Soldato
- Joined
- 11 Dec 2005
- Posts
- 11,363
- Location
- Cheshire
Looking good mate, love seeing progress like this.
Small MX-5 mods
- Thread starter DRZ
- Start date
Been out to do some runs tonight. Saw 5.2PSI of boost at around 4,000rpm. Need some det cans but I was pouring in quite a lot of fuel and it was running alright but significantly better at part throttle where my AFRs were back on the scale.
The difference was understanding exactly how to set the stock O2 narrowband sensor maps, which I had a bit of a eureka moment on about midway through the evening but also realising that I had a setting slightly out on the setup page which meant the AEM didn't have enough poke to take control of the O2 sensor signal properly. As soon as I had cracked that I was back in control of my fuelling, which was a real breakthrough moment.
I've taken a fair bit of fuel out of the map now I've convinced my MacBook to charge (piece of crap needs to be replaced with a Pro tbh!)
1 degree ish of timing retard per PSI of boost should be pretty safe with the extra fuel levels I'm running and some V-Power in the tank. I think if these new maps look/feel OK on the car tomorrow I'm at a stage where I should be happy to drive the car around a bit more normally knowing that I'm not going to kill my sensors and the cat with all the extra fuel.
The difference was understanding exactly how to set the stock O2 narrowband sensor maps, which I had a bit of a eureka moment on about midway through the evening but also realising that I had a setting slightly out on the setup page which meant the AEM didn't have enough poke to take control of the O2 sensor signal properly. As soon as I had cracked that I was back in control of my fuelling, which was a real breakthrough moment.
I've taken a fair bit of fuel out of the map now I've convinced my MacBook to charge (piece of crap needs to be replaced with a Pro tbh!)
1 degree ish of timing retard per PSI of boost should be pretty safe with the extra fuel levels I'm running and some V-Power in the tank. I think if these new maps look/feel OK on the car tomorrow I'm at a stage where I should be happy to drive the car around a bit more normally knowing that I'm not going to kill my sensors and the cat with all the extra fuel.
Took out a lot of fuel, now back on the AFR scale. Still pretty rich but also making what feels like epic power right through to 4-5k rpm.
Blew a boost pipe off at full boost. Holy christ that's a very loud and very scary moment!
Blew a boost pipe off at full boost. Holy christ that's a very loud and very scary moment!
Dual Throttle Body setup: COMPLETE!
What a pain in the arse that turned out to be! I'd ordered a throttle cable from a Mk2 1.6 and it was only about 80cm long! Not wanting to make the same mistake again I ordered a throttle cable repair kit, cut the 1.6 inner cable and threaded the repair kit cable through the outer. I've had to ghetto up some brackets which really aren't that pretty a solution at all but for an 11th hour heath robinson lashup it works pretty well.
O...M...G at how heavy the throttle cable now is though! I need to adjust the spring tension by quite a lot so I don't end up with a right leg like hercules.
That aside, it really does make an amazing amount of difference to how the car drives and it validates the mapping work I did last night as the car absolutely flies in the mapped ranges (not so much in the parts of the range that are still too rich though...).
Gave it one WOT run in 3rd on the way home and it sounds really really really REALLY FREAKING AWESOME
What a pain in the arse that turned out to be! I'd ordered a throttle cable from a Mk2 1.6 and it was only about 80cm long! Not wanting to make the same mistake again I ordered a throttle cable repair kit, cut the 1.6 inner cable and threaded the repair kit cable through the outer. I've had to ghetto up some brackets which really aren't that pretty a solution at all but for an 11th hour heath robinson lashup it works pretty well.
O...M...G at how heavy the throttle cable now is though! I need to adjust the spring tension by quite a lot so I don't end up with a right leg like hercules.
That aside, it really does make an amazing amount of difference to how the car drives and it validates the mapping work I did last night as the car absolutely flies in the mapped ranges (not so much in the parts of the range that are still too rich though...).
