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tomcolinjones

Aftermarket Ecu On Standard 8V

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tomcolinjones

Hello.

I'm seriously considering using the 1.6 GTi engine I have sat in the garage in my 205 at some point In the future.

running it on Emerald or something similar. I was wondering if many people run a standard 8v engine on aftermarket management? and what parts would / could be changed to improve the engine and possibly make it more efficient / refined?

I would like to replace the AFM with something , possibly upgrade the injectors, Lambda sensor, possibly the throttle body itself? do away with the Distributor setup and use a MI16 flywheel and a coil pack.

what sort of gains could be expected from doing this work? surely its would make the engine more reliable and efficient, maybe some more power / torque? or is it completely pointless and id be better off spending time and money elsewhere?

 

thanks for reading.

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Tom Fenton

All do able but I would say you will be in for £1000 to get anywhere near, £450 ECU, £250 wiring and components, £300 mapping.

 

Or would that £1000 or some of it be better spent on getting the engine running well on the standard setup?

 

Only you can decide!

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Anthony

I've done this with an Emerald on a 1.9 rather than 1.6 engine, but the same basic theory applies.

 

The outright gains over an admittedly excellent running Jetronic setup were small, the dyno figures were within 2hp IIRC.

 

The aftermarket ECU did drive a little better, feeling more responsive and without the usual Jetronic "character" but it would be very hard to justify the cost for the gains/improvements IMO.

 

Would I do it again on my own car (this was done for a friend) - no - not unless the engine was modified enough to make the gains worthwhile - a big cam and a bump in compression to match for example, both of which the standard Jetronic and dizzy setup won't cope very well with.

 

Personally, on a standard-ish 1.6 GTi engine I would just get the standard Jetronic setup running optimally and it'll work well despite how primitive it is by any vaguely modern standard. Most Jetronic setups and dizzys are pretty tired these days and usually not setup properly either, hence so many cars running somewhat below par.

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tomcolinjones

using a 2nd hand ecu would cut the cost down a lot. And there would be no mechanics bits to wear out or require adjustment. Better fuel economy?

I have no gti loom or ecu, as its a base model car so a lot of parts will need to be bought. I've also sold on the distributor and afm . So I'm looking at it from the point of view that I'm going to have to start collecting parts and spending money.

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petert

If you can do it properly with a Motronic crank sensor and later wasted spark setup, it's worth doing, just to get rid of the leaking dizzy.

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105e

If I had long term ownership planned I would do it, also then easier to mod in the future.

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feb

I've done this with an Emerald on a 1.9 rather than 1.6 engine, but the same basic theory applies.

 

The outright gains over an admittedly excellent running Jetronic setup were small, the dyno figures were within 2hp IIRC.

 

The aftermarket ECU did drive a little better, feeling more responsive and without the usual Jetronic "character" but it would be very hard to justify the cost for the gains/improvements IMO.

 

Would I do it again on my own car (this was done for a friend) - no - not unless the engine was modified enough to make the gains worthwhile - a big cam and a bump in compression to match for example, both of which the standard Jetronic and dizzy setup won't cope very well with.

 

Personally, on a standard-ish 1.6 GTi engine I would just get the standard Jetronic setup running optimally and it'll work well despite how primitive it is by any vaguely modern standard. Most Jetronic setups and dizzys are pretty tired these days and usually not setup properly either, hence so many cars running somewhat below par.

 

How are you doing Anthony, long time no speak, I hope you are well.

 

^This. I wrongly had the impression that the Emerald would solve all of Jetronic's problems including cold starts - it helped don't get me wrong but never idled as a modern car, the lack of an ICV probably being the main culprit.

 

Then again part of the reason for going Emerald was being fed up with my sorrento SBC one as whenever it was setup by Paul @ SBC it would go like the clappers but cold starts were a right pain in the butt.

 

How I kick myself for selling that car the first time around!

 

Save your money and use it elsewhere.

Edited by feb

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opticaltrigger

I think if you fancy a technical challenge it's a great mod to do and you get loads of play time with the tweeking of this that and the other if you want.

I've never used Emerald and my only experience is with Megasquirt so I would personaly recomend that approach.

However if you just want a motor that runs well and thats all, then a quality standard setup is gona take some beating. But personaly I would do it though.

 

The current Megasquirt stuff in my oppinion is just outstanding in terms of fexibillity and functionality. And as for Megalog viewer, I think it's just incredible. But as I said I've never tried the others and I guess it comes down to personal choice in the end.

 

All the best

O.T.

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Miles

Cold starts and Idling is all down to mapping mainly, Like a system I had the other day badly mapped and killed the engine, yet my Mates 220bhp 8v Race 205 starts and Idles extremely well but that's running Motec.

When I went to Luminition (This was in the 90's) from Jetronic I found around a 8bhp gain and some mid range torque, exact figures I cannot state now as I cannot remember that far back

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cheesegrater

Does emerald not run a target idle speed? My e48 didn't but my s40 does and the difference was night and day in terms of cold start and idling.

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Rob Thomson

This is something I'm very interested in doing too.

 

Mine doesn't run particularly well despite the AFM and dizzy both appearing to be in good condition. It's inconsistent, some days it feels fairly quick and very responsive, other times it's feels sluggish and has s*itty response. I'm sure it would benefit from a set-up, but I have the impression that trying to sort the standard systems would just be throwing good money after bad. Maybe better to invest in a DTA etc instead, especially as it opens the door to other engine mods.

