Piggy Back ECU for cold start?
Discussion
I know very, very little about ECU's and the functionality required to have facilitate a more 'eurobox' cold start. Im not even sure its possible without new hardware...BUT...
Excuse the naive question, does the Tuscan have any cold start functionality AT ALL? Could the ECU not look at water temp for fuel control / different fuel map at cold start?
Could this be achieved with an aftermarket piggy back ECU - they seem to be readily available for a few hundred £ perhaps offer an option for those not wanting to spend £3k on syvecs or MBE upgrade?
A friend of mine in the office has run a number if high power turbo cars which use an extra injector for high boost application and a piggy back ECU for its control...is this not a *similar* principle?
Could the injoectors not be programmed to run higher fuel rates at cold water temps?
Again, not sure if this is the real key to smoothness on start up....but it was an idea i was mulling!!
Excuse the naive question, does the Tuscan have any cold start functionality AT ALL? Could the ECU not look at water temp for fuel control / different fuel map at cold start?
Could this be achieved with an aftermarket piggy back ECU - they seem to be readily available for a few hundred £ perhaps offer an option for those not wanting to spend £3k on syvecs or MBE upgrade?
A friend of mine in the office has run a number if high power turbo cars which use an extra injector for high boost application and a piggy back ECU for its control...is this not a *similar* principle?
Could the injoectors not be programmed to run higher fuel rates at cold water temps?
Again, not sure if this is the real key to smoothness on start up....but it was an idea i was mulling!!
Perhaps my question should have been "how can i get eurobox smoothness on start up"
It it worth it, is it possible...
could you add throttle idle control?
My car is well set up, i believe, and v smooth when warm...but when cold its pretty lumpy and thats with a whole heap of bits and pieces new - throttle bodies with roller bearings, new thottle pots, plugs, leads etc...it still isnt brilliant from cold...
I dont think its a 'problem' as such, just something that can be improved upon?!
It it worth it, is it possible...
could you add throttle idle control?
My car is well set up, i believe, and v smooth when warm...but when cold its pretty lumpy and thats with a whole heap of bits and pieces new - throttle bodies with roller bearings, new thottle pots, plugs, leads etc...it still isnt brilliant from cold...
I dont think its a 'problem' as such, just something that can be improved upon?!
spitfire4v8 said:
two words : valve clearances.
it's the secret. your car should be smooth hot or cold.
hmm...you know better than i do im sure. it's the secret. your car should be smooth hot or cold.
But, engine rebuilt and clearances checked recently by Jason at str8 six....so i would very much hope there isn't anything wrong there.
Im not the only one wanting a smoother cold start, it *seems* to be a more general thing than something specific to my car?
Maybe you are right, maybe i should get them double checked?! You have me thinking now!!
spitfire4v8 said:
two words : valve clearances.
it's the secret. your car should be smooth hot or cold.
Wouldnt you expect valve clearances that weren't correct when the engine is cold - to make any rough running worse when engines get warm and the clearances open up? it's the secret. your car should be smooth hot or cold.
Please dont get me wrong, its not a problem...its just something i was thinking could be improved. Cold - lumpy - warm - smooth as anything, its not a night and day difference.
I thought most speed six owners had this!
Sounds like you're hoping for the impossible here?
It's a highly tuned engine with big valve lift & one large throttle per cylinder for optimum airflow at high rpm, just like a good bike engine even down to the cam design with finger followers.
Bike engines run 'acceptably' smoothly when cold - slightly lumpy if you are really comparing to euroboxes rather than Ferraris - but perfect once warmed a little.
If you had a recent service it should be pretty smooth even when cold, mine always is from STR8SIX. The injectors will be releasing the correct amount of fuel that they can within the limits of the engine's and injectors' design unless you go to full sequential rather than batch firing, and will be as good as it can be unless you fancy a swap to eurobox mild cams and the eurobox power that goes with them.
It's a highly tuned engine with big valve lift & one large throttle per cylinder for optimum airflow at high rpm, just like a good bike engine even down to the cam design with finger followers.
Bike engines run 'acceptably' smoothly when cold - slightly lumpy if you are really comparing to euroboxes rather than Ferraris - but perfect once warmed a little.
If you had a recent service it should be pretty smooth even when cold, mine always is from STR8SIX. The injectors will be releasing the correct amount of fuel that they can within the limits of the engine's and injectors' design unless you go to full sequential rather than batch firing, and will be as good as it can be unless you fancy a swap to eurobox mild cams and the eurobox power that goes with them.
