MX 5 The current Project

how come you've went for such huge injectors then?

Sounds good, 230bhp is well enough for a '5, but i cant help but feel dissapointed that you arent going 450bhp+, lol

good to hear from you Martin glad to see you still playing the the MX5

did you get the clutch sorted??

thanks

Jason

Hi Jason

Still playing just the job means I can't do as much as i would like

clutch is still holding in there just and am just driving around it right now, I'm having trouble getting the uprated one I want and have been let down 3 times now.

Mini update

Megasquirt sat on the table ready to go on, AEM wideband should be here tomorrow.
so all that is left to do now is

1 Remove supercharger
2 Fit new heat blanket to manifold
3 Remove lambda
4 Fit wideband
5 Re-fit supercharger
6 Wire up wideband controller
7 Remove piggyback Fuel controller
8 Remove O2 clamp
9 Plug in Megasquirt
10 Fit GM intake temp sensor
11 Change J&S Settings
12 Tune!!!!

piece of cake

going to start with the 320 injectors for now and swap to the bigger ones once I get the hang of Megasquirt tuning

so its a simple 5 min job then lol

nice to hear its going well with the old mx5, cant wait to see this in action some day

Ye it sounds so easy lol im lookin forward to the finished product

Megasquirt fitted and tuning has begun in earnest

Many thanks to Jason for his help swapping the lambda sensor!

Looking reak good mate, simply fell in love with the idea of sitting at home on the drive mapping my own car through the laptop haha youve got me thinking

Looking forward to the results mate

Thanks

VE Analyse Live is pure witchcraft the more you drive the faster you go!!

Run out of injectors though now, I managed to hit 88.9% duty cycle at no where near full boost or RPM

need to sort out idle and cold start as well but not putting any effort into that until I get even bigger injectors

Anyone with a 230bhp RX8 that fancies donating their injectors to the cause

new Injectors should be here tomorrow with any luck so can get on with tuning again

As the MS is map based fuelling I've now been able to remove the recirc dump valve with a vent to air one, I just need to find a bit of pipe to replace the MAF now and I can get rid of it completely

Gets better and better cant wait to hear it venting to air

Jason

The DV needs adjustment poor thing sounds like a sneeze at the minute and is leaking at the transition to boost

New injectors here though now and fitted (what a B'stard they were to fit)

Duty cycles down better now but more tuning is still needed


but the bloody thing is getting faster and faster

would love to see this in action sometime

New bigger injectors still not big enough

swapped in some 530cc RX8 injectors today duty cycles much better and hitting AFR targets now easily also they are able to keep up with acceleration enrichment that the others were struggling with

Dump valve now adjusted so it doesn't sound like it has a cold

still lots of tuning to do though starting is a PIA and cold idle is rough but hot idle is lovely now though.

remarkably the car is actually more economical than before a couple of motorway runs over to my office in Liverpool returned 38MPG!!

Tuning coming on great, now hitting the AFR targets and cold start problem now sorted.

going on the rollers in a couple of weeks just to confirm that everything is right and providing the clutch holds up I might even get a power figures.

I'm hoping for over 200 bhp on the first try considering the timing map still needs work, if not I may need to call in Jason and his amazing cable ties


Also there is a mega RR day Sheffield way on the 15th for MX5's that will feature cars that make mine look stock (but I'll be there) if anyone fancies some RWD spectator sport?

nice, so come on pray tell, whats the magic number??

Not enough yet

I really just put it on so I could get some data logs

it has a very very conservative ignition map so the 180bhp was no surprise. there is loads more tuning still to be done.

What kind of power are you shooting for?

what are they stock?? and i am sure you will get it to be a really drivable and quick car after what jaytold me about your old cinq turby lol

They are 140bhp and 120lbft stock so 180 and 170lbft is a good improvement but I reckon there is at least 30 or 40 more bhp to find yet. Just need to spend some more time tuning but as I'm learning the MS as i go along it may take a little while

Think I may have found the problem
after yesterdays RR I found my car was making less power with the megasquirt fitted than before with a powercard. I just put it down to the fact that as it is all new to me I hadn't tuned the car very well. So knowing the spark map is important for power last night I looked at countless examples on all the various MX5 sites and even though my map is slightly conservative it is not a million miles away so thought it is time to read some more.

However I had an epiphany at 2 o'clock this morning, I still have a J&S Ultra fitted to my car as my MS doesn't have knock control and one of the features of the Ultra safeguard is that it can retard the ignition on boost. I used this before the MS was fitted to keep the car safe and was pulling 1.5degrees per one PSI above 5PSI. Now I did change some settings when i fitted the MS but all i in fact altered was the boost start point to zero and left the rate unchanged.

Now what this means is that it was actually starting to pull 1.5 degrees per PSI as soon as it hit boost so at full boost it was pulling around 14 degrees on top of what the slightly conservative map on the MS was doing so the car was even more retarded that what I've been

So I've twiddled the right knobs on the J&S this morning and the car is a totally different beast,

Back on the rollers today

First Run 230 BHP and 210lbft

oh wow thats errrmmmmmm rather alot it a lightwieght 2 seater lol, hmmm i bet its, how can i put this cleanly, better when wet?

Err I know, was actually getting wheel spin on the rolling road

Have backed the timing off a bit for now so now backed off to around 210 bhp and 190lbft for the winter

need to save pennies now for an even more uprated clutch than I was planning.

But I've managed to find an even smaller charger nose pulley so a bit more boost still to come....roll on spring