Tuning Seicento Track Car - Punto 75 Engine

[Jube]

Hi All,
First of all hello to everyone as it's my first post on the forum.

I'm looking to upgrade the 1108 MPi engine in my Seicento Sporting track car.

I've read lots of the engine upgrade threads and just wanted to check that I've understood what's required to install a Punto 75 engine.

Am I right in thinking that the following is required please?:

Punto 75 engine.
Punto 75 Throttle Body and Inlet.
Punto 75 injector wiring loom to splice in to the existing 1108 MPi injector wiring to use as batch injection.
3 Bar Fuel Pressure Regulator.
A Remap using the existing 1108 MPi ECU.

My current 1108 MPi engine mods are as follows:

BMC CDA Induction Kit.
Champion EON 2 Spark Plugs.
Magnecor KV85 Ignition Leads.
Balanced & Lightened Flywheel. (5.5KG)
Supersprint 4-2-1 Stainless Exhaust Manifold.
Custom 2" stainless exhaust system.
42mm 1.2 16v throttle body.

Can all of these modifications be used on the Punto 75 engine please?

Many thanks in anticipation,
Jube.

 

[centox8r]

Hi Jube

sounds good your current engine is what i have planned for my sei how does it run can you feel a difference

cheers rich

 

[ycming]

No if you have already got MPI, then you don't need to cut into the loom, just plug and play!

Not sure if you need the P75 fuel pump and regulator.

Beware with the supersprint manim i think only the early type will fit over a 1242. (assuming you are getting the one for the sei).

Ming

 

[Jube]

Thanks for the prompt replies guys.

Rich:
I've only just got the car, I swapped it for one of my Fiat Coupes would you believe. So I'm not aware of the improvement over standard that my current mods give I'm afraid - sorry.

I can tell you that the engine light is on constantly due to the 2" custom stainless exhaust having no cat. The previous owner has fitted a Punto lambda sensor (longer cable) to replace the first lambda and the second lambda sensor is disconnected.

The car runs great on full chat but bogs down quite badly at lower revs and often stalls. I'm not sure if this is a symptom of the decat and single lambda or maybe an idle control valve problem? I'll have to investigate this problem further but maybe there's some type of lambda bypass connector I can fit to the second disconnected sensor.


Ming:
Great news, so I only potentially need a Punto 75 fuel pump and pressure regulator to convert to a 75 engine, assuming that my Supersprint manifold is an early version. I've already sourced an engine so that's fantastic news.


A few further questions if you don't mind:

Would the 1108 MPi ECU be able to run the 75 engine prior to a remap?

Does anybody make a performance/race camshaft for the 75 engine please?

...and finally I also want to have some headwork done on the 75 engine which should hopefully bring some useful bhp gains, could anybody recommend a specialist tuning company that could perform this work?

Thanks again.

 

[ycming]

ermmm by any chance is the seicento red ? and he is a member of clubcento ?

Yes the ECU will get the car running. As for cam try here:

http://www.gazzella.cc/cart.php?target=category&action=view&category_id=650

They will all fit the fire engine :0.

Ming

 

[arc]

Punto 75 engine.
Punto 75 Throttle Body and Inlet.
Punto 75 injector wiring loom to splice in to the existing 1108 MPi injector wiring to use as batch injection.
3 Bar Fuel Pressure Regulator.
A Remap using the existing 1108 MPi ECU.

P75 engine, yes - but bottom end only. (more on this below)
P75 Throttle body and Inlet - no. Use the Seicento kit, if you want a larger TB then look into using a 1242cc 16v Mk1 punto Sporting TB.
P75 wiring etc - no. Use the Sei stuff.
3bar regulator. No, the Sei has it's regulation done in the tank. To fit an external reg you'll need to plumb in new returns and modify the pump.
A remap on the MPI ECU, ideally - yes.

The Sei MPI has a cam phase sensor. The ECU expects it to be there. The P75 top end lacks this. You could fit the cam cover and cam sprockets from the sei head into the p75 head - but you may as well leave it all and use the Sei head. You will need the lower pulleys and waterpump off the Sei as the belt pitch is different. You will need a MK2 Punto 1.2 8v timing belt.

