zetec pistons and rods ?

[jack mc]

hi guys my names jack i have not long owned my fiesta mk 3 si. basicly i've been reading up on the zetec engines and a part from to straight replacement swaps with escorts i havn realy had much to do with these engines . ive read up that the newer black top zetecs used shorter pistons and longer rods to compared to the silver top is this true ? if so i was just wondering if you could use the black top pistons and silver top rods together to lower the C.R ? cheers

[Stu]

hi guys my names jack i have not long owned my fiesta mk 3 si. basicly i've been reading up on the zetec engines and a part from to straight replacement swaps with escorts i havn realy had much to do with these engines . ive read up that the newer black top zetecs used shorter pistons and longer rods to compared to the silver top is this true ? if so i was just wondering if you could use the black top pistons and silver top rods together to lower the C.R ? cheers

 

Hi, yes it's true. The black top engine had a superior 'slipper' style piston with a shorter compression height. This leads to less wear and a slightly more efficient engine.

 

However, the later pistons run a smaller Goodgeon pin than the early ones so i'm afraid your plan won't work.

 

Are you looking to turbocharge the 1.6 Zetec? If so I may have some suggestions from investigations some time ago.

[mykez69]

His fiesta has a 2 litre silvertop in. He is looking to buy another 2 litre to rebuild and supercharge.

[Stu]

In which case the most cost effective solution is to use pistons from a Vauxhall XE (or C20LET if you need a very low CR) on the original silver-top zetec rods. You'll need to bore the engine out and have the rods and pistons modified slightly but it's a tried and tested solution. Alternatively buy a set of cheap rods and pistons from America (although not that cheap anymore due to the value of the Pound). Edited April 9, 2010 by Stu

[jack mc]

In which case the most cost effective solution is to use pistons from a Vauxhall XE (or C20LET if you need a very low CR) on the original silver-top zetec rods. You'll need to bore the engine out and have the rods and pistons modified slightly but it's a tried and tested solution. Alternatively buy a set of cheap rods and pistons from America (although not that cheap anymore due to the value of the Pound).

 

well im actualy going to turbo it now rarther than superchage it i have had loads of expiriance with engine builing and what not but i am new to the zetec's. i can get most of the machineing done at work apart from block work as th block is to big for our machines. i only wont to run moderate boost say 14 ish psi so i was thinking maybe skim a small amount off the pistn crowns and use a thick head gasket ? .i will then fabricate an adapter plate to fit the rs turbo exhaust manifold and turbo. And i was plnning on useing the rs turbo ecu and i haven't got as far as thinking about the injector side of things although i would like to keep the zetec efi inlet manifold. do the galaxy 2.3's have bigger injectors that will fit or if not do you reckon i would get away with a adjustable boost sensitive fuel reg ? cheers

[Stu]

In which case the most cost effective solution is to use pistons from a Vauxhall XE (or C20LET if you need a very low CR) on the original silver-top zetec rods. You'll need to bore the engine out and have the rods and pistons modified slightly but it's a tried and tested solution. Alternatively buy a set of cheap rods and pistons from America (although not that cheap anymore due to the value of the Pound).

 

well im actualy going to turbo it now rarther than superchage it i have had loads of expiriance with engine builing and what not but i am new to the zetec's. i can get most of the machineing done at work apart from block work as th block is to big for our machines. i only wont to run moderate boost say 14 ish psi so i was thinking maybe skim a small amount off the pistn crowns and use a thick head gasket ? .i will then fabricate an adapter plate to fit the rs turbo exhaust manifold and turbo. And i was plnning on useing the rs turbo ecu and i haven't got as far as thinking about the injector side of things although i would like to keep the zetec efi inlet manifold. do the galaxy 2.3's have bigger injectors that will fit or if not do you reckon i would get away with a adjustable boost sensitive fuel reg ? cheers

 

There isn't really enough meat or strength in the OE pistons to do what you suggest above. I've done some testing with budget conversions (using multiple HG's and a spacer shim - see my zetec turbo guide) but it wouldn't really be adequate for 1 bar of boost on a 2L (which typically equates to approx 250bhp on a decent size turbo). You really want to change the pistons.

 

Which RS Turbo ECU are you talking about? If you mean the Fiesta stuff then sure you can use that, but it's not the cheapest or easiest management to get remapped for your spec and using some off the shelf (eg '195' chip) will only lead to disaster. I'd be looking at aftermarket management, Megasquirt being the cheapest really.

 

I'm not sure of the flow rate of the 2.3 injectors, but they certainly wouldn't be enough for 250bhp! The RS2000 ones flow more than the zetec, but again not enough for that power. I do sell a direct drop-in upgrade injector by Cosworth/Bosch which is good for up to 220bhp at the stock 2.7 bar fuel pressure, or up to 320bhp with a 4.5 bar regulator (I can supply these too).

