Another Advise on polo G60 people ...

[djtez]

Well i another sucker thats going down the G60 route ...

Basicly im wanting this done within a month!

Right now ive searched on here and