Technical Exhaust/performance mods

[Stickman]

Hello all!

I'm interested in fitting a sports exhaust to my '99 Sei. I don't want to spend too much, within reason, but I'm willing to pay for a decent increase in power. I'm more interested in performance increase than sound - though I love a good exhaust note, the reason I want to do this is for a power increase more than anything else.

And also - can anyone think of other mods to increase power without tampering with the engine? Definitely not interested in turbocharging or block expansion, and I'm skeptical that chipping may harm my car or its fuel consumption (why would Fiat's CPU not be optimized?). I'm out of ideas.

Sorry for all the questions!!!

 

[GoBe]

Start with the basics, fresh plugs and decent HT leads.

Then get a proper induction kit along the lines of the GSR kit should do just fine, something like the K&N kit will generally make things worse until you get to the top end as it's just sucking in hot air.

As for the exhaust a Supersprint back box would be a nice start, it sounds a little sporty but couldn't be considered OTT and gives a reasonable gain.

And get your self a McKrich chip, it works & is fairly well proven, you see an engine map is a compromise & most mappings shift the compromises more towards power/torque output & thus economy, the main difference is that you'll find the engine really doesn't like low quality fuel but also the engine is less tolerant of problems.

If you don't mind getting your hands slightly dirty a Punto 75 '866' cam also gives you a bit more go.

 

[Stickman]

Thanks for an extremely helpful reply!

How's this for a 'box?

http://www.motorsportworld.co.uk/frame-detail.asp?PAGE=/supersprint-exhaust.htm

Price is about what I expected optimistically. Do you think this will make a noticable performance difference?

As for the K&N, I didn't choose it - the previous owner fitted it, and she clearly didn't read FF! Meanwhile, if I'm doing the exhaust I can't change the filter too, so I'm adding an extra cold air feed (possibly a third one too) to make sure that it gets as much cold air as possible.

What is the Punto 75 cam all about? How does this help?

Many thanks

 

[GoBe]

The P75 cam is a slightly hotter cam, think of it as a poor mans fast road cam. It helps the engine generate more power and torque but doesn't limit you to the high end of the rev counter.

 

[D|s]

sry to deviate from the topic but why are K&N induction kits that bad? i thought they where pretty renound :S

 

[clawliger]

from what ive been told its not that K&N is bad. the filters are of a very high quality. its just the positioning. it sits on top of the TB and thus directly over the bulk of the engine. and seing as heat rises. the filter sucks in the hot air. and also becuase hot air containts less oxygen then cold air. performance gains are lost. low oxygen = low performance.

the thing witht he GSR kits is that the filter is positioned just below where the ECU is in kind of like a ready made gap for a filter. this brings it away from the heat. also the silicone hosing used is more heat resistant than the nomral plastic filter and as it moves along towards the TB the hose reduces in size therefore forcing more air through a smaller gap.#

say if you ahd the K&N filter itself on an extended reducing peice of silicone hosing like the GSR kit. that should work well.
hope that helps.

 

[eMz]

I've currently just got a K&N Aifilter alone in my engine bay and looking to get an induction kit. I've been advised not to get a K&N induction kit simply because of where it sits. (e.g. sucking in hot air from the engine)

Apart from the GSR kits are there any other good kits about?

 

[GoBe]

from what ive been told its not that K&N is bad. the filters are of a very high quality. its just the positioning. it sits on top of the TB and thus directly over the bulk of the engine.

:yeahthat:
Basically the K&N filter is good it's just the location sucks. While the filter lets more air volume in, the problem is due to its location once the engine is warmed up the air mass going into the engine is reduced until high up in the rev range compared to the stock air filter. I've seen an experiment with a piece of drain pipe putting the K&N filter over the top of the gearbox & the result was impressive.

 

[GoBe]

I've currently just got a K&N Aifilter alone in my engine bay and looking to get an induction kit. I've been advised not to get a K&N induction kit simply because of where it sits. (e.g. sucking in hot air from the engine)

Apart from the GSR kits are there any other good kits about?

A piece of drain pipe, 2 90 degree elbows & a little ingenuity goes a long way.

 

[eMz]

Smart one ain't ya.

 

[Italian Coke Can]

The supersprint exhaust gives a bit more mid range and a touch deeper sound.

It would be behind the tricker throttle / chip / induction kit on my lists of mods for bang-per-buck. (but ahead of the cam)

 

[Brooky]

The P75 cam, think of it as a poor mans fast road cam.

Does that make a C&B 280cam a rich mans cam????

 

[Stickman]

A piece of drain pipe, 2 90 degree elbows & a little ingenuity goes a long way.

How so? Moving the filter itself or merely directing more cold air through the chin spoiler down the pipe?

 

[GoBe]

Brooky, something like, being about 10x the cost of a P75 cam!

stickman, move the whole filter. It's not the best solution but with a little thought it can be made to work.

 

[blu73]

also a few tb's that will fit, my old sei had a tb off a punto 60 which is a 32mm one rather than the 30mm as on the cento's as standard (i think though that not all punot 60's have 32mm ones some have 30mm ones the same as the cento's so take a ruler or tape measure). They don't make a huge difference and don't expect the same results as a tricker tb (40mm) but you can pick one up for next to nothing at a scrappies and its a straight bolt for bolt swap.
I believe a punto 75 tb can be made to fit as well which is 36mm iirc but not a bolt to bolt swap and some people have modified some peugeot tb's but you'd have to search to find that out.

Reckon it was well worth the £15 i paid for it

 

[balidey]

i think though that not all punot 60's have 32mm ones some have 30mm ones the same as the cento's so take a ruler or tape measure

If (like me) you forget to take a tape measure to the scrappy, the size is dot stamped on the back of the lower part of the throttle body.

 

[blu73]

think the colour of the plastic spacer under it has something to do with the size as well (you'll need that spacer btw)

 

[balidey]

think the colour of the plastic spacer under it has something to do with the size as well (you'll need that spacer btw)

Yes you need the matching spacer. No, the colour is not size specific. I have two dark red ones, one is 30mm, the other 32mm.

 

[arseofbox]

And also - can anyone think of other mods to increase power without tampering with the engine? Definitely not interested in turbocharging or block expansion, and I'm skeptical that chipping may harm my car or its fuel consumption (why would Fiat's CPU not be optimized?). I'm out of ideas

It is optimised. For maximum fuel efficiency. It means the thermal efficiency and maximum power are strangled as a result.

This is why tuning an engine for power results in more fuel usage over standard...

 

[GoBe]

It is optimised. For maximum fuel efficiency. It means the thermal efficiency and maximum power are strangled as a result.

This falls flat on its face as most of the time for petrol engines you actually get better fuel economy post-mapping than stock. This is the reverse from what you say happens.