Technical Mmm Warm TB

Currently reading:
Technical Mmm Warm TB

Joined
Mar 21, 2006
Messages
3,162
Points
590
Location
Looking at an empty Glass
Ok was looking at swapping the tb's over today between the N/A and the Turbo, as the N/A has a Tricker 40mm and the Turbo a Citroen 36mm.

First thing i noticed the Fiat TB is linked into the cooling sytem (presumably to keep it warm & stop iceing) and the Citroen one it not heated in anyway. Easy enough to get round round this but was wondering 1. if not being heated would cause any iceing issues on the N/A especially as it running a GSR? 2. would it being heated cause any issues on the Turbo? (but I can not link it in as it is currently by-passed so again not an issue)

Second thing, there is a second oil breater branching off the main rocker breather on the N/A to the bottom of the tb, the Turbo doesn't need this but is it important to the N/A? (as it will still vent via the large pipe to the bob i guess not)

(played stopped now because of strong winds and bad light :mad: or would have got pics to go with the question)
 
the PSA TB would have had an electric heater in it, presumably only used when the engine was starting from cold.

as aaron has said, it should run fine without the heated TB, it'll heatsoak easy enough from the head and the manifold is heated anyway.

as for the oil breather to the TB.. not sure it needs that, doubt it really.
 
i do believe the coolant running through the TB was done away with on the later MPi seis too!

Should be fine, as said

Lenny (y)

it was ditched, but done because the fuel was injected very near the ports. As you inject fuel, the atmosised spray absorbs heat from its surroundings (same reason why if you hold an air freshener spray open long enough it will form ice on the nozzle). Thats why MPIs don't have heated manifolds, or TBs and could never benefit from one!
 
OK swaped!!

not quite as straight forward as i thought it was going to be

40mm Tricker onto turbo was no problem, was a straight fit,

PSA 36mm onto the NA that was slightly different. had to bypass the water feed and the second oil breather as i suspected but no problems with that.

but the spacer plate on the PSA was 5mm, that was fine on the turbo but was not tall enough for the N/A and the throttle stop hit the manifold, after a bit of head scratching I realised the Turbo runs an Uno inlet manifold compared to the Cinq and it is quite a different design.

So if you are going to put the PSA 36mm on a cento then you either need to modify the throttle stop or make up a 15mm spacer (or fit an Uno manifold) you can see the problem in the pic below

I have also taken a pic of the std TB the PSA 36mm and the Tricker 40mm side by side so you see the differences

Edit: Oh and that extra 4mm does make a difference :D
 

Attachments

  • CIMG0394.JPG
    CIMG0394.JPG
    1,020.4 KB · Views: 30
  • CIMG0390.JPG
    CIMG0390.JPG
    1,011.5 KB · Views: 387
Last edited:
Out of interest, did you perceive any differance on the turbo car after changing the TB?


Yes it was remarkably noticable the engine winds up even quicker than before and it is even more tractable. For eg i was comming out of a 30 limit to a section of national, put my foot down and thought mmm it isn't pulling very well best go home and have look around as the car just gently accelerated away (until it came on boost), then i realised i was in 5th gear not 3rd:eek:

Could be me but i'm sure it is registering and extra 0.1bar of boost on the guage at WOT too

On the flip side no perceptable difference on the NA
 
No not just you. I remember when I went from 30-40mm tb the boost gauge was registering 0.2bar more, from 0.6-0.8. The turbo is not making any more boost, but the inlet track has less restriction on it, so the boost getting to the engine is slightly higher.

All modifications to do with flow have a much much bigger effect on forced induction cars than n/a cars, head work, tb's, exhausts etc

Aaron.
 
Sorry to hi-jack the thread but, although i've heard of people using Uno Turbo inlet manifolds before, i'm just wondering what the advantages are.. I'm assuming that its has a better flow for a turbo as it was designed with that in mind. Am i correct?

And basically does the difference it makes make it a worthwhile swap? I'm not gonna be doing it anytime soon tbh, i just need to get car back on road asap at the mo but just for future tinkering ;)

Thought maybe in the future of getting it all flowed and ported so could swap over to a UnoT inlet at same time, wouldn't have to take her off the road again then you see
 
Last edited:
The inlet is a 1L Uno FIRE inlet, though if trying to source one be careful there are two that look the same but only one has a water temp sensor built in IIRC.

The reason we came up with using it is because http://www.bielstein.com/ of Germany have different upgrade packages for the 1108cc engine including 38mm TB and inlet manifold which from the pics is identical to the Uno inlet.

Aaron.
 
OK cool, so when i get to this i'm looking for a Uno 1ltr inlet manifold with a water temp sender in it..

Sorry i only ask as i got a spare head at home which i plan to get worked a bit and whack in a Punto75cam so must do the inlet manifold to as it will all be a bit pointless.
 
Back
Top