Engine Conversion

[Gareth 0]

i'm looking into doing a 2.0L 8v G60 engine conversion for my G60 and would like sum advice about what block, pistons, rods and crank to use??

i like the sound of a longer stroke as this is soppozed to give better torque

what sort of compression ratio would i expect or look for?? keep original 8.0:1??

keep my ECU or get another??

im also thinking bout porting and polish the head and getting the inlet man and outlet man port matched.

i read that my original exhuast man is a good one, but can i get better from another VW??.

intrested in 4-2-1 type exhaust.

also inlet man.. is there a better one from another vw??

a cam will be on the hope i can afford it list. b4 i had the funds for such a conversion i was going to get a mild cam from schrick, but now.. hehe :) so should i still use that sort of schrick cam??

the gearbox will get sorted too and maybe a 6th gear but i know where to get that done.

 

one of my main concerns is will all the internal componants handle the torque that will be produced from this type of conversion. i want to take my time and re-search this properly b4 i start buying anything but im looking forward to it. but unfortunately my budgit will have its own say with regards to the finished product.

ive seen engines for sale from proformance parts suppliers/specialists and could probley just buy one but thats not the route i want to take.

 

ive looked at what Henny has done to his car and that really interests me but henny is far cleverer than me and knows what crank and pistons to use. i think henny's motor has been very well researched and exicuted, so how can i ignore henny's brilliance? i can't and must concider the same path, i take my hat off and bow down to you henny :lol: . but as i said before im without the Knowledge.

 

anyway any advice and infomation welcome.... and thanx for reading

[CoxyLaad 0]

over to you henny

[stevemac 0]

A lot of Henny's engine work was done by John Mitchell (JMR Racing) 16vg60 on the forum. Maybe worth sending him a PM.

[beavis 0]

The main factors are what type of charicteristic do you want the engine to have and what are you mainly going to be using the car for. A daily driver you are going to want to keep maximum drivabiity in all conditions keeping 100% reiabiity. If your building a all out thrash wagon you can go balls out.

[Henny 0]

'lo! 8)

 

Firstly, when I started my project, I knew very little about the G60 engine... I learnt most of what I now know from on here and research into engines in general... 8) There's no reason anyone with a reasonable technical ability can't do exactly the same as I did... At the end of the day I bought the bottom end as a package from John (16VG60) so initially I had no idea what pistons, crank, compression ratio, stroke or bore I was going to end up with... I've since learnt pretty much exactly what is in there and have been MORE than happy with the results... 8)

 

As Beavis says, it's important to work out exactly what it is that you want your engine to be for... Have a flick through my members gallery (click on the J-DUB link in the sig below! ;) ) and you'll get some pretty good ideas of how I went about my conversion... :) It's also VERY important to have a chat with as many different people offering, or owning, engine conversions to gauge their knowledge and the reasoning behind their conversions... After Inters last year, I'd already written off 3 of the "off the shelf" conversions just due to attitude and lack of information... Don't expect people to tell you exactly what's going to be in any bottom end you end up with... at the end of the day, that's their little secret and research which they're making the money on, but you should be able to get out of them exact CCs, C/R and probably if the pistons are cast, turned or forged... 8)

 

It's true (to a point) that a longer stroke will give better torque, however you also loose some of the revvy-ness of the engine, so you have to be VERY careful not to over-do stroke at the expense of Bore... Some of the "off the shelf" 2.0 conversions are based on 2.0 Van engines which, IMHO, are not suitable for a nice revvy supercharged sports engine... My engine's an 83mm overbored Rallye block with a different crank in it and custom machined Mahle pistons which has then been fully blue-printed and balanced to give 1940cc and 8.5:1 C/R. The cam is a standard G60 cam and EVERYTHING which has gas going through it has been ported, port matched and flowed which, when coupled up with the Golf G60 intercooler gives rather a nice package! ;) 8)

 

The standard G60 injection and ignition (Digifant) system is pretty good... changing the injectors, fuel pressure regulator and chip will allow some pretty major modifications to be done without exceeding the ECU's capabilities.... you will have to get the chip custom written though, as your engine will most likely be a one-off and will need it's own map creating on a rolling road, so keep a good 3 or 4 hundred quid spare for this... 8)