[jack mc]

epic well like i say i've only had the car two weeks so next stage is buyin my self a new shed for the garden. then i will buy another 2.0ltr lump and take it from there. i've not realy looked into rst ecu but i just assumed that with it being turbo management it would be up to the job ? but will most lightly go for megasquirt as you say mate. but i will be getting a wide band lambda sensor and a/f ratio gauge befor i even consider putting the engine in to aviod disaster as much as possible and i realy dont like the sound of decomp plate and double headgasket. do you no exactly what needs to be done to the top end of the rod to fit let pistons ? and also do u no a place to get the pistons from for a reasonable price ? this will be a budget build as im not a millionair or i would just buy evo or something like that lol cheers for the help so far :-)

In which case the most cost effective solution is to use pistons from a Vauxhall XE (or C20LET if you need a very low CR) on the original silver-top zetec rods. You'll need to bore the engine out and have the rods and pistons modified slightly but it's a tried and tested solution. Alternatively buy a set of cheap rods and pistons from America (although not that cheap anymore due to the value of the Pound).

 

well im actualy going to turbo it now rarther than superchage it i have had loads of expiriance with engine builing and what not but i am new to the zetec's. i can get most of the machineing done at work apart from block work as th block is to big for our machines. i only wont to run moderate boost say 14 ish psi so i was thinking maybe skim a small amount off the pistn crowns and use a thick head gasket ? .i will then fabricate an adapter plate to fit the rs turbo exhaust manifold and turbo. And i was plnning on useing the rs turbo ecu and i haven't got as far as thinking about the injector side of things although i would like to keep the zetec efi inlet manifold. do the galaxy 2.3's have bigger injectors that will fit or if not do you reckon i would get away with a adjustable boost sensitive fuel reg ? cheers

 

There isn't really enough meat or strength in the OE pistons to do what you suggest above. I've done some testing with budget conversions (using multiple HG's and a spacer shim - see my zetec turbo guide) but it wouldn't really be adequate for 1 bar of boost on a 2L (which typically equates to approx 250bhp on a decent size turbo). You really want to change the pistons.

 

Which RS Turbo ECU are you talking about? If you mean the Fiesta stuff then sure you can use that, but it's not the cheapest or easiest management to get remapped for your spec and using some off the shelf (eg '195' chip) will only lead to disaster. I'd be looking at aftermarket management, Megasquirt being the cheapest really.

 

I'm not sure of the flow rate of the 2.3 injectors, but they certainly wouldn't be enough for 250bhp! The RS2000 ones flow more than the zetec, but again not enough for that power. I do sell a direct drop-in upgrade injector by Cosworth/Bosch which is good for up to 220bhp at the stock 2.7 bar fuel pressure, or up to 320bhp with a 4.5 bar regulator (I can supply these too).

[Stu]

No problem. Of course changing to a more suitable piston is superior to the other solution I proposed, but it's considerably more expensive (if you do it properly!). If you factor in £200-600 for a set of pistons new (depending on which ones you get exactly, XE or LET - you can buy used but factor in £60-100 for a new set of rings), plus say £120 for a bore+hone of the block, and then about £80-100 to fit the rods onto the pistons (small end of the rod has to be reamed out and then press-fitted to the GM pin), oh and also some machining to the piston skirt and inside of the piston to allow sufficient rod clearance (£60+) - all of a sudden it's not looking so cheap?

 

This conversion will cost you at least £3k if you do most of the work yourself, and quickly £5k+ if you have to involve professionals to do any installation or tuning. Mapping an engine isn't as simple as you may think, or from what 'experts' on some forums may have said (eg megasquirt forums).

 

I do supply a few parts with regards to zetec turbo conversions, but not the pistons you're after. I can do you a good deal on a set of forged pistons though and/or steel rods if you want to go the whole hog (probably only a few hundred quid more than going the GM piston route, once you take into account the machining required). This would give you a bottom end strong enough for in excess of 300bhp which leaves you open to expansion in the future.

 

Don't forget about the valve train - the stock valve springs aren't good enough for what you're proposing. I can supply a set of uprated valve springs that are good for approx. 320bhp @ 6000rpm - beyond that you'd need to look at a double valve spring conversion which I can also supply (you'd need to supply your head for modification).

