Megasquirt kits for a 4.0 Chim - What to choose?
Discussion
Hi all.
I've recently acquired a 4.0 Chimaera and would like to fit megasquirt for a few reasons.
1. To lose the distributor with old style coil and have better control over fuelling/ignition - essentially remove points of failure and release a few HP.
2. To have two maps (one for Performace and an "Eco" map for MOT time.
3. In the future to support the addition of a supercharger kit.
My question is which kit to go for for the TVR and what else would I need?
ExtraEFI seem to have a few options, I was considering the MS2X kit as this seems to cover my needs of changeable maps and fan control etc, there aslo appear to be kits from Megasquirt-V8.co.uk
To simplify things, ensure reliability and neaten the install I would like to have a pre-made wiring harness, it looks like this can also be ordered from ExtraEFI for £230 or can be bought from Shaun at MS2Tuning, Any suggestions on which one to go for?
What about injectors, I understand the Lucus injectors are pretty old tech now and newer pintle types are better. I was looking at something like Bosch 0280150947 as fitted to the Mustang, From what I've read they should be sufficient for over 320hp when I get around to fitting a Superchanger.
Specs are:
Flow rates @ 43.5 psi / 3 bar
24 lb per hour
187.5 G per min. (N-Heptane)
260 cc per min
14.3 Ohm resistance
Or are there better injectors I should use?
Any advice on what you chose or what you would have done differently would be greatly appreciated.
I've recently acquired a 4.0 Chimaera and would like to fit megasquirt for a few reasons.
1. To lose the distributor with old style coil and have better control over fuelling/ignition - essentially remove points of failure and release a few HP.
2. To have two maps (one for Performace and an "Eco" map for MOT time.
3. In the future to support the addition of a supercharger kit.
My question is which kit to go for for the TVR and what else would I need?
ExtraEFI seem to have a few options, I was considering the MS2X kit as this seems to cover my needs of changeable maps and fan control etc, there aslo appear to be kits from Megasquirt-V8.co.uk
To simplify things, ensure reliability and neaten the install I would like to have a pre-made wiring harness, it looks like this can also be ordered from ExtraEFI for £230 or can be bought from Shaun at MS2Tuning, Any suggestions on which one to go for?
What about injectors, I understand the Lucus injectors are pretty old tech now and newer pintle types are better. I was looking at something like Bosch 0280150947 as fitted to the Mustang, From what I've read they should be sufficient for over 320hp when I get around to fitting a Superchanger.
Specs are:
Flow rates @ 43.5 psi / 3 bar
24 lb per hour
187.5 G per min. (N-Heptane)
260 cc per min
14.3 Ohm resistance
Or are there better injectors I should use?
Any advice on what you chose or what you would have done differently would be greatly appreciated.
Decide who's going to map it and take their advice.
FWIW I think your idea of separate maps for economy and performance is pointless. Why would you have a map that was not optimised for both?
I'm sure you could get almost any model working. I went for MS1/Extra because it gave me better features and support for more injectors but if you're using a conventional manifold and cam you won't need any of that. If you can crimp a connector I wouldn't consider it important to reuse the old harness and replacing it will get rid of a lot of decades old wiring and connectors. You'll need to wire in the additional sensors in any case.
FWIW I think your idea of separate maps for economy and performance is pointless. Why would you have a map that was not optimised for both?
I'm sure you could get almost any model working. I went for MS1/Extra because it gave me better features and support for more injectors but if you're using a conventional manifold and cam you won't need any of that. If you can crimp a connector I wouldn't consider it important to reuse the old harness and replacing it will get rid of a lot of decades old wiring and connectors. You'll need to wire in the additional sensors in any case.
GreenV8S said:
Decide who's going to map it and take their advice.
FWIW I think your idea of separate maps for economy and performance is pointless. Why would you have a map that was not optimised for both?
I'm sure you could get almost any model working. I went for MS1/Extra because it gave me better features and support for more injectors but if you're using a conventional manifold and cam you won't need any of that. If you can crimp a connector I wouldn't consider it important to reuse the old harness and replacing it will get rid of a lot of decades old wiring and connectors. You'll need to wire in the additional sensors in any case.
Thanks for your reply, some good points.FWIW I think your idea of separate maps for economy and performance is pointless. Why would you have a map that was not optimised for both?