 

Gearbox wise, I looked into quite a few places and eventually went with Stealth Racing 'cos I'd not heard a single negative comment about them and Vince is recognised as a God of VW gearboxes! :D Again, what you do to it depends on what you want out of the car... I considered quite a few things for my box, but after talking to Vince, I realised I was actually quite happy with the gearbox as a whole, I just felt that 2nd gear was WAY too short and it needed an LSD... so we put in a Quaife and a VR6 1st and 2nd gear and now I'm a happy bunny! :lol:

 

Have a think about what you want out of the car... Give some people a call and have a chat with them to see what they say and the routes they mention to get your car to where you want it to be, then sit and weigh up your options... 8)

 

Oh, and don't neglect your brakes and suspension... there's no point in having a nice fast engine if you end up wrapping the car around something (or someone) else at the first corner you come to due to crap brakes and handling! :|

 

Good luck! 8)

[Gareth 0]

beavis im looking for a daily driver with 100% reliability.

 

Henny ive taken everything that u said onboard and yes i will chat 2 as many ppl offering or owning engine conversions.

also thank u for the stroke/bore info and i'll be careful not to over do stroke.

ive heard that the transporter block can do the job but is not suited to forced induction so if its the same as u mentioned then i agree with u.

ok so i know what block, i'd be guessing but might know what crank as ive read another 83mm bore conversion useing another VW crank but as the pistons are custom then i dont know about them. i dont really want 2 use forged pistons as i read that there is more cold tolerance as they expand more with heat thus using more oil and (plz put me straight if i'm wrong about this) IMO would reduce the life of the bores, but cast ones might not be suited to the type of torque that will be produced so i guess i need to look into this.

 

thanx for telling me to keep aside money for the mapping of the chip as i did not think that it might cost that much:)

yes my gearbox would go to stealth and prob get the longer 2nd too, with the power output of this type of conversion IMO the quaife is a must but my budgit will have its say.

Brakes and suspension are also a must IMO so im with u all the way with that 1.

but with regards to suspension and the possible weight increase the engine might have, would i require a different setup?? or is it ok to use koni TA with H&R springs for a 91 G60??, this might sound like a daft Q but IMHO its better to look stupid than to get it wrong.

 

i didnt post the size of the crank im thinking of as i dont wanna upset any1 because as u said, and quote "at the end of the day, that's their little secret and research which they're making the money on". but is it possible for me to PM u the size of the crank im thinking of and car its from and you to tell me if im right or wrong. i don't expect this from u henny but i had to ask.

 

thanx to everyone for your time.

[Henny 0]

I honestly don't know what the crank is out of still... I've a good idea, but I respect John enough not to dig about too much as it's his little brain child and I know he spent lots of time researching it... The transporter block conversion is the one I was on about avoiding... I've mentioned it in my gallery thread and what my opinions of it are... ;)

 

If you get a GOOD set of pistons, it shouldn't matter much if they are cast or forged... mine are Mahle cast pistons which have been modified to fit the application properly... John must have spent a good while researching these pistons, as they took one hell of a hammering when a bolt got sucked into my engine, but there's no structural damage to the piston (had it X-rayed) which speaks wonders for them! I only decided to replace the whole set as I intend to USE this car hard and so don't want to risk a possible BIG failure when I can afford both the time and cash to make sure there's no compromises on this re-rebuild! 8)

 

The only daft/stupid question is the one you don't ask but wonder about... 8) The difference in engine weight is almost zero... I'd had my suspension corner-weighted before I did the rebuild, and got it checked out afterwards and there was almost NO difference! :) The Koni/H&R kit should do you nicely... I'm running on cheapo supersport coilovers 'cos they satisfied what I wanted at the time... I'll probably change 'em next summer when I save up a little money and get something a little nicer and probably start messing with anti-roll bars and the like at the same time! ;) 8)

 

IMHO, good people to talk to about the engine are: John (16VG60), Darren (G-man) and Vince at stealth.... The guys over at C&R are also worth chatting to about 2.0 conversions as they have several interesting upgrades available for the G60 block... 8)

 

Good luck! 8)

[Gareth 0]

ok thanx for all your help and advice its helped me sooo much....

i respect that John has put lots of time into researching the componants needed and at the end of the day if my only option is 2 buy the bottom end compleate then i probley will do that. i guess that my fear is i run out of money b4 its complete :cry: and im not even sure if sourceing the parts induvidually would save me money, i guess i just assumed that to be the case.

anyway i know i must get prices and then work out what i can n cant do.

