Small MX-5 mods
- Thread starter DRZ
- Start date
RX8 injectors fitted!
It started and (just about) ran without any adjustment to the AEM whatsoever, but I made a few changes to remove some fuel and it now drives "fine". Tip-in enrichment is so rich the engine cannot cope with the fuel and my wideband goes off the low end of the scale... Other than that, it seems fine. AFR of 12 at WOT in every gear, idle was a bit rich so I pulled some fuel and it is now idling between 14.5 and 15.3 ish (bats up and down between the two). I'd not actually hooked the sensor up before I put the injectors in (did them both today) so I have no idea what stock looks like...
ops:
Tomorrow I'll be building up the SC with its manifolds and making sure it all fits as I expected. I know I need to grind a little bit more off the casting to get the outlet pipe on and I will have to shave some of the inlet off to get the pipework over but other than that it should be relatively plain sailing. Brackets should have been here this weekend but they didn't show up so I can't get the charger on the car so that'll have to wait for next weekend.
It started and (just about) ran without any adjustment to the AEM whatsoever, but I made a few changes to remove some fuel and it now drives "fine". Tip-in enrichment is so rich the engine cannot cope with the fuel and my wideband goes off the low end of the scale... Other than that, it seems fine. AFR of 12 at WOT in every gear, idle was a bit rich so I pulled some fuel and it is now idling between 14.5 and 15.3 ish (bats up and down between the two). I'd not actually hooked the sensor up before I put the injectors in (did them both today) so I have no idea what stock looks like...
ops:Tomorrow I'll be building up the SC with its manifolds and making sure it all fits as I expected. I know I need to grind a little bit more off the casting to get the outlet pipe on and I will have to shave some of the inlet off to get the pipework over but other than that it should be relatively plain sailing. Brackets should have been here this weekend but they didn't show up so I can't get the charger on the car so that'll have to wait for next weekend.
Yesterday evening I was feeling pretty despondent about this:
After thinking through a number of doomsday scenarios I decided that the numbers just didn't make any sense, so it MUST have been a firmware issue. Did some digging and found out that there are indeed differing firmware levels and some cars prefer one over the other. USB cable + 15 minutes later:
Now I know that the AEM knows for sure what is going on, I can proceed with a bit more belief that I'm going to be able to get a basic map running properly.
After thinking through a number of doomsday scenarios I decided that the numbers just didn't make any sense, so it MUST have been a firmware issue. Did some digging and found out that there are indeed differing firmware levels and some cars prefer one over the other. USB cable + 15 minutes later:
Now I know that the AEM knows for sure what is going on, I can proceed with a bit more belief that I'm going to be able to get a basic map running properly.
Associate
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- 28 Feb 2007
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Looks like you have got a nice stable idle now, I presume your throttle reading is MAP based? Are you using this for your acceleration enrichment? - Just that it looks quite noisy (unless thats your idle valve??)
I take the reading from TPS and that is my idle valve (plus a couple of blips!). I do have a MAP sensor plumbed in too though, that is the only real way of measuring load properly.
EDIT: Worth pointing out that my idle didn't change, just what the AEM was seeing. The idle was always as the 2nd graph shows
EDIT: Worth pointing out that my idle didn't change, just what the AEM was seeing. The idle was always as the 2nd graph shows
Caporegime
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Only on the phone so no proper reply, but it's all looking good, niceone!
Bar a belt and some appropriately sized bolts, I am now finally in possession of everything I think I need for tomorrow's fitting. I'm praying that I get a decent crack at it despite the weather.
My only point of concern is connecting up the bypass valve. It is very tight and with the pipework I have I might struggle. I'm also hoping that my guesstimated inlet pipework is going to squeeze around the ABS pump. I should be OK but the pipework has cost me a bomb so I'll be annoyed if I've messed that up!
I've driven the car N/A a few times now with the RX-8 injectors in and bar cold starting, it feels fairly OEM after a bit more fiddling so I should be in with a chance of getting the fuelling alright for the RR. One little job I need to do is to get the WB O2 sensor connected to the AEM FIC so that I can log it with the rest of the data.
My only point of concern is connecting up the bypass valve. It is very tight and with the pipework I have I might struggle. I'm also hoping that my guesstimated inlet pipework is going to squeeze around the ABS pump. I should be OK but the pipework has cost me a bomb so I'll be annoyed if I've messed that up!
I've driven the car N/A a few times now with the RX-8 injectors in and bar cold starting, it feels fairly OEM after a bit more fiddling so I should be in with a chance of getting the fuelling alright for the RR. One little job I need to do is to get the WB O2 sensor connected to the AEM FIC so that I can log it with the rest of the data.
Man of Honour
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Mine always ran a little rich on idle, but on full boost was bang on stoich. Had idle issues initially where it would just go lumpy and die for exactly the same reasons.
Looks like you're getting on nicely!
Looks like you're getting on nicely!
Once you're done we should swap keys and compare
I don't have a problem with that
In a way it is a shame it'll be done just in time for the bleak winter but it should be fairly sweet having the whole of next spring/summer with it 'charged
If I manage to get it driving this weekend I'll be running it at the RR day on the 17th, weather permitting.
Mine always ran a little rich on idle, but on full boost was bang on stoich. Had idle issues initially where it would just go lumpy and die for exactly the same reasons.
Looks like you're getting on nicely!
Are you sure those weren't the other way round. Bang on stoich at full boost and load is a recipe for it to just go bang. Should be around high 11s to low 12s to provide some nice in cylinder cooling.