 

[ycming]

Hmm ... don't the P75 head have bigger valves in them ?

Ming

 

[arc]

i dont think so, no. The P75 has bigger inlet valves (by 0.5mm) than the Punto55 and Punto 60 (pre may 1997, engine code 176.B4). But the Cinquencento and Seicento SPI def have the same size. I don't know for def with the MPI thouhg.

 

[ycming]

My mistake Arc, got confused with valve an ports:

craigb244 found the P75 to be better:

I noticed a few things with this head. the head on my 1.1 does not have the hatch effect on the outside. as far as i remember the ports on the 1.1 head are not cast as smooth as this P75 head. (took my a LOT longer to clean the ports on the 1.1 when i did it) but the biggest thing is the casting around the back fo the valve seats. on my 1.1 head the casting was really rough and you could feel the sharp edge of the steel seat.

https://www.fiatforum.com/blogs/craigb244/394-start.html

Ming

 

[Jube]

Thanks everyone for the extremely useful information and yes the car was from a top chap who's a Clubcento member.

Just to summarise the Punto 75 engine install then, I need to fit the following:

Punto 75 Bottom End.
Punto 75 Head using Seicento MPI Cam Cover / Cam Phase Sensor / Cam Pulleys OR Complete Seicento MPI Head with Punto 75 Camshaft installed.
Seicento MPI Throttle Body and Inlet.
Seicento MPI Lower Pulleys and Waterpump.
Install Seicento Knock Sensor on to the 75 block in a similar position to that found on the Seicento engine. (Taken from Fiat Forum Guide)
Manifold spacer or Early Supersprint.
MK2 Punto 1.2 8v timing belt
ECU Remap.

A couple of final questions please:

1) How does the 75 engine generate it's extra 15 bhp above and beyond the 1.2 8v Punto 60 engine? Is it just the higher lift cam and bigger inlet valves?

2) Is it easier to fit a Punto 60 engine using my Seicento MPI Head with a Punto 75 camshaft installed? This I believe is a straight swap except for using the Seicento Crank Sensor / Pressure Sensor and the Manifold clearance issue. Would this give me similar or the same bhp as a full Punto 75 engine conversion?

Thanks again for all of the advice.

 

[ycming]

The P75 is the easiest swap for the MPI centos.

Just use the FUll P75 engine with Seicento cam cover, then use all the pulley from the seicento.

If you are using all the pulley from a seicento, then i think you should use the cam belt for a seicento. (someone could confirm).

Ming

 

[arc]

1) How does the 75 engine generate it's extra 15 bhp above and beyond the 1.2 8v Punto 60 engine? Is it just the higher lift cam and bigger inlet valves?

It does it thanks to a slightly higher compression ratio, being MPI, a larger throttle body (38mm vs 32mm), warmer cam, bigger ports, better exhaust, more advanced ignition timing.

2) Is it easier to fit a Punto 60 engine using my Seicento MPI Head with a Punto 75 camshaft installed? This I believe is a straight swap except for using the Seicento Crank Sensor / Pressure Sensor and the Manifold clearance issue.Would this give me similar or the same bhp as a full Punto 75 engine conversion?

If you cannot find a P75 engine, then yes. If you get a Punto 60 engine from a car with the engine code 176.B4 then it should have the P75 cam (marked with 866) already.

As has been said though, the P75 has slightly larger ports on its head - so may be better off just getting that. I beleive the P75 bottom end also has oil jets for cooling the pistons - but i do not know for sure that the P60 does not have them.

Of course, you could look at a 1.4 8v instead for more power; https://www.fiatforum.com/cinquecento-seicento/221666-1-4-8-valve-project-seicento.html

 

[Jube]

Right I think I'm armed with enough conversion information now thanks but you have got me thinking after reading the 1.4 8v thread!

I've been looking on the Gazella and GSR Engineering websites for race camshafts which will suit the Punto 75 engine. Any recommendations on a suitable performance camshaft for a Track/Sprint car which is occasionally used on the road would be appreciated. (C&B 298/300 maybe?)

