OMX-596 - 1996 Spec'd NA6 - Updated 21 Apr 2013

[orx626]

by fractions you mean at least a couple

....eventually

[Saffa]

Can't wait to see what figures you get there on Friday Danny. My car goes up to TAS this Saturday for a week to get my supercharger kit on and get tuned. (Though I think BEGi may have stuffed up my order of their coolant reroute so I may have to wait and see about that )

Anyway mate, enjoy the drive home on Friday afternoon

[orx626]

Well, what an exciting day!!!

At 6am this morning Mokesta and myself made the 135km trek up to TAS Performance Automotive in Toowoomba to have our Megasquirt PNP's dyno tuned. "Why 135km away? Isn't there anyone closer I hear you ask?" Not to our knowledge, and we had already received positive first-hand feedback from other MX5 owners who had used TAS's Megasquirt dyno tuning expertise.

Now before I get into what the numbers were, I'll give you the performance summary from "the seat of my pants dyno"! In two words "SIMPLY OUTSTANDING". The torque available from under 2,000 rpm through to 6,500 rpm is simply astounding . The thing is just soooo driveable...2,000rpm in 6th gear, accelerator pedal to the floor, no stutter, just plain grunt...as if it were an engine of a much larger capacity. Inclines are just soooo effortless now! Just what I was hoping for .

Getting back to the numbers side of things...there were a couple of surprises. I won't go into Mokesta's day...I'll let him do that at his leisure in his own thread http://mx5cartalk.com/phpBB-3.0.2/viewtopic.php?f=57&t=31457&start=30.

As mentioned, from what I had read and heard, I expected my s'charger/pulley combination to generate a peak boost pressure of around 7 psi. In reality it was a little bit less, at a tad under 6 psi. Some time was then spent making sure that there were no leaks and that the by-pass valve was closing fully. Everything was found to be in order. That was the first surprise, the second was the change that TAS had made to their dyno tuning setup. The dyno is a Dyno Dynamics two-wheel drive unit that has a correction factor in the software to adjust the measured hp to a value as if it were being dynoed at sea level. The reason why this is significant is that Toowoomba is around 700m above sea level and the air density is less than that at sea level. Now, up until recently all their hp curves were adjusted according to this correction factor, but what TAS had found was that it was over-inflating the sea level hp and have consequently turned this function off. It has no effect on how the tuning work is performed, it is just to give us numbers on a bit of paper for pissing competitions .

The reason I have stated the above is that Big G had is M45 boosted NA6 tuned by them last year and produced a whp figure of 145. Which as you can see when compared to the below graph, is 10 hp more. So I had to ask TAS what they thought Big G's car would have turned the rollers at if it were here with us today. They estimated around 20hp less at 125 hp . No wonder they decided to drop the correction factor!!! Me thinks customers may have had there cars on dyno's closer to sea level and found they didn't have the power they thought they had . With that being the case, then all seems as it should be with my s'charger install. If I really want a semi-valid comparison I need to put the car on the dyno I did a power run before any of the engine modifications were done...I may do this sometime to get a feel for the % increase in engine performance.



How good is that power curve...it's almost a straight line from 2,500 rpm through to 6,250 rpm The torque curve is flat as!!! The air/fuel ratio is spot on as well...thanks TAS.

Here is the boost curve. Ignore the Customer Name, they hadn't changed over the owner/vehicle details from Mokesta's to mine . As you can see the boost curve fluctuates between 4 and 6 psi as the air flow dynamics of the engine and supercharger change through their respective rev ranges. 4 psi @ 2,500 rpm!!!! I will have to hook up a temporary boost gauge to see what boost is available just off idle.



Time to book in for the March 5th trackday. That's it for the moment on this beasty...time to get back onto the NC.

Cheers,
Danny

[orx626]

Can't wait to see what figures you get there on Friday Danny. My car goes up to TAS this Saturday for a week to get my supercharger kit on and get tuned. (Though I think BEGi may have stuffed up my order of their coolant reroute so I may have to wait and see about that )

Anyway mate, enjoy the drive home on Friday afternoon

It was certainly a fun drive home Gregg....old hard tyres, bucket loads of torque and copious amounts of water on the road made for plenty of excitement!!!

Your car is in good hands...looking forward to seeing what the M62 does for your performance.

