good luck with that, running ITBs means you won't have a stable MAP reading - you'll need to use alpha-n, something that the stock ECU isn't going to do. Even if it did, the throttle pots on the ITBs will differ. Also can't see a set of p75 injectors fitting into ITBs.
Technical throttle bodies for FIRE engine
- Thread starter blackmagic11
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Technical throttle bodies for FIRE engine
good luck with that, running ITBs means you won't have a stable MAP reading - you'll need to use alpha-n, something that the stock ECU isn't going to do. Even if it did, the throttle pots on the ITBs will differ. Also can't see a set of p75 injectors fitting into ITBs.
They are very long, the P75 ones. Much of the machining Tom is doing on my P75 inlet mani is to mill down the slugs I've welded on to enable me to run pico ones (same end fittings, but around 30mm shorter). But Japanese bike injectors tend to be even smaller than the weber picos (which most Italian bikes use), dimensionally, that is.
A decent workshop??
You'll need a lathe and milling machine and a TIG to make the manifold up
thats been put aside for my new flywheel.:devil:I'll have to mill those slugs at work, as i dont have a funky vise, but i have faced the inlets off tho, one of them was quite abit lower than the rest.....were you drinking when you cut them
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Sorry I didn't understand exactly what you meant
Has he actually tried ITB though? I guess it may be out of his reg's. Would be interesting to see a side by side though!Came across this recently for ITB's and rotary. Looks interesting. Not sure how well it works, but it does averaging of the signal etc. Could be worth a look
Cheers,
Kristian
are they individual map sensors??
ill just stick to alpha-N
ill just stick to alpha-N
I'll have to mill those slugs at work, as i dont have a funky vise, but i have faced the inlets off tho, one of them was quite abit lower than the rest.....were you drinking when you cut them
Bloody cheek!
I was working with the damn thing clamped in a workmate trying to keep everything in line with the cast in lugs as reference (which may well not be in line) and using a coarse hacksaw at a wierd angle. Couldn't be more than 1/8" out though!
Now if I had a machine vice and a bandsaw.................
Sorry I didn't understand exactly what you meant
Pretty sure he's not tried ITBs. I'd guess they might offer a little on a race car, but as it does sprints/hillclimbs, I doubt there's anything to be gained -- and a lot to be lost!
Still, close to 100hp from a n/a 1108 has to be pretty close to what's possible.
could you just not ditch the ECU? and run it on megaspark or somthing? using jetted TB's?
pointless ditching an fuel injection system when all the sensors are there and work nicely.
4 MAP sensors does seem overkill.. alpha-n ftw!
Problem doing it that way is either using bike carbs (in which case they're likely to be too big and you have the horrors of slide throttles and availability of bits) or SUs or Dellortos or Webers (in which case they'll cost the earth). Wonder what it would take to make a one off set of TBs?
One day id like to get a set of throttle bodies in a cento the induction sound at 9k rpm is so sweet and rather funny coming from a little car.
So what if you was to just use 2 throttles instead of 4? That way can ya get away with having slightly larger throttle size?
So what if you was to just use 2 throttles instead of 4? That way can ya get away with having slightly larger throttle size?
someone has put two 'standard' throttle bodies on to a cento, theres a pic kicking about somewhere
ITBs are all very well but was talking to someone doing tuning on Ford 2.0 (Duratec?) engines and going from the correct sized TB to ITBs he was talking about trading around 10% reduction in torque at 2500-4000 rpm with a 5 or 6% power gain in the 5500-9000 rpm range. The compromise was worth it for racing in 'kit cars' and the like but on the road the engine felt lack lustre and breathless.
I'm not saying don't do it but be aware that you could wreak havoc the lower end of the rev range.
I'm not saying don't do it but be aware that you could wreak havoc the lower end of the rev range.
Dont want to **** in anyones puddle.
But the details on ITBS are already on the FF
https://www.fiatforum.com/cinquecento-seicento-faqs/95772-fire-tuning.html
But the details on ITBS are already on the FF
https://www.fiatforum.com/cinquecento-seicento-faqs/95772-fire-tuning.html
yeah on tbsei's car. but this thread didnt strike me as "i'm the first person doing this" kind of thing.
arc said:
Did you actualy click the link? or do a generic reply? if you read the link you'll see at no point did I imply anything about tbsei
IF you actually clicked the link you would see I link to the wolf direct racing link on tuning a fire engine.
Where....
low and behold it discusses ITB's and that they use Hayabusa ITB's which is directly related to this thread as they were discussing size.
Oh and heres some more info for you.
ITB size guide
Up to 30 BHP/CYLINDER - 30mm
up to 33 BHP/CYLINDER - 32mm
up to 39 BHP/CYLINDER - 35mm
up to 46 BHP/CYLINDER - 38mm
up to 51 BHP/CYLINDER - 40mm
up to 56 BHP/CYLINDER - 42mm
Up to 65 BHP/CYLINDER - 45mm
up to 74 BHP/CYLINDER - 48mm
up to 80 BHP/CYLINDER - 50mm
up to 87 BHP/CYLINDER - 52mm
up to 93 BHP/CYLINDER - 54mm.
(i posted the info this time to stop someone critisising my post without reading the link first)
i clicked the link, saw it was a scan of the retro cars article about WDR and then closed it because i couldn't be arsed deciphering the gibberish to pick out some facts.
i only mentioned tbseis car because he was a member on here, and had a car running on ITBs and there is a photo of the bloody thing on the link.
i only mentioned tbseis car because he was a member on here, and had a car running on ITBs and there is a photo of the bloody thing on the link.
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Dont want to **** in anyones puddle.
But the details on ITBS are already on the FF
https://www.fiatforum.com/cinquecento-seicento-faqs/95772-fire-tuning.html
I doubt if Wolf Racing actually found those figures themselves (I mean, by rigorous empirical study)! Interesting that the figures don't differentiate between 2 valve and 4 valve engines, undersquare/oversquare engines, etc.
Nevertheless, those are not a bad starting point (but neither was my 29mm figure, lifted from Bell's book).
The point Stone Newt makes is a good one -- many many years ago CCC ran a comparison between a plenum chamber singleTB set up and a carb per cylinder set up on a racing pinto engine. With carb per cylinder, the engine lost out everywhere below 7k.