 

Thanx to every1 again

 

the research continues 8)

[Henny 0]

8) 8) Keep us informed! 8) 8)

[beavis 0]

"Gareth. i dont really want 2 use forged pistons as i read that there is more cold tolerance as they expand more with heat thus using more oil and (plz put me straight if i'm wrong about this) IMO would reduce the life of the bores, but cast ones might not be suited to the type of torque that will be produced so i guess i need to look into this..

 

thanx to everyone for your time.

 

The main priority is to get a piston that is suited to the application i.e. a piston that is designed for use in a forced induction engine regardless of the process from which it has been manufatured. A forced induction piston has a lot thicker crown to absorb head in a more uniform fashion and beefier suiterbly spaced piston rings to cope with the extra stress running boost though a motor exerts.

There are good /bad forged and cast pistons. Generally forged pistons are tougher than cast, but a poorly made forged piston will be weaker than a well made cast piston with no blow holes in the casting.

We use forged pistons in our rebuilds, i'm not saying they are better than a well made forged piston, but in our opinion we like to use the best avalible to us. Also the british comapny we use, Accralite, make up small batch runs of a specific piston to our design requrements which is not as easy to comission with generally 'mass production ' cast items.

It is possible to buy off the shelf cast items and get them modifyed, but there is a lot of design that goes into a piston with regards uniform expantion, by removing material to alter compression ratio or add valve clearence can potentially drastically alter the way the piston was originaly designed to expand. Therefore we start with a fresh unit and get it designed from scratch to avoid any problems.

Forged pistons do have a greater bore/piston clerance when cold as forged units do expand more than cast items, but within the time it take the oil to come up to tempreture the units have expanded to the same tollerences that a traditional cast item will have when warm. The reason why forged items can get a bad name is basically from a poorly built engine when engine builders add far to much tollerance for expantion into the block as they incorrectly measure the cold forged piston and add tollerance onto tollerance which equtes to far far to much clerence between bore/piston. You then get excessive 'blow by' past the rings that leads to excessive crank case pressure and yes more consumption of oil as the oil scraper rings cannot do their job efficently. We have set tollerences and all the expantion is allowed for in the tollerance of the pistons during manufature so this error is never a worry.

Regardless of cast or forged, no piston is indestructable. If a engine is poorly set up or the right components are not used in relation to each other then both a forged or cast piston will fail, a forged piston will just fail at a later point. It is essential that fueling and cam profiles are adjusted to whatever spec you end up building your bottom end to.

On the same note, make sure when playing with cranks/rods if you do go down the restroking route is that you use a rod that is up to the job. Normally aspirated rods are generally a skinnier construction than a comarative forced induction item and will not withstand the torque of a blown engine. The same goes for gudgen pin diameter, normally aspirated items use a thinner pin generaly which will fail in a forced induction motor.

It is possible to build a daily driver, that sounds the nuts, gives the goods, is 100% reliable within your budget, just do your sums and investigate hard. :lol:

[Supercharged 2]

beavis, Thats the longest post you've ever made! - Some good info there :wink:

[beavis 0]

LOL.. I look vacent most of the time and have difficulty getting a sentance out at shows after the bottle of JD's the night before, but there is some useful information in the depth of mi head.