 

There's quite a parts list though... ECU, flywheel, sensors, loom, ICV (?), set-up.... definitely not cheap.

Edited by Rob Thomson

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petert

Most factory wiring is starting to decay now anyway, brittle plastic connectors etc., making fault finding increasingly difficult. I say give it all a birthday. I wouldn't bother with an ICV. Just use a trick ignition map. There's plenty of 16V Motronic flywheels around. Upgrade the clutch at the same time. As Miles said, the benefit is in the midrange and driveability, if you take the time to map it properly. If you want the OEM look, remove the internals of an old AFM. You can still use the air temp sensor if your ECU has user programmable inputs.

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Rob Thomson

Yep, my half-baked plan is to keep it looking standard so a hollow AFM would work nicely. Interesting idea about retaining the AFM's air temp sensor.

 

I bet a 16V flywheel and clutch is significantly heavier than the standard 8V's (mine's a 1.6 - can't remember whether or not that's lighter than a 1.9) - I love how free-revving it is at the moment.

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petert

Early BE1 boxes don't have a Motronic sensor hole, so that's another issue.

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Anthony

I bet a 16V flywheel and clutch is significantly heavier than the standard 8V's (mine's a 1.6 - can't remember whether or not that's lighter than a 1.9) - I love how free-revving it is at the moment.

There's not much in it Rob - from memory a 1.6 flywheel is about 6kg, an Mi16 flywheel about 6.5kg and a 1.9 about 7kg.

 

I think an 200mm Motronic flywheel is about the same weight as an Mi16 one but the clutch presumably slightly lighter being smaller.

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Miles

To keep it looking more OE you don;t even need to change the flywheel, A 16v Golf dizzy fit's and gives the right signal, as in the Road Saloons I was doing the engine bay had to look std with the Hollow AFM

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hoodygoodwood

Good to see others are considering running an aftermarket ECU on the standard inlet/fuel rail etc , I intend to do this on one of my 309's . I have spoken to Anthony and Miles about this and I am trying to gather the parts together while finding out as much about it as I can .

I will be changing the cam , probably to a Piper 285 and raising the compression ratio either by a head skim or with 1.6 pistons - daft not to modify the engine when the thing that has been restricting mods ( the std management )is removed .

I have already modified the throttle body to give a 6.5 % increase in area at wide open throttle .

Need to find out which TPS is suitable for the conversion and where the air temp sensor should be mounted .

Would an mi or GTI6 flywheel do the job with the sensor mounted in the hole on a BE3 bellhousing , or better still one of the aluminium super light flywheels .

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Anthony

Any XU Motronic flywheel will work fine together with a crank sensor - any 16v unit, 1.8/2.0 8v or late 1.9's. Use the appropriate clutch to go with them, either standard 205 GTi for a 200mm flywheel or a BX 16v for a 215mm.

 

I don't think that there's a direct fit TPS to an 8v throttle body. I used a late XU 16v (GTi-6 etc) unit on an adapter plate I quickly knocked up, or you can use the same TPS as used on ZX 1.9 Volcane models and some other XU 8v's which I think has the right bolt pattern but needs the spindle end modifying from a D-shape to a flat.

 

Air temp sensor location arguably doesn't matter too much as long as it "sees" air temp the same as the engine - either drill and tap the inlet manifold (the plug on the opposite end to the throttle would be easy), in the induction pipework somewhere, or mounted in or immediately next to the air filter.

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welshpug

there are 1.6 8v with 200mm timing tooth equipped flywheels too. mm ecu of some kind, coilpack and a map sensor.

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hoodygoodwood

If the conversion went well and I was seeing 145/150 bhp would the 200mm clutch be up to the job or would it be worth going for the 215mm to be sure .

I think I feel a wanted ad coming on .More to the point I have been eyeing my wifes 306 cabrio the last few days as the oil pressure has disappeared in the last week and it is the 8v engine with coil pack in place of dizzy and maybe the correct flywheel and pickup ?

I will be checking the crank pulley nut has not come loose this weekend .

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Anthony

200mm clutch would be fine IMO.

 

Ph1 306 cab would have some of the bits that you need such as the flywheel (215mm if it's a 2.0 8v), thermostat housing, crank sensor etc. Later cab's have the 16v engine so the thermostat housing wouldn't be usable, but the flywheel and pickup would be.

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hoodygoodwood

The GTI6 flywheels seem to be much more common so I might end up with one of those , I will have to buy a new clutch for it any way .

I have previously weighed flywheels , a 1.6 is 5.9 kilos and a 1.9 is 6.9 kilos , does any know what a Motronic one weighs ?

I just swapped an early inlet for a 'coil on manifold' inlet which is a pain because I could use that now , I could be cleaning it up and looking for an air temp sensor location .

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petert

All 16V flywheels are identical. We have a model over here called an Si. It's the 1.6 with mono point Marelli injection.

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tomcolinjones

what about an idle control valve? Is there anything that will fit the 8v inlet? Or can a icv be fitted to the tps?

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tomcolinjones

I'm keeping a eye open for a nice cam, and the head will have some work too. 3 angle valve seats and ports matched to manifolds. I've got a magnex exhaust manifold that I will have to get a lambda boss welded onto.

what about injectors? Gti6 or s16 would these improve things? Or are the 1.9 injectors ample?

not really a standard engine with that list but still want to keep the standard inlet. Isn't there a vag throttle body that can be made to fit?

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