I'm sure you could get almost any model working. I went for MS1/Extra because it gave me better features and support for more injectors but if you're using a conventional manifold and cam you won't need any of that. If you can crimp a connector I wouldn't consider it important to reuse the old harness and replacing it will get rid of a lot of decades old wiring and connectors. You'll need to wire in the additional sensors in any case.
My reasoning behind having the two maps was not to have two maps to drive on but basically to try and do a VW and have a map that would be literally only used to run ultra lean to pass MOT emissions without all 3 cats fitted and then immediately switch back to the normal map after the MOT.
I think you misunderstood my wiring loom question. I definitely do NOT want to use the old harness and plan on having a brand new loom. the MS2X kit appears to come with a bare end loom and I would have no problem with adding the connectors (I did that with my last MS setup) however I wanted to save time and just have a plug 'n play wiring setup this time and wondered if there was any difference in price/quality in getting the loom from ExtraEFI or MS2Tuning?
I'd normally be inclined to get everything from the same place however I have seen lots of posts where people have bought the kit from ExtraEFI and loom from MS2tuning and I wasn't sure why.
Could I ask who did your tuning? I'm on the South coast and a lot of the places I've seen are quite far away.
Cheers
M
I went MS2X from extra Efi, Phil is very good.
Shaun makes the looms, they work hand in hand, he also does road mapping and is mustard.
I also fitted the more modern Bosch injectors, it all went relatively smoothly.
Bailey performance are another company mustard with MS mapping.
Sometimes you need to travel for mapping but it is well worth it as the pros make it look easy whereas I spent hours on mine and was never happy with it.
Shaun makes the looms, they work hand in hand, he also does road mapping and is mustard.
I also fitted the more modern Bosch injectors, it all went relatively smoothly.
Bailey performance are another company mustard with MS mapping.
Sometimes you need to travel for mapping but it is well worth it as the pros make it look easy whereas I spent hours on mine and was never happy with it.
Belle427 said:
I went MS2X from extra Efi, Phil is very good.
Shaun makes the looms, they work hand in hand, he also does road mapping and is mustard.
I also fitted the more modern Bosch injectors, it all went relatively smoothly.
Bailey performance are another company mustard with MS mapping.
Thanks, good to know!Shaun makes the looms, they work hand in hand, he also does road mapping and is mustard.
I also fitted the more modern Bosch injectors, it all went relatively smoothly.
Bailey performance are another company mustard with MS mapping.
What injectors did you go for?
Cheers,
Mat
Speak to Dale at Baily performance first, Telford way as he is the guru when it comes to MS mapping. He did my turbo 450 some years back (573hp) and I recall him stripping the unit down to insert plasma shields or something can't quite remember for extra heat shielding with dwell or some other witchcraft. I glazed over and just remember the words 
but the result was stunning. He da' man.
but the result was stunning. He da' man.GreenV8S said:
macdeb said:
extra heat shielding with dwell or some other witchcraft. I glazed over and just remember the words
Did it sound something like "a bigger heatsink on the ignition drivers so we can run more dwell without overheating them"?
Edited by macdeb on Friday 15th July 17:42
GreenV8S said:
I did it on the road, over many iterations.
Nice one! That brings back memories of not long after I met my 'now' wife.
I had just supercharged my MX5 and we did many a trip too and from her parents place with a laptop sitting on her lap running tunerstudio. From having no car knowledge whatsoever after a few weeks she became scarily good at tweaking the map and it ended up a pretty formidable machine.
Sadly now with two young children at home that's no longer an option.
Auto tune is pretty good to get fairly close I found.
Ignition table is best tweaked on a rolling road but again this is pretty straightforward, most people who have the same size engine will have a table somewhere close enough but the one extra efi provided is pretty good actually with less advance where the Tvr tends to shunt.
Ignition table is best tweaked on a rolling road but again this is pretty straightforward, most people who have the same size engine will have a table somewhere close enough but the one extra efi provided is pretty good actually with less advance where the Tvr tends to shunt.
The transients are what took the time, especially since I have upstream and dowstream fuelling with a massive amount of wall wetting from the upstream fuelling. Getting that switchover right was a pita as it goes from upstream cruise, downstream for wot and both under boost. But it is worth it to have frost on the supercharger after it's been running for an hour.
I also had a wierd problem where a wideband sensor started reading exactly 1 AFR wrong, with two different sensors at different times. I've seen a tuner on Youtube with a similar problem. Had me chasing my tail until I figured out what was going on.
