Engine Conversion Options

[c_r_thomson 0]

Currently toying with replacing my newly blown head gasket!

 

Once i've got the head off i was thinking of either getting some head work done to increase performance or just calling it quits and changing the engine!

 

The engine i've got in at the mo is a 1991 1.9 8v with 80k on it.

 

What would've caused my head gasket to go? can my engine still be trusted? What conversion options do i have? and is the head work really that beneficial?

 

As you can tell i'm really undecided about what is best so all advice and opinions are welcome

 

Thanks guys, Craig

[veloce200 3]

and is the head work really that beneficial?

 

cylinder head is the single most important component on the engine to producing good power. Every other bit of the Pug 1.9 8v is more than up to the job so you are right to focus on the head. You will probably want to replace the seals at the bottom of the liners if they have been disturbed or if the symptom of your gasket failure was water mixing with oil.

[Jonmurgie 2]

Head work is good (if done correctly) but on the pugs they respond best to carbs/throttle bodies as they do suffer with the standard inlet setup.

 

Who do you have in mind for the headwork?

 

With regard to why the gasket has gone, you kind of need to get the head off first and see WHERE it's gone and then you can start working out why

[Guest Megster]

I took a healthy 1.9 8v engine and added a secondhand Skip Brown "S" spec head, secondhand twin 45 Dellortos and a secondhand group n exhaust (Thank God for Ebay). My car now makes 154bhp at the fly wheel - 25 to 30 bhp up on claimed standard power when new. Total cost for doing all this was close to a grand including all parts and dyno set up.

 

I think that I've found all the "cheap" power now - but if anyone can suggest anything else...

 

There are 200 bhp normally asprirated 8vs out there, but it takes serious money and the talents of respected engine builders (Mark Shillaber, Longman, SBC, etc) to get that figure. I've raced against some of these cars (we aren't allowed Mi16 conversions in Road Modifeild Sprint Class) and you can certainly hear and see where the money went!

 

AJ

Edited August 16, 2006 by Megster

[c_r_thomson 0]

Was looking at Ported standard valve head chemical clean, skim, 3 angle seats from puma racing

[veloce200 3]

but it takes serious money and the talents of respected engine builders (Mark Shillaber, Longman, SBC, etc) to get that figure.

 

that's it in a nutshell. Use a reputed source and a modified head alone will make a big difference to an otherwise std 1.9. I think I am right in saying Grp A cars were 160 with the injection system (albeit probably with a few tweeks to the ECU to cope with the cam). I've always modded the head first. Did a mini one years ago and we took 3 seconds out of the 0-60 time with just porting and skimming but then it's easy to get 3 seconds when the std time was 17....!!! (and anyone can mod a mini head with Vizards book!)

Edited August 16, 2006 by veloce200

[Rob_the_Sparky 9]

Was looking at Ported standard valve head chemical clean, skim, 3 angle seats from puma racing

 

Good luck, his waiting list is about the longest you will ever come across.

 

wrt what makes an HG fail it is usually corrosion of the head where it seals to the piston plus engine overheating.

 

wrt tuning. Head work on an 8v is a good way to get more power but if you are looking to spend that sort of money than get a 16v. They are 160bhp stock with potential for a LOT more once you start tuning them and as they are stock they do not need expensive engine management. For you info I also run a tuned 8v but I wouldn't take this route again, it costs far too much for the limited gains available. Start with an engine with potential rather than one that is already near its limit.

 

Rob

 

P.S. A head skim is very cheap and will quickly get the car back on the road...

[c_r_thomson 0]

Good luck, his waiting list is about the longest you will ever come across.

 

wrt what makes an HG fail it is usually corrosion of the head where it seals to the piston plus engine overheating.

 

wrt tuning. Head work on an 8v is a good way to get more power but if you are looking to spend that sort of money than get a 16v. They are 160bhp stock with potential for a LOT more once you start tuning them and as they are stock they do not need expensive engine management. For you info I also run a tuned 8v but I wouldn't take this route again, it costs far too much for the limited gains available. Start with an engine with potential rather than one that is already near its limit.

 

Rob

 

P.S. A head skim is very cheap and will quickly get the car back on the road...

 

Cheers for the advice Rob, I'm going to try sourcing an engine and see about fitting it myself

[Rob_the_Sparky 9]

A straight 8v engine swap isn't hard with the right tools and being careful to note wire locations before taking it apart. Have done a couple myself (one in a weekend with some help on the second day)

 

A 16v engine swap needs a few wiring and rad position mods but is a well trodded route, do a few searches on here and you will find a wealth of information on the subject.

 

Rob

[yorkdave 1]

for me i would skim the head and get her running again then buy an mi. i put one in mine with bike carbs and piper reground cams and she is so fast! they just get above 5k and just take off! and like someone else says you start off with the power of a grands worth of 8valve tuning.