Tuning Long shot but - 8v to 16v conversion?

[imapctuk]

So, is it possible to convert an 8v SOHC engine to a 16v DOHC?
Like how much work involved, what things would i need to swap etc.
I know that it would involve a lot of work and i'm just generally wondering if it would be possible.
I understand it would be easier to buy a sporting but thats not really what i'm looking to do.
So what are your opinions?

inb4 "Don't bother, buy a sporting" and "theres no point"

 

[bredsticz]

Just been covered recently, need to change all of the top half on the engine, loom, ecu etc. Very very expensive but possible!

 

[imapctuk]

You got a link?
Cheers bredsticz

 

[bredsticz]

https://www.fiatforum.com/punto/236467-punto-mk2-1-2-8v-1-2-16v-conversion.html

Here ya go. Again it's just people saying don't bother and teaching me a thing or 2 about 8v and 16v engines

 

[imapctuk]

After reading that its made me ralise that its definatly going to require a lot more effot than i thought. I was hoping it would be as simple as swapping the head and the cams, but then again i am naive.
Anyway, a similar question - what sort of mods would allow a similar performance increase?
I understand there are very limited tuning capabilites in the 8v engine, i'd just like a bit more pull.
Thanks

 

[bredsticz]

Can't get that much out of an 8v, but:
GSR Induction (focus one doesn't really give anymore power)
De-cat, (or sport cat)
Keep well serviced!

Not much more you can do for power really

 

[imapctuk]

Haha just as i thought. Yeah the Focus one doesn't particularly do anything other than making it sound nice. But it sounds nice and doesn't go anywhere hahah. Its a bit embarasing when people are looking at me and i put my foot down
What sort of sport cat would you recommend? Isn't a de-cat illegal?
And i make sure to keep it well serviced, along with cleaning it almost twice a week haha.

 

[bredsticz]

Could do with cleaning mine!
De0cat isn't illegal but chances are it will fail MOT without it as emisions will be high.
Can keep original cat and change it over for MOTs.

Don't know any sports cats so can't help you there I'm afraid

 

[imapctuk]

Haha i'm obsessed with cleaning mine.
I'm guessing i need a pipe instead of a cat. Does anyone know what sort of pipe? Diameter?
But yeah that seems like an easy solution for a bit more power, as long as its not illegal

Another question (sorry!) - i read somewhere that certain early Punto ECU's can't be re-mapped. Is this true? Mines a 2001 MIA

 

[bredsticz]

A few people on here re-map ECUs. Would have to find out who they are and speak to them about it really! I think you get more benefit of you have done mods to the car and get it re-mapped to work better with the modification.

I do know what you mean about being embarassed when you put your foot down! Like the mini that left me in it's dust this evening

 

[imapctuk]

Hahah! That's unlucky. My problem is the hill near mine. I have to put my foot down a fair bit to even get up it which makes my car growl loudly and everyone is looking at me struggling.

I just read that a de cat could make the car lose mid rang torque. However i suppose a bit of pipe is worth a shot. If it does lower performance, its not exactly gonna break the bank.
Cheers for your help bredsticz, much obliged!

 

[custard]

as a general rule of thumb
when it comes to bigger mods like engine swaps/turbos etc
theres no point if you can buy the same model or same power in the model range already

 

[DaveMcT]

If you want more power fit a more powerful engine and box. Good old FIat will have fixed all the problems (unless its an HGT of course).

On the valves subject poppet valves flow around the circumference so logically a larger valve flows more gas. But a pair of smaller valves flow even more - do the sums to check it out. Smaller valves also contact more metal on the rims so get better heat conduction when they are closed.

The snags are that large valves can flow lots of air at full revs, but with such large holes, the air flows too slowly at low revs so the cylinders dont fill so well. Large valves are good for power but at the expense of drive-ability and economy in the mid range. The new Fiat Multi Air uses variable inlet valve timing to solve part of this problem.

The motor makers only went to 16 valves because they were required to fit exhaust catalysts. These need a hot exhaust gas and the older large single valves couldnt cope. So they fitted a pair of smaller valves that would cool better when closed.

Some went to three valves (1 In + 2 Exh), but because more is better in marketing most went to 4 valves (16 on a 4 banger engine). Most dont flow much better than the earlier 8Vs and they are heavier and more costly to service, but they do suit the dreaded cat.

