Technical corsa tb top on 1108 sei!

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Technical corsa tb top on 1108 sei!

so if its part of, it cant be instead of the intake manifold - thats what i was trying to get across.

the inlet manifold on a FIRE unit is like a reverse 4-2-1 exhaust manifold is it not. So its the plenum chamber the name given to the space inside the intake manifold - or any open space after the butterfly?
 
fordy said:
just modified my induction system for the last time!

took of the old restricive cinq 899cc tb top with the cold air ram pipe and crappy filter and i have just made a corsa 1200cc throttle body top fit my sei 1108, with a nice length of blue silocon hose leading to a jetex response air filter off a nissan skyline r32 gts-t, made one hell of a difference, sounds lovely, goes better up the top end - a lot better

If you've taken a crappy filter off, changed the ducting and plenum - how can you be sure the 'bob', 'plenum', or 'hat' was at fault?

The 899 carb top is a perfect fit, the intake tube is much bigger bore than the actual butterfly section of the throttle body, and has an easy end to attach a hose to. Unless you're running a 2" bore throttle body, there isn't going to be any restriction posed by it.

How have you attached the new silicone hose to the Corsa top?
 
tiger seal! lol

the main performance increase has come from the enlarged volume of air sitting in the "bob" at any given point due to the volume of space inside being larger, the engine can get the air it needs just that little bit faster and it responds better, the 899 "bob" was good no doubt about that and my filter change has made a difference but i tried this filter with the old "bob" setup and the corsa one is just that extra bit better.

i aint asking for all and out war just thought i would share my findings with everyone so if they want to they can share in trying to find new ways from other manufaturers to make there fiats faster, louder, more economical (if you must) and anything else that they feel. Fiat isn't the be all and end all - great cars though they are, they can be modded using other manufacturers parts to make them superior to every other modded fiat out there
 
There's a technical explanation about increasing gas speed into the throttle body somewhere, which improves torque - hence the tapered ducting and smaller volume 899 top. if I find it I'll post it up.

I'm actually running a 36mm PSA (Peugeot/Citroen) throttle body on my cinq - don't ask what it came off, though as I couldn't tell you. Just looked about right in the ebay auction so I took a chance.
 
Hi there

Plenum is the name of the chamber in the inlet manifold before air/mixture goes through smaller pipes to the cylinders.

The perfect "bob/hat" will be a box sitting on the intake with a pipe on the side pointing away to avoid warm air from engine. The pipe has to sit of centre on the side of the "bob" just like the it does on the plastic "bob" from the 0.9 engine.
The dia. of the pipe on the side of the "bob" from 0.9 is only 40mm and this is barely enough to feed the engine if you have a bigger sized TB fitted.

My 40mm TB's do not run perfect with the plastic "bob" from 0.9.

My opinion is that the GSR-kit's for Cinq/Sei is bad if you really want some more power ex. by fitting a bigger TB.

The original inlet manifold is designed the way it is because of torque. The original inlet manifold is not any good if you want 100 HP - of course you can fit a 300 degree cam but if you do that you will loose torque.
The only way is to make a new inlet manifold to get more power and still keep torque - fitting a turbo kit is not even an option for me because of the price and the Danish laws regarding tuning.
My inlet manifold I designed to do both things - I have 110 Nm and 95 HP on a Punto 60 engine with a 280 degree cam and this I not even possible on the Punto 75 engine.

One of my club members have a Punto 75 engine bored out to C-size pistons fitted in his Cinq. and our engines has the same offset (same: cam, exhaust and so on) - He have 115 Nm and 88 HP.

The different can be seen from the print out from rolling road and here my HP curve climbs straight to the rpm. Limit where the Punto 75 engine curve tops at 6000 rpm. and falls. My torque is climbing from 2700 rpm and holds all the way through to the rpm. Limit.

Here is a picture of my induction kit
L1.JPG

see the pipe on the side of the "bob" - it's of center. This induction kit has given me 3-4 more HP messured on the rolling road.
 
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I thought the punto 75 was the same bottom end uses a different head as in the inlet manifold is different and it runs a different cam but everything else is the same except it runs 4 injectors?
so how can it be less than yours (sorry just dont understand?)
 
Silver_Sei said:
I thought the punto 75 was the same bottom end uses a different head as in the inlet manifold is different and it runs a different cam but everything else is the same except it runs 4 injectors?
so how can it be less than yours (sorry just dont understand?)

The 75 is less because of my inlet manifold and extrem ported cylinderhead ;)
 
I've been having a play about, and realised that the inlet manifold on the SPI cars has a bore of just 38mm below the throttle body. In theory, this is going to pose a bigger restriction than the 40mm inlet from an 899cc top.
 
I solved the BOB problem by fitting an oval K&N designed for carbs! The one I used is off a fiesta (I think) and the hole in the bottom sits perfectly on the throttle body. All I had 2 do 2 fit it was drill holes for the mounting bolts.

This has solved the juddering problem I had on "Take off" and has got rid of the ugly inlet pipe. It cost me a tenner off Ebay!

The only problem with this method is with the cold air feed and I intend to solve this by cutting away the crappy plastic fake grill under the bonnet lip and replacing with mesh, a small duct and some ducting pipe!

I'll post some pics 2moz!

Jon.
 
project-cinqy said:
I solved the BOB problem by fitting an oval K&N designed for carbs! The one I used is off a fiesta (I think) and the hole in the bottom sits perfectly on the throttle body. All I had 2 do 2 fit it was drill holes for the mounting bolts.

This has solved the juddering problem I had on "Take off" and has got rid of the ugly inlet pipe. It cost me a tenner off Ebay!

The only problem with this method is with the cold air feed and I intend to solve this by cutting away the crappy plastic fake grill under the bonnet lip and replacing with mesh, a small duct and some ducting pipe!

I'll post some pics 2moz!

Jon.

Do you mean you put on a filter to replace the airbox like this?

EngineBay1.jpg


If so then that's worse then the bob cos it is sucking all the hot air from the manifold and top of the engine even with a cold air feed.

Best to do something like this

CustomInductionKit.jpg


But even better just buy the GSR kit.

Liam
 
Mines fitted to an SX, so my inlet is at the back! And no it's not a round filter, it's designed for a single carb, but with a bit of work it works fine.

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=7973430732

I know it's sucking in warm air at the mo, should be solving that shortly as I said, with a large enough cold air hose, drawing through a tapered duct straight from the front of the car it should pull enough cold air in. I'm gonna be lagging the manifold soon anyway so that'll stop the exhuast heating the engine bay up.

I hate the way the gsr goes from a tiny bob to a huge filter. I had a custom build that did the same job but looked awful. Mine is a lot cleaner looking, and is totally unique!
 
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