 

I'm in the middle of re-writing my zetec turbo guide. The cheapie spec (spec A as it's originally called) is complete bar a few photos, and there are two other specs I need to write up yet. So keep an eye out for that

 

 

epic well like i say i've only had the car two weeks so next stage is buyin my self a new shed for the garden. then i will buy another 2.0ltr lump and take it from there. i've not realy looked into rst ecu but i just assumed that with it being turbo management it would be up to the job ? but will most lightly go for megasquirt as you say mate. but i will be getting a wide band lambda sensor and a/f ratio gauge befor i even consider putting the engine in to aviod disaster as much as possible and i realy dont like the sound of decomp plate and double headgasket. do you no exactly what needs to be done to the top end of the rod to fit let pistons ? and also do u no a place to get the pistons from for a reasonable price ? this will be a budget build as im not a millionair or i would just buy evo or something like that lol cheers for the help so far :-)

[jack mc]

ok well could i not use the 2.3 zetec head to lower the compression ? because if it has bigger pockets than the to litre head then this would make the uncompressed capasity larger and the the compressed pressure lower would it it ? i've proberly worded it wrong but i no what mean to say lol does any one no what the static c/r is and the dynamic c/r is ? and i should be able to get away with a mega squirt ecu and retard the timing slightly,adjust the cams to alter the dynamic c/r sligtly and run high octane fuel ? as i only wont to run low pressure and im not aiming for anything stupid also just wondering does the zetec tae well to a decat ? as i've bin told they run bettin with a cat ? cheers

[KNITERIDER]

only bit i can answer is the cat, but most on here have de catted and only a few say it was worse. to be honest its niether here nor there tho but a decat shouldnt do anything bad or at least iv heard no horror stories

[Stu]

ok well could i not use the 2.3 zetec head to lower the compression ? because if it has bigger pockets than the to litre head then this would make the uncompressed capasity larger and the the compressed pressure lower would it it ? i've proberly worded it wrong but i no what mean to say lol does any one no what the static c/r is and the dynamic c/r is ? and i should be able to get away with a mega squirt ecu and retard the timing slightly,adjust the cams to alter the dynamic c/r sligtly and run high octane fuel ? as i only wont to run low pressure and im not aiming for anything stupid also just wondering does the zetec tae well to a decat ? as i've bin told they run bettin with a cat ? cheers

 

There is no 2.3 zetec.

 

So you've gone from swapping rods, to skimming pistons and now onto bodging a n/a engine?

 

I'd find a good tuner and go solely by their advice as it looks like you're getting confused by lots of different sources of (mis)information on the internet.

[jack mc]

well no not realy its just theres that many different ways to lower the compression ratio and the rods was a simple qaustion ? as were the pistons plus i heard that people put the 2.3 heads on the 2.0 ltr engines to apparently make 2.1 so i fgured the only way it could make 2.1 is to have bigger volume pots in the head in witc case would lower the compression ratio and as for the de cat bit i was only asking because mine sounds like its decated but the caseings still there so not shore if previus owner shafted all the sh** out the inside of it

ok well could i not use the 2.3 zetec head to lower the compression ? because if it has bigger pockets than the to litre head then this would make the uncompressed capasity larger and the the compressed pressure lower would it it ? i've proberly worded it wrong but i no what mean to say lol does any one no what the static c/r is and the dynamic c/r is ? and i should be able to get away with a mega squirt ecu and retard the timing slightly,adjust the cams to alter the dynamic c/r sligtly and run high octane fuel ? as i only wont to run low pressure and im not aiming for anything stupid also just wondering does the zetec tae well to a decat ? as i've bin told they run bettin with a cat ? cheers

 

There is no 2.3 zetec.

 

So you've gone from swapping rods, to skimming pistons and now onto bodging a n/a engine?

 

I'd find a good tuner and go solely by their advice as it looks like you're getting confused by lots of different sources of (mis)information on the internet.

[Stu]

I'm not trying to crap on your idea, but again there is no 2.3 zetec. Be careful who you listen to, which is why I suggested you only deal with a single source of information (eg a tuner).

 

well no not realy its just theres that many different ways to lower the compression ratio and the rods was a simple qaustion ? as were the pistons plus i heard that people put the 2.3 heads on the 2.0 ltr engines to apparently make 2.1 so i fgured the only way it could make 2.1 is to have bigger volume pots in the head in witc case would lower the compression ratio and as for the de cat bit i was only asking because mine sounds like its decated but the caseings still there so not shore if previus owner shafted all the sh** out the inside of it

[jack mc]

well like a say mate thats why i came on here to be fair to ask qaustions and get propper true ansers from people who have experiance with the zetec engines i looked at some pics of the 2.3 engines and like you say there nothing a like think all im gonin to do is souce some decent second let pistons and fit them with new rings and then take it from there im allowing about a year for the build so it wont be rushed cheers for the help so far tho mate

I'm not trying to crap on your idea, but again there is no 2.3 zetec. Be careful who you listen to, which is why I suggested you only deal with a single source of information (eg a tuner).

 

well no not realy its just theres that many different ways to lower the compression ratio and the rods was a simple qaustion ? as were the pistons plus i heard that people put the 2.3 heads on the 2.0 ltr engines to apparently make 2.1 so i fgured the only way it could make 2.1 is to have bigger volume pots in the head in witc case would lower the compression ratio and as for the de cat bit i was only asking because mine sounds like its decated but the caseings still there so not shore if previus owner shafted all the sh** out the inside of it