Edited by tail slide on Tuesday 31st July 22:45
Mine runs lovely and smooth when it returns from service, even from cold, starting first time nearly every time, even in winter and it lives outside. As the months go by, it becomes a bit lumpy whilst cold and might need a little throttle to keep it going, esp. in winter. Learnt to accept that throttles go off a bit and ECU not the most advanced, and secret is to get off driving after 15 secs of starting.... soon warms up and settles down.
Walford said:
Would be quite simple, just need an actuator under the main thottle stop controled from water temp
Maybe on thottle outer cable mount
After thinking about my own question and the comments on here re air control i came to the same conclusion.... my thoughts arrived at a servo controlled throttle idle screw that reacts to the water temp sensor signal...which is easy in theory a little more complex in execution... when you have no experience of implementing an add on system that could either standalone or integrate with the current ECU... !!Maybe on thottle outer cable mount
I just modified a set of throttles to dump the balance arms and to get rid of the "idle" stop and 1x throttle pot.
Old setup is not great...if you look the lag from middle throttle to outer ones its signficant (anyone who's played with throttle air flow balance will appreciate the *tiny* amount of butterfly opening that will make a cylinder run lean and start to pop)
So I have now got adjuster screws for each body (dog-tipped grub screw at angle into barrel to act as stop for butterfly), shafts all joined using shaft couplers and previous inside pot connector now paralleled across the outer pot so both banks always see the same resistance (the matching of the pair at mild throttle was totally down to the linearity of the two (different) pots...hit and miss)
Its running well and much better at light throttle. Idle speed adjustment by oversize holes in remaining pot...just loosen and make a tiny rotation to adjust (adaptives then correct mixture)...works OK...get consistent idle from just after start to piping hot. No throttle to start
Fun project.
Old setup is not great...if you look the lag from middle throttle to outer ones its signficant (anyone who's played with throttle air flow balance will appreciate the *tiny* amount of butterfly opening that will make a cylinder run lean and start to pop)
So I have now got adjuster screws for each body (dog-tipped grub screw at angle into barrel to act as stop for butterfly), shafts all joined using shaft couplers and previous inside pot connector now paralleled across the outer pot so both banks always see the same resistance (the matching of the pair at mild throttle was totally down to the linearity of the two (different) pots...hit and miss)
Its running well and much better at light throttle. Idle speed adjustment by oversize holes in remaining pot...just loosen and make a tiny rotation to adjust (adaptives then correct mixture)...works OK...get consistent idle from just after start to piping hot. No throttle to start
Fun project.
PetrolHeadPete said:
I just modified a set of throttles to dump the balance arms and to get rid of the "idle" stop and 1x throttle pot.
Old setup is not great...if you look the lag from middle throttle to outer ones its signficant (anyone who's played with throttle air flow balance will appreciate the *tiny* amount of butterfly opening that will make a cylinder run lean and start to pop)
So I have now got adjuster screws for each body (dog-tipped grub screw at angle into barrel to act as stop for butterfly), shafts all joined using shaft couplers and previous inside pot connector now paralleled across the outer pot so both banks always see the same resistance (the matching of the pair at mild throttle was totally down to the linearity of the two (different) pots...hit and miss)
Its running well and much better at light throttle. Idle speed adjustment by oversize holes in remaining pot...just loosen and make a tiny rotation to adjust (adaptives then correct mixture)...works OK...get consistent idle from just after start to piping hot. No throttle to start
Fun project.
would love some pics if you took any Pete. Old setup is not great...if you look the lag from middle throttle to outer ones its signficant (anyone who's played with throttle air flow balance will appreciate the *tiny* amount of butterfly opening that will make a cylinder run lean and start to pop)
So I have now got adjuster screws for each body (dog-tipped grub screw at angle into barrel to act as stop for butterfly), shafts all joined using shaft couplers and previous inside pot connector now paralleled across the outer pot so both banks always see the same resistance (the matching of the pair at mild throttle was totally down to the linearity of the two (different) pots...hit and miss)
Its running well and much better at light throttle. Idle speed adjustment by oversize holes in remaining pot...just loosen and make a tiny rotation to adjust (adaptives then correct mixture)...works OK...get consistent idle from just after start to piping hot. No throttle to start
Fun project.
I suspect one of my roller bearings throttle bodies may be marginally off central which causes it to pull a little less air when cold to when hot, think it exacerbates the lumpy running at cold.
I adjusted during the week taking into account this movement and it seems much better.
I will probably just leave it TBH but its something to think about...
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