Cheers,
Danny

[Jace]

such a spot on power curve! nice work by you, as well as the TAS guys. the car is about as good as it gets engine wise for an MX5 as far as i'm concerned.
great stuff.

[93_Clubman]

Sounds & looks great Danny. I too thought you'd have seen 7 psi, or just under, but as you would have read the stock JRSC kit (larger SC nose pulley & no upgraded belt tensioner) was sometimes quoted at 4.5 - 5.0 psi, which I guess also accounts for the hp#. Still your enjoyment of the on the road result is what counts, & it sounds very impressive. Congrats!

[timk]

Looks very nice Danny! To save you the hassle of hooking up a boost guage, we can just hook up a laptop and datalog it for a bit to see what boost you make at/near idle.

How's the idle control holding up with both the blower and air conditioning?

[orx626]

Looks very nice Danny! To save you the hassle of hooking up a boost guage, we can just hook up a laptop and datalog it for a bit to see what boost you make at/near idle.

How's the idle control holding up with both the blower and air conditioning?

Hi Tim, the idle control needs some further fine tuning with regards to compensating for the air-con load at idle. Will get to it as soon as I get a chance.

Regards,
Danny

[Saffa]

Looks very nice Danny! To save you the hassle of hooking up a boost guage, we can just hook up a laptop and datalog it for a bit to see what boost you make at/near idle.

How's the idle control holding up with both the blower and air conditioning?

Hi Tim, the idle control needs some further fine tuning with regards to compensating for the air-con load at idle. Will get to it as soon as I get a chance.

Regards,
Danny

I dropped my car off at TAS this morning and Matt said that you would be having a look at getting the idle valve and aircon tuned to run a bit better, in my case the aircon crapped out about a month ago and wont be getting fixed till just before next summer, but i'd be interested to see how you go with it all.

My idle valve was making some funky sounds before, but Matt says they learnt a few things when dealing with your Megasquirt yesterday that should at least reduce its noise.

[graemebc]

Awesome stuff btw how much is their service per hour? I will be taking mine up when I get back from Melbourne

[orx626]

Awesome stuff btw how much is their service per hour? I will be taking mine up when I get back from Melbourne

Hi Graeme, they didn't break the dyno tune down into an hourly rate. The total amount was $450 and it took around 3 hours. So you could say that their hourly rate for dyno tuning is $150.

Cheers,
Danny

ps. I got your PM....no problem, will see you when you return from Melbourne.

[timk]

Hey Danny,

I'll try to not derail this thread too badly but you may want to look into the dashpot RPM target adder stuff too. I had stalling problems when coming to a stop after putting the clutch in with the air conditioning running, turns out I had to trigger a tashpot event to cure this. As I said on the phone I'm really rusty with this stuff now, but here's what my dashpot settings were on my JRSC M45 equipped NA with a BMW TPS:



This would cause the MSPNP to have a closed loop RPM target of 1300 (900+400) for 2.5 seconds after the dashpot TPS event occurred, eliminating most of the stalls.

Hope this helps!

Cheers

[orx626]

Hey Danny,

I'll try to not derail this thread too badly but you may want to look into the dashpot RPM target adder stuff too. I had stalling problems when coming to a stop after putting the clutch in with the air conditioning running, turns out I had to trigger a tashpot event to cure this. As I said on the phone I'm really rusty with this stuff now, but here's what my dashpot settings were on my JRSC M45 equipped NA with a BMW TPS:

This would cause the MSPNP to have a closed loop RPM target of 1300 (900+400) for 2.5 seconds after the dashpot TPS event occurred, eliminating most of the stalls.

Hope this helps!

Cheers

Thanks for taking the time Tim . I will hopefully get a chance to have a play with the settings today.

Regards,
Danny

[Mokesta]

Danny, have you still got that G-tech (or similar) meter? How about we find a quite stretch of road and work out some performance times?

M

[Big G]

Hi Guys
Looks like a real good day over at Toowoomba!!
Re the figs on HP, it looks like I'm getting about 9-10 less than you Danny, I guess this is less boost [75 ish mm nose pulley and 1.6 versus 1.8 engine] Maybe I'll get a smaller nose pulley. Whatever the figures the change in driveability is amazing, well worth the time and money IMHO

Geoff