[W3RKD 0]

yep steve has a LOT of very valuable info locked away in that head of his u just need to pry it out usally jack daniels helps soften him up. :lol:

[Gareth 0]

beavis thanx for that superb infomation, :) :)

 

:nuts: My name in jonny five ....i need more input :nuts:

 

seriously thanx to everyone for helping :)

[Gareth 0]

ok so ive done some more re-search and would like to ask henny?? what was the reason for useing the 1H block?? was it purely because your PG block was no good (damaged) or that the 1H block can be bored more than the PG block??..... the reason i ask is if u have a 1940cc engine useing a 83mm bore then my figures just dont add up and im confused. because im trying 2 get basically the same bottom end as you then i need 2 find the right size crank and pistons.

 

Formula for cc: Pi / 4 x (bore^2) x stroke x the amount of bores (4 in this case).

 

Key:

Pi = (pie), 3.1415927

 

so: 3.1415927 / 4 = 0.7853982

 

0.7853982 x (bore^2) x stroke x 4 =

 

by the way i know that the bore and stroke are measured in mm but for the calculation it must be converted to cm.

the closest i can get to 1940cc is 1937cc (rounded up) but thats not useing a 83mm bore. now as u can see i havent mentioned the size of bore and stroke that i used in my calculation to get 1937cc as im not wanting to get anyones back up..... but maybe if we could chat on the phone or summit then i'll give u the figures im using.

i have tryed many diffrent bore and stroke combinations even useing the original stroke and as i said the closest i get is 1937cc

 

i hope that i have not affended any1, as that is not my aim. i just want to build a reliable engine and need to know everything b4 i commit to buying anything :)

[h100vw 0]

Henny isn't using a std crank. AFAIK.

It might be a std one from another dub but with the money he has spent that might be wrong too.

Gavin

[Henny 0]

The 1H block was used 'cos it was kicking around at Johns workshop and mine was found to be too far gone to be re-used! It's basically the same block as the PG so there's no real differences except it has slightly better water and oilways and uses larger head bolts... John would normally have used the PG block for this conversion and was slightly suprised that the head bolts were different too! 8)

 

You'd have to ask John what the crank is... as I said, I still don't know for sure and don't want to give you any wrong answers which could screw up your new engine by not being upto spec... I'll also guarantee that you won't just guess what the pistons are, as they're not a direct fit and needed some machining work doing on 'em to make 'em fit... ;) Nothing too severe, just a couple of little tweaks... 8) They are WELL upto the job though, and it must have taken John a LONG while to find 'em! 8)

 

Now that mine's back on the road, I can't believe just how much better it is... She's now got just under 100 miles on her since the little incident with the random bolt being sucked into the engine and she pulls like a freight train and seems to want to rev like a jet engine! 8) It's soooooo hard trying to keep her to a repectable level while I bed the new bits in! :|

 

You REALLY need to talk to John if you're serious about trying to get something similar to my engine... He's the only one who knows exactly what's in my engine with regards to the crank and pistons... I've sworn that I won't tell a soul what the pistons are as he did me a HUGE favour getting hold of the replacement ones when that bolt managed to get sucked in and damage one of 'em... 8)

 

Oh, and you've got that forumla slightly wrong... It's not BORE, it's RADIUS that you need to square to work out your engine specs... ;)

 

Formula for engine CC = No. of cylinders x (Pi x (piston radius in cm)^2 x (stroke in cm) )

 

Given that we all know that the engine is 1940cc and the bore is 83mm, it's not difficult to work out that each cylinder has a volume of 485cc... 8)

Bore = 8.3cm therefore piston area in cm^2 = Pi x (Radius^2) = 54.08cm^2

Therefore stroke = 485/54.08 = 8.97cm (2dp)

[Gareth 0]

Oh, and you've got that forumla slightly wrong... It's not BORE, it's RADIUS that you need to square to work out your engine specs... ;)

 

Formula for engine CC = No. of cylinders x (Pi x (piston radius in cm)^2 x (stroke in cm) )

 

Given that we all know that the engine is 1940cc and the bore is 83mm, it's not difficult to work out that each cylinder has a volume of 485cc... 8)

Bore = 8.3cm therefore piston area in cm^2 = Pi x (Radius^2) = 17.225cm^2

Therefore stroke = 485/17.225 = 28.15cm (2dp)

 

The book im reading on the subject has this formula for displacement: Pi/4 x bore^2 x stroke x 4.