Gave it one WOT run in 3rd on the way home and it sounds really really really REALLY FREAKING AWESOME
It is a hell of a feeling, and I've only done a minor amount of stuff compared to, say, a kit car or that Warner R4 project!
I've always loved working on cars and so doing this - overcoming all of the little hurdles here and there etc makes me really think that at some distant point in the future I'd have the confidence to build a kit car up.
Soldato
- Joined
- 2 Mar 2004
- Posts
- 11,918
- Location
- SE England
Always a good rule of thumb, that, when tuning a forced induction car. Go rich, and all you'll do is continually foul plugs and maybe wash fuel down the bores. Set things up too lean and, well, you'll only do that once
So, late last night I finished making my intake pipework fit, changed to colder plugs and generally made sure everything was safe. Went to bed at 1am after tweaking the mapping a little bit (sat at my desk!).
Loaded the map onto the ECU this morning and drove down to Powerstation. To say I was nervous would be a bit of an understatement!
http://www.static-hiss.co.uk/mx5/scbuild/182bhprrgraph.jpg
Result: 182.2bhp corrected for the air temp (184.3bhp 'raw') @ 7440rpm. 138lbf.ft torque at 5575rpm.
Pretty pleased with that all things considered
Loaded the map onto the ECU this morning and drove down to Powerstation. To say I was nervous would be a bit of an understatement!
http://www.static-hiss.co.uk/mx5/scbuild/182bhprrgraph.jpg
Result: 182.2bhp corrected for the air temp (184.3bhp 'raw') @ 7440rpm. 138lbf.ft torque at 5575rpm.
Pretty pleased with that all things considered
Soldato
- Joined
- 2 Mar 2004
- Posts
- 11,918
- Location
- SE England
I don't know much about the specific limitations of these but I'd be inclined to keep the RPMs below 7000RPM - more than that just looks like a recipe for putting a rod through the block, or wrecking a piston.
People run 150bhp more than I am doing, regularly track them and only when really really pushing the edge of the envelope do they have issues. mk1_salami on here is running 321bhp and he is on the ragged edge and blew his engine but with a good tune at 200bhp I'm not in massive danger...
There aren't really any limitations, the little engines are solid as anything. Mine makes peak power at 7.2k and has done for two years with no issues whatsoever. They just smile and beg for more, seriously.
This!
Internals are rated to 250bhp before you need better stuff. The engine was designed to be turbocharged originally so there is a LOT of headroom to play with
Those of you at the RR will have seen the deterioration of my temporary bypass pipe first hand. Basically, the pressure in there was quite a lot higher than I anticipated and it just blew the pipe apart.
Replaced it with the pipework I ran out of time to make fit:
Went for a drive and it seems all good. First time I've gone through the gears WOT properly from 2nd. Seriously seriously impressed with how quickly it picks up speed. Ridiculously impressive the difference it has made - and thats at 182bhp! When I get to the 200 mark it is going to feel incredible.
Stopped dicking around and took some photos:
The Mk2.5 centre console I fitted and forgot to picture:
Interior generally:
So, all in all I'm quite pleased but that isn't the end of the story!
This arrived:
A Japspeed 52mm Alloy radiator.
Thick!
vs the stock rad:
Probably do that in the new year now though, running out of weekends in 2011!
Replaced it with the pipework I ran out of time to make fit:
Went for a drive and it seems all good. First time I've gone through the gears WOT properly from 2nd. Seriously seriously impressed with how quickly it picks up speed. Ridiculously impressive the difference it has made - and thats at 182bhp! When I get to the 200 mark it is going to feel incredible.
Stopped dicking around and took some photos:
The Mk2.5 centre console I fitted and forgot to picture:
Interior generally:
So, all in all I'm quite pleased but that isn't the end of the story!
This arrived:
A Japspeed 52mm Alloy radiator.
Thick!
vs the stock rad:
Probably do that in the new year now though, running out of weekends in 2011!
Soldato
- Joined
- 11 Dec 2005
- Posts
- 11,363
- Location
- Cheshire
Seriously sounded impressive yesterday. I think I win the award for the smallest supercharger lol