The autotune is OK as far as it goes but imo really needs a way to indicate coverage and variance over the map. Without that it's really hard to get a sense of how well the map is converging towards a good tune.
I also had a wierd problem where a wideband sensor started reading exactly 1 AFR wrong, with two different sensors at different times. I've seen a tuner on Youtube with a similar problem. Had me chasing my tail until I figured out what was going on.
The autotune is OK as far as it goes but imo really needs a way to indicate coverage and variance over the map. Without that it's really hard to get a sense of how well the map is converging towards a good tune.
Just a heads up but Shauns loom won't include the wiring for Alternator and other engine sensor warning lamps, oil pressure etc.
You need to either keep this from the old loom which is a bit of a pita but less hassle or make your own.
Both wiring connectors for the 14cux and Alternator etc can be found behind the head unit.
I went full gung ho and ripped it all out first !
You need to either keep this from the old loom which is a bit of a pita but less hassle or make your own.
Both wiring connectors for the 14cux and Alternator etc can be found behind the head unit.
I went full gung ho and ripped it all out first !
Belle427 said:
Just a heads up but Shauns loom won't include the wiring for Alternator and other engine sensor warning lamps, oil pressure etc.
You need to either keep this from the old loom which is a bit of a pita but less hassle or make your own.
Both wiring connectors for the 14cux and Alternator etc can be found behind the head unit.
I went full gung ho and ripped it all out first !
Thanks for the heads up, I'll bare those bits in mind.You need to either keep this from the old loom which is a bit of a pita but less hassle or make your own.
Both wiring connectors for the 14cux and Alternator etc can be found behind the head unit.
I went full gung ho and ripped it all out first !
How did you deal with the immobiliser? In an ideal world I'd quite like to lose this as it's another point of failure (and looking at my service history has played up more than once).
Did the MS swap take you long?
Existing loom was out in an hour or two but I took my time on the rest over a week or so when I had time.
I'd already replaced the alarm/immobiliser previously.
I retained it purely for the central locking control as I didn't fancy any of the locking kits available.
I knew the wiring inside out so could bypass it easily in a matter of minutes should any problems have developed.
I'd already replaced the alarm/immobiliser previously.
I retained it purely for the central locking control as I didn't fancy any of the locking kits available.
I knew the wiring inside out so could bypass it easily in a matter of minutes should any problems have developed.
Hi all.
So the MS2 kit has been ordered from Phil at ExtraEFI and parts have started to arrive and Shaun will be building me a loom when back from his holiday.
In the meantime I've been looking at how best to mount the VW coilpacks that are part of Phil's kit. I've seen some people mount them on the side of the plenum which looks fairly neat.
Who sells a mounting bracket for them?
So the MS2 kit has been ordered from Phil at ExtraEFI and parts have started to arrive and Shaun will be building me a loom when back from his holiday.
In the meantime I've been looking at how best to mount the VW coilpacks that are part of Phil's kit. I've seen some people mount them on the side of the plenum which looks fairly neat.
Who sells a mounting bracket for them?
CrunkleFloop said:
Hi all.
So the MS2 kit has been ordered from Phil at ExtraEFI and parts have started to arrive and Shaun will be building me a loom when back from his holiday.
In the meantime I've been looking at how best to mount the VW coilpacks that are part of Phil's kit. I've seen some people mount them on the side of the plenum which looks fairly neat.
Who sells a mounting bracket for them?
Coils packs are best not mounted to some hot metal bit of the engine, although they will work like this, but their life and performance (max current handling capacity) can be reduced. Mounting them to something metal as a heat sink, that is then mounted to the engine with some sort of plastic standoff is a good option.Luckily the venerable old RV8 is a relatively cool engine up top because the exhausts are spread out wide and down, and the rocker covers are actually pretty cool mostly because there isn't that much hot oil flying around inside (compared to OHC engines) and the rockers are gasketed to the heads (this is also why the engine tends to suffer from a build up of sludge / mayonaise in those covers as the combustion water products condense in this cool area)So the MS2 kit has been ordered from Phil at ExtraEFI and parts have started to arrive and Shaun will be building me a loom when back from his holiday.
In the meantime I've been looking at how best to mount the VW coilpacks that are part of Phil's kit. I've seen some people mount them on the side of the plenum which looks fairly neat.
Who sells a mounting bracket for them?
Edited by anonymous-user on Thursday 28th July 18:58
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