AlexF
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Have you found the guides, FAQ's and the search button
Search yes - FAQ no!
I better look harder
Tuning turbo time!
- Thread starter craigb244
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Tuning turbo time!
Search yes - FAQ no!
I better look harder
OP
OP
its a sticky on the faqs (which imho makes it harder to see cos i usualy skip them thinking its just rules and crap)
https://www.fiatforum.com/cinquecento-seicento-faqs/93833-cinq-sei-turbo-faq.html
https://www.fiatforum.com/cinquecento-seicento-faqs/93833-cinq-sei-turbo-faq.html
ditto, i see that and thinks part of the forum AUP
AlexF
New member
I found it thanks guys... makes good reading
OP
OP
right... quick question...
On my car i have a 47mm TB is there any point in fitting this on the turbo as its HUGE!
the output of the turbo is only about 30mm.
On my car i have a 47mm TB is there any point in fitting this on the turbo as its HUGE!
the output of the turbo is only about 30mm.
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the turbo is the one that will benefit more from the larger TB in my opinion. I'd fit it if it was me
KRistian
KRistian
OP
OP
really? guess its no harm in trying it.
I was thinking there was no point going any bigger then the output of the turbo.
I was thinking there was no point going any bigger then the output of the turbo.
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On that logic the volume of the exhaust valves should equal the inlet valves, should equall the throttle body etc.
I don't know lots i must admit, but the gasses on the inlet are compressed by the turbine, and will expand won't they. Velocity will slow down a little with a larger TB, but the turbo will work less hard and so be more efficient.
Others may decide to go the other way. Best idea is to get it RR'd with both.
Wonder what size others run, ie. stonenewt. I know aleenhellen felt big gains when he increased his TB.
Kristian
I don't know lots i must admit, but the gasses on the inlet are compressed by the turbine, and will expand won't they. Velocity will slow down a little with a larger TB, but the turbo will work less hard and so be more efficient.
Others may decide to go the other way. Best idea is to get it RR'd with both.
Wonder what size others run, ie. stonenewt. I know aleenhellen felt big gains when he increased his TB.
Kristian
OP
OP
actually now you mention it your right(im doing this stuff at college at the moment lol). it requires energy to keep up a velocity. flow thru a uniform pipe requires more effort then an tapered pipe...blah...blah
I also guess to a TINY % that the charge will be a tiny bit cooler after expanding a little
I also guess to a TINY % that the charge will be a tiny bit cooler after expanding a little
but once past the butterfly, it'll open out anyway. is that extra 20mm of larger diameter inlet really going to help much? imo, no.
my 40mm tb made a big difference to the spool up of the turbo and mid range torque was improved noticably.
jason
i would like to understand why tho.
Ah well i'm an old fart so that helps
TB wise generally bigger is best but you have to be able to inject enough fuel to air and you have to be able to flow that volume through the engine and exhaust. if you have stock internals it is pretty pointless
if you blow into a straw it requires effort, hence holding the turbo back as it tryes to spool upto speed, open it up and not as much resistance so the spool up can happen much quicker, dont really think it makes a huge differnce to all out power unless there was a hell of alot of airflow though.
OP
OP
i know on my n/a going from 32 (orignal cento) to 37(moded mpi tb) made a big difference. then when went up to the 47(mpi tricker) there was a HUGE gain in torque but did loose noticeable amounts at low rpm.
Im not sure about the other turbo owners put allanhelen has spi so im guessing at the max he has a tricker 40mm? 7mm over is a HUGE amount.
OH!!! allanhelen reminded me... sorted insurance out today. I added my painted stripes and body bits, wheels, rear disc and gt front convertion, body braces to my policy... also increased cars value to 1500. all this was free of charge!
just gotta ring up about the turbo convertion. i dont expect it to be much at all
Im not sure about the other turbo owners put allanhelen has spi so im guessing at the max he has a tricker 40mm? 7mm over is a HUGE amount.
OH!!! allanhelen reminded me... sorted insurance out today. I added my painted stripes and body bits, wheels, rear disc and gt front convertion, body braces to my policy... also increased cars value to 1500. all this was free of charge!
just gotta ring up about the turbo convertion. i dont expect it to be much at all
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yes a 47mm on an N/A!! the air flow at low rpm will be very slow, that would exsplain the poor bottom end
jason
I don't want to be a kill joy here but..... you should be considering these sort of things once you have it running and road legal, getting too caught up in details like this is just how projects start to fail as real life catches up with dreamer land. You either need to be one step ahead of reality or have enough cash to not care about it
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i know, i get that.. buutttt, using the same analogy, the turbo is already blowing through a straw (its compressor outlet) and the butterfly only sits around 20mm forward of where the diameter has increased in the inlet manifold. so is that extra 20mm really worth it?
On an n/a car it is a totally different ball game, upstream of the butterfly is just open air (effectively) so increasing the butterfly will help it breathe better.
OP
OP
ive had it running. the engine is going into my car Friday afternoon (coming out the black car tomorrow) hence the reason for doing insurance and wiring in the needed items in my car
reason im asking this is i would prefer to fit what ever best on the car now as then I can start tuning up the base map and not worry about changes after.
cant really call this a project... more of a swappa-roo
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ITB's really shine on turbo's and forced induction. and they have a MUCH bigger surface area in comparison to one large TB, so I'd say, the bigger the better. It must make some kind of difference.
Get it RR'd with both and put the debate to bed
Get it RR'd with both and put the debate to bed