Man of Honour
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yes Minor update:
Started the weekend with the engine bay looking like this:
Took the standard airbox and filter off and fitted the TR Lane tensioner and test-fitted the SC bracket:
Bodged on the MAF so I could move the car
Tight with some of the cables and the mini filter!
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IMPORTANT NOTE!
You CANNOT do what I did here and go through the back of the tensioner adjustment slider as I found out later after trying to fit the mounting bar, which touches the back of the slider (it is VERY tight in there!) It is threaded so that you don't need to do this. I cut down that bolt and went in from the front and used a washer to make sure that there was zero protrusion and even then there wasn't enough clearance. I had to thin down the TR Lane support bar (as well as opening up the hole as they come pre-drilled at least 5mm out... oh and I had to grind some off the end so that it would clear the cam belt cover...)
Other than that, this bit is plain sailing.
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I spent most of Saturday morning recovering from what ended up being a very late night on Friday, and most of today recovering from working through Saturday despite being shattered and still going out Saturday night. A load of setbacks in various guises meant a lot of Saturday was wasted. Incorrect sized bolts, inappropriate pipework and far more modifying of the TR Lane stuff than I am really happy with formed the most of that. Finding a belt involved a stroke of luck finding perhaps the only Motor Factors in the entire universe open on a Sunday that actually stocks good/useful stuff. I picked up two Gates 5pk 1255 belts for the princely sum of £32 and cut a rib off.
By the end of the above, I was thoroughly ****** off with the entire thing.
Pressed on though...
Cut down the other side of the throttle body so that it wouldn't foul on the exhaust manifold:
...and then fitted the SC!:
I had to bodge an inlet tract though as the pipework I have doesn't fit around the heater pipes at the back. I have a plan to deal with this, but here it is for now:
Not pretty, but it will do for now.
Took it for a drive around the block and my conservative map works just about (very very rich everywhere) but so conservative that if I use WOT or go above about 2500rpm it goes even richer and dies! I'll have to take out some fuel, add in a bit more timing and see how I get on. I get the whine though, oh yes
Started the weekend with the engine bay looking like this:
Took the standard airbox and filter off and fitted the TR Lane tensioner and test-fitted the SC bracket:
Bodged on the MAF so I could move the car
Tight with some of the cables and the mini filter!
-----------------------------------------------------------------------------------------------------------
IMPORTANT NOTE!
You CANNOT do what I did here and go through the back of the tensioner adjustment slider as I found out later after trying to fit the mounting bar, which touches the back of the slider (it is VERY tight in there!) It is threaded so that you don't need to do this. I cut down that bolt and went in from the front and used a washer to make sure that there was zero protrusion and even then there wasn't enough clearance. I had to thin down the TR Lane support bar (as well as opening up the hole as they come pre-drilled at least 5mm out... oh and I had to grind some off the end so that it would clear the cam belt cover...)
Other than that, this bit is plain sailing.
-----------------------------------------------------------------------------------------------------------
I spent most of Saturday morning recovering from what ended up being a very late night on Friday, and most of today recovering from working through Saturday despite being shattered and still going out Saturday night. A load of setbacks in various guises meant a lot of Saturday was wasted. Incorrect sized bolts, inappropriate pipework and far more modifying of the TR Lane stuff than I am really happy with formed the most of that. Finding a belt involved a stroke of luck finding perhaps the only Motor Factors in the entire universe open on a Sunday that actually stocks good/useful stuff. I picked up two Gates 5pk 1255 belts for the princely sum of £32 and cut a rib off.
By the end of the above, I was thoroughly ****** off with the entire thing.
Pressed on though...
Cut down the other side of the throttle body so that it wouldn't foul on the exhaust manifold:
...and then fitted the SC!:
I had to bodge an inlet tract though as the pipework I have doesn't fit around the heater pipes at the back. I have a plan to deal with this, but here it is for now:
Not pretty, but it will do for now.
Took it for a drive around the block and my conservative map works just about (very very rich everywhere) but so conservative that if I use WOT or go above about 2500rpm it goes even richer and dies! I'll have to take out some fuel, add in a bit more timing and see how I get on. I get the whine though, oh yes
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I managed to move my car with no air flow metering before, when my inlet pipe detached itself down a country lane. Just takes a bit of quick feet on the throttle
Re the whine, do you have a bypass valve so the charger isn't, er, charging at part throttle?
I managed to move my car with no air flow metering before, when my inlet pipe detached itself down a country lane. Just takes a bit of quick feet on the throttle
Re the whine, do you have a bypass valve so the charger isn't, er, charging at part throttle?
I do, I have a bypass valve from the MINI Cooper S - so perfect for the 'charger. On the MINI the bypass valve is actuated by the vacuum between the supercharger and the second throttle body but on the MX-5 this isn't quite strong enough so I've run some vac hose to the inlet manifold which has more than enough vac to drive the valve.
When I go to a bigger pulley the bypass valve won't open quick enough so I will have to fit a recirculating dump valve else I'll end up stalling the charger.
Man of Honour
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looking damn good I think by the time mine comes out of warranty the bbr cosworth kit will be tried and tested enough for me to give it a go... shame its so expensive relatively!
I think by the time mine comes out of warranty the bbr cosworth kit will be tried and tested enough for me to give it a go... shame its so expensive relatively!
Caporegime
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- 11 Mar 2005
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- Leafy Cheshire
Good work, it's always best to overfuel at first but i'd pull as much back as possible, whilst it's good not to get any det too much fuel can cause bore wash so i wouldn't run it like this for too long.
On another note SC noise is so addictive, if it was anything like mine it sounds epic in the cabin.
On another note SC noise is so addictive, if it was anything like mine it sounds epic in the cabin.