:
We haven't done this since the big power bump, though. When we put the boost gauge on during testing in Florida, boost was creeping to 9 psi and the turbo was starting to glow, so we're definitely starting to drift out of the comfort zone. We're not entirely sure how to hold the boost down, since we already ported the wastegate as far as we can.
Oh, and creative cooling was handled up until the 2011 rules changes. Giant Mazda6 radiator in the passenger's seat, coolant reroute, no hood or front bumper. There's no heat soak with that setup. Putting a door across our radiator air intake and wrapping a hood around our turbo are not going to help cooling one bit.
-Dave
Have you considered throwing the turbo at the arse-end of the exhaust? Sure, you have a hella-long intake run, but it gets the heater out from under the hood.
Well, then I wold suggest you get some more on track data with new setup. You may find you reached a threshold where your actually losing ground by pushing forward. Sounds like you've definitely been thinking about the right things.
Water injection?
We haven't done this since the big power bump, though. When we put the boost gauge on during testing in Florida, boost was creeping to 9 psi and the turbo was starting to glow, so we're definitely starting to drift out of the comfort zone. We're not entirely sure how to hold the boost down, since we already ported the wastegate as far as we can.
Oh, and creative cooling was handled up until the 2011 rules changes. Giant Mazda6 radiator in the passenger's seat, coolant reroute, no hood or front bumper. There's no heat soak with that setup. Putting a door across our radiator air intake and wrapping a hood around our turbo are not going to help cooling one bit.
-Dave
You might have a cylinder by cylinder cooling issue. Engines with the water outlet near one end of the head can leave the far ends hotter and more prone to ping. Center is better but still leaves the outer cylinders a bit warmer. Playing with coolant flow stuff isnt exactly an easy thing to try or figure out.
Turbo in the rear means a separate turbo electric oil pump or the new oil le$$$$$ turbos. Not exactly Lemons budget friendly.
How about adding an external wastegate? Im sure you could pick up a deltagate or similar fairly cheap. With your turbo glowing and having boost control issues description im guessing your timing is getting to the low end of acceptable with pump gas and egts are getting pretty high.
Another option is stacking head gaskets to lower compression so you can turn timing back up which should cool the exhaust down and hopefully get boost under control.
Cooler plugs should help too if you didnt already. Also, slight misfiring can cause overboosting and a glowing turbo while in boost. Its not always obvious its misfiring in boost. Trying iridium plugs may help if the ignition is barely keeping up.
Maybe some of this you tried already, its just what i'd check/do/try.
We already did the coolant re-route thing. In the front, out the back now. Orginal Miata coolant path is in and out the front. Big problem.
Glowing turbo isn't really a concern, as exciting as it sounds. Go drive a factory turbo car with a 100,000 mile warranty in the dark and then open the hood. If you're driving like you mean it, the turbo will be glowing. I suspect the reason this was our first glow was because it was only the second night race, and the first one was freezing cold.
An external wasteagate is way out of the budget. We're basically at $500, so anything we do to the car at this point has to be offset by something. Notice how our new $50 had to be offset by selling off surplus engine parts and melting down scrap.
Easiest way to fix boost creep is just to shift 500 rpm sooner. We'll probably try that. And we'll probably fail, because revs are irresistable!
-D
Well, someone has to -
CHEATERS!!!!!!! OMG!!1!!1!!!!111
Actually, we might be running a similar drive setup this weekend. Our wastegate keeps us a a pretty solid 8 psi, so we might have some info.
Although we'll probably just blow up at 21 laps (pay up Judge Scott) and not have anything useful to share.
Build your own wastegate. I know you can. Use plumbing parts outta the company bathroom if you need to... And I want to see what it looks like so I can use it on the turbo-beetle.
I read the whole thing, awesome work, guys. The only two things I didn't like were the re-use of the main seals (you ever try getting one out intact? righttttt) and all the free stuff laying around the garage. Nothing is free. Anyway, great read and congrats on taking backyard engineering to F1 levels! We aspire to be a shadow of you guys...
We're not entirely sure how to hold the boost down, since we already ported the wastegate as far as we can.
That link was a great read, and I may have missed this, but where are you taking boost signal from? Right at the outlet from the compressor housing or post-IC or what? If you can get your signal really soon after the compressor housing, you will likely feed more signal to the wastegate actuator sooner in the rev range than you would if you take a signal from some point after the IC.
Another near-free idea might be to actually cut out holes around the wastegate (post flapper) and install a block-off inside the turbine housing to prevent reversion of the exhaust coming off the turbine wheel. So basically its a crappy internal gate made into a crappy external gate, with its own dedicated path separate from the main exhuast.
-Sparetire
My old Mazda 323 GTX couldn't stop creeping the wastegate either, which one of your's fault is that?
With an ultra-low restriction exhuast, sometimes its just easier for the exhaust to just going keep down the turbine rather than the hard 90deg into the wastegate port. There's a reason the Porsche 944 turbo exhaust is perfect, check the numbers behind that wastegate setup. Try adding some exhaust restriction on the turbine side if your flows are separated that much. I had an HKS catback (only decent complete aftermarket one) on my GTX and it made the creep even worse.
What does the bypass pathway looklike? It should have space to keep its velocity up because if it stalls as it gets through the wastegate flapper, its going to choke up the flow badly.
Also something has changed in the last few years since I've been in a forum about turbos, people are now calling early-open a creep, where it opens slowly as the boost pressure is realized, rather than over flowing at high rates. Whats up with that? All these kids spoiled by electronic boost control!
My old Mazda 323 GTX couldn't stop creeping the wastegate either, which one of your's fault is that?
With an ultra-low restriction exhuast, sometimes its just easier for the exhaust to just going keep down the turbine rather than the hard 90deg into the wastegate port. There's a reason the Porsche 944 turbo exhaust is perfect, check the numbers behind that wastegate setup. Try adding some exhaust restriction on the turbine side if your flows are separated that much. I had an HKS catback (only decent complete aftermarket one) on my GTX and it made the creep even worse.
What does the bypass pathway looklike? It should have space to keep its velocity up because if it stalls as it gets through the wastegate flapper, its going to choke up the flow badly.
Also something has changed in the last few years since I've been in a forum about turbos, people are now calling early-open a creep, where it opens slowly as the boost pressure is realized, rather than over flowing at high rates. Whats up with that? All these kids spoiled by electronic boost control!
This is probably spot on - the Capri never had any boost issues this weekend - went to 8 psi and stayed there like a rock, because we still have the factory exhaust, minus the fancy metal ceramic whatever that normally resides inside the cat.
We were shifting at around 5500 - 6000 though, but even the few times I went above our agreed upon shift point due to racing or whatever, I never saw the boost gauge go up.
So - more restrictive exhaust = less boost creep. They design these things at the factory that way for a reason, I guess.
great article!!!!!!!!!!!!!!!!!!
No wonder the miata was so fast at Sears.....I always thought you guys were around 145whp....... 192whp explains a fair amount of speed!!!!
Still its not the power of the Miata that is its strength...its RELIABLE and handles very well...
So here is a ??? for you....what kind of racing gas mileage do you get at 192whp? The 200whp 928 hovers between 7-10 gallons per HOUR....but is blessed with a 23 gallon stock tank too....I would think the turbo is worse (BSFC anyway) but 700 less lbs has to help too....
The 24 Hours of Lemons Forums → Lemons Tech → Eyesore Racing dyno charts