Has anybody got/had a similar specification engine to the one below? If so, what are their thoughts and what approximate horse power should you expect (or have people got) from the following spec please?

Punto 75 Bottom End.
Polished and ported Punto 75 Head.
C&B Race or GSR Camshaft.
Vernier Pulley.
Seicento MPI Inlet.
42mm 1.2 16v Throttle Body.
BMC CDA Induction Kit.
Supersprint 4-2-1 Manifold with 2" stainless custom exhaust inc. Decat.
Custom Remap.

Finally, what clutch would people recommend for the above spec please?

Cheers all.

 

[Todger182]

On my MPI sei I had:

P75 bottom end (now in classifieds, needs new rings and a hone but i'm pretty much throwing it away price wise)
GSR kit (looked like an exagerated whale *****)
866cam
40mm ported and polished throttle body
full stainless 50mm bore exhaust with race cat
NGK plugs
Magna KV85 leads (blue ones, and again for sale)
CSC 4 branch manifold
and obviously a remap

All those mods, and I had 80 BHP at the (14") wheels. (If your running 13" then you might expect a little more).

0-60 on mine was very quick, but onwards was sluggish, at the time I thought it was just struggling to feul and air. few weeks ago I find out that cylinder 3 was munching itself and the valve was about to fall apart completely.

Said goodbye to that engine and now in a dilema on a project.

Clutch wise I would keep to the standard, there isn't much point in upgrading unless your pulling silly power.

Thanks

 

[arc]

Has anybody got/had a similar specification engine to the one below? If so, what are their thoughts and what approximate horse power should you expect (or have people got) from the following spec please?

Punto 75 Bottom End.
Polished and ported Punto 75 Head.
C&B Race or GSR Camshaft.
Vernier Pulley.
Seicento MPI Inlet.
42mm 1.2 16v Throttle Body.
BMC CDA Induction Kit.
Supersprint 4-2-1 Manifold with 2" stainless custom exhaust inc. Decat.
Custom Remap.

Finally, what clutch would people recommend for the above spec please?

I had a very similar spec to that, i had a wee bit more headwork done (it was skimmed to the max markers and had multi angle valve seats cut), and only the stock p75 cam, still spi. My arse dyno put it around 85-90bhp. The car was very nippy, and could also breath quite well high up (it could hit the rev limiter in 5th).

Brooky was building a high revving engine based on my old engine (p75), his input would be good.

Clutch wise, if you are worried at all about it.. if you get a flywheel from a 1.4 16v, fit that, you can then use the clutch from a 1.4 16v stilo/punto/panda - it's bigger than the cento one, designed for more power and to move more weight.

 

[Jube]

Thanks yet again for the replies.

It's really nice to find another forum (I'm normally on the Fiat Coupe UK forum which is also excellent) which provides so much knowledge sharing.

My final thoughts on the thread topic are:

If I keep the Seicento standard clutch setup on a Punto 75 engine (I've got a lightened and balanced flywheel so I'm tempted to) which clutch release bearing do I use please? (75 or Seicento)

And my final question you'll probably be pleased to hear is:

Has anyone installed a wet NOS system on to a 1242 8v? If so how does the engine respond to say a 25 bhp increase? Do people think that this would have too much of a negative effect on the reliability?

Cheers,
Julian.

 

[arc]

the clutch on the P75 and seicento is identical as far as i know, use which ever bearing is new

I'm pretty sure RobW ran a NOS setup on his 1242 8v.

 

[Brooky]

Brooky was building a high revving engine based on my old engine (p75), his input would be good.

the engine is still all in bits. too many sports over last summer got in the way,
ill have to crack on with it.

lots of bits still half finished. skimmed the head, cleaned all the ports up and polished the combustion chambers. Very tempted to send the head to GC for a big valve jobby and some nice valve guides.
inlet manifold still miles away to getting the ITB's on.

Pissed off about loosing the CSC manifold on my other cinq when that got recoved and scrapped

 

[Jube]

Thanks again all for the excellent advice.

I'm pretty sure of the engine specification I'm going for now.

Cheers,
Julian.

 

[Brooky]

ps never order anything from gazzella, get Guy Croft to order you a cam in