 

i'm going to give figures here so that there is no confusion

this is my working out:

first, Pi divided by 4 = 0.7853982

second, the book refers to bore but is talking bout cylinder diameter thus:

mm converted to cm, 8.3cm^2 = 68.89

third, is stroke and im for now gonna use 92.8mm and convert that to cm = 9.28

forth, the amount of cylinders = 4

hense: 0.7853982 x 68.89 x 9.28 x 4 = 2008.41776376576 so 2008cc

 

If i use the standard g60 bore and stroke then:

0.7853982 x 8.1^2 x 8.64 x 4 = 1780.87596717312 so 1781cc

 

rite lets go back to 83mm but lets use the standard stroke 86.4mm:

0.7853982 x 8.3^2 x 8.64 x 4 = 1869.90619385088 so 1870cc

 

so with the thinking that the 1H block is basically the same as the PG block lets use the maximum cylinder dimension that the bentley manual (described as 2nd oversize) recomends for the PG block, i'm asuming that this is actualy VW's own spec's

i'll also use the 92.8mm stroke

 

0.7853982 x 8.151^2 x 9.28 x 4 = 1936.955554241520384 so 1937cc

If everything ive said is wrong then i might just give up because i really felt sure i had it right but if i am wrong then i feel im not up 2 this engine conversion.

anyway my thinking on the pistons is they are special ones because valve clearence and compression ratio need to be taken into account.

 

i will speak to john but i really wanted to have as much info as i could then i can have sensible conversation with him and also not ask stupid Q's

 

Formulas for displacment, stroke & bore:

cylinder volume = Pi/4 x (bore^2) x stroke

displacement = Pi/4 x (bore^2) x stroke x number of cylinders

stroke = displacement / (Pi/4 x (bore^2) x number of cylinders)

bore = square root of displacement / (Pi/4 x (bore^2) x number of cylinders)

[Guest]

Gareth, your formulae are fine - you'll have to give them time to work out why it's PI / 4 when using the bore (diameter)...

 

An 89.64mm stroke would (technically) give you the 1940cc.

 

Oh, and you've got that forumla slightly wrong... It's not BORE, it's RADIUS that you need to square to work out your engine specs... ;)

 

Formula for engine CC = No. of cylinders x (Pi x (piston radius in cm)^2 x (stroke in cm) )

 

Given that we all know that the engine is 1940cc and the bore is 83mm, it's not difficult to work out that each cylinder has a volume of 485cc... 8)

Bore = 8.3cm therefore piston area in cm^2 = Pi x (Radius^2) = 17.225cm^2

Therefore stroke = 485/17.225 = 28.15cm (2dp)

 

Someone forgot to multiply the square radius by PI....

I 'd love to know what rev-limit you're aiming for with a 28.15cm stroke. :lol:

[Henny 0]

feck, I wondered what was going on... :oops: I've edited the post above to have the correct figures in it... I was somewhat distracted when I was writing that... :oops:

[beavis 0]

Ali G's 'da math' .. see all those maths lessons so many moons ago at school are coming in useful now...

[Gareth 0]

Again thanx 4 all your help :)

 

can any1 shed any light about "Rod Ratio"

looking at a site offering engine internals it mentions using longer con rods for better "rod ratio"

 

Any interesting web pages to look at explaning rod ratio?

is there a calculation/formula i could use??

 

any help welcome

[beavis 0]

Unless you have £$£ to spend on bespoke rods such as 'Arrow' units save your pennies. The stock G60 items are hard to surpass in tearms of build quality and strength. Substitute rods may have more desirable dimentions, but you will compromise strength in favor of this using off the shelf items.

[Gareth 0]

thanx for the info Beavis... ive done a little more searching and found some nice info about rod ratio and at the moment with the info i have, i will be changing the rods trying to keep as close as original rod ratio as possible :)....

its not set in stone but at the moment think its best

[Henny 0]

mmmm nice cranks and parts for sale HERE

 

With the dollar being so weak at the moment, now's the time to get one too! ;) 8)