8 valve engines dont have to be slow and weak. My bike although not powerful in bike terms is no slouch. Standard spec is -
892cc
Power 89.5 bhp @ 8350 rpm (red lines at 9000)
Torque 83.4Nm (61.5ft lbs) at 7000 rpm

With a stronger crank, forged pistons, flowed head, specials cams etc, a Fiat 1200 8V should be tuneable to 120+ bhp and by the way the bike is fed by carburettors.

 

[imapctuk]

I'm guessing with the things you just listed that it will also require a remap to work correctly. I've just had a look on the gsr website and it looks like they do the mods you just listed but I'm guessing they don't live anywhere near me. What sort of places should I look out for that can Skim the head etc? Will a normal garage do it?
Thanks fir your replies, they've been most helpful

 

[Moosey]

I'm guessing with the things you just listed that it will also require a remap to work correctly. I've just had a look on the gsr website and it looks like they do the mods you just listed but I'm guessing they don't live anywhere near me. What sort of places should I look out for that can Skim the head etc? Will a normal garage do it?
Thanks fir your replies, they've been most helpful

Where are you located? Heads have to go to a machine shop to be skimmed.

 

[DaveMcT]

The head should only be skimmed if its warped.

If you want it gas flowed ported and chamber balanced either buy an engine tuning book (e,g, anything by David Vizard) and a spare head(s) to practice on or spend £££s on a professionally ported head.

 

[alexbpl]

I think the unfortunate realism is that a 1.2 at the end of the day will only be as fast as a de-cat pipe and an induction kit without spending huge money. Engine tuning is expensive and the benefits are small unless you spend a lot.

The 8v engine though, is arguably easier to turbo than the 16v and would probably respond well to a half decent DIY turbo kit i.e 5th injector setup, uno turbo intercooler, simple manifold pressure switch without standalone fuelling.

As for the head conversion.

It is possible and could be done for a lot less than you'd think.

I got myself a sporting loom for £20, and I know where theres a good engine for £150. So thats half your problems sorted already!

It would however require finding a (preferably) complete 1.2 16v sporting engine...which begs the question - why not just fit the whole thing?

 

[imapctuk]

Where are you located? Heads have to go to a machine shop to be skimmed.

I live in Lytham St. Annes, just below Blackpool in Lancashire.

The head should only be skimmed if its warped.

If you want it gas flowed ported and chamber balanced either buy an engine tuning book (e,g, anything by David Vizard) and a spare head(s) to practice on or spend £££s on a professionally ported head.

What sort of tools would i need to do this myself?

I think the unfortunate realism is that a 1.2 at the end of the day will only be as fast as a de-cat pipe and an induction kit without spending huge money. Engine tuning is expensive and the benefits are small unless you spend a lot.

The 8v engine though, is arguably easier to turbo than the 16v and would probably respond well to a half decent DIY turbo kit i.e 5th injector setup, uno turbo intercooler, simple manifold pressure switch without standalone fuelling.

As for the head conversion.

It is possible and could be done for a lot less than you'd think.

I got myself a sporting loom for £20, and I know where theres a good engine for £150. So thats half your problems sorted already!

It would however require finding a (preferably) complete 1.2 16v sporting engine...which begs the question - why not just fit the whole thing?

I heard that a turbo conversion requires a lot of tweeking using specalist equipment?
Also i would love to do an engine swap but wheres the fun in that?! I was also kind of hoping that it wouldn't effect my insurance as much as a full swap, but knowing me i'm going to be wrong haha.

 

[Moosey]

I live in Lytham St. Annes, just below Blackpool in Lancashire.

This looks to be the closest machine shop to you. Description is vague though.

http://maps.google.co.uk/maps/place...cd=8&cad=src:pplink&ei=6H3vS6m0JtS8jAecouimDw

 

[alexbpl]

Funnily enough I live in Blackpool too!

We live quite close to the 'Road & Rally Centre' in Layton, on Hoo Hill industrial estate.

They are the mutts nutts in machining work. I got my flywheel lightened there for £45 which isn't bad.

Not sure why you would wan't your head skimming though. Unless you were going to fit a de-compression plate for a turbo kit, the cost of skimming a head would probably get you a decent second-hand 1242 16v engine!

I say you swap the entire engine as it is way less work, with a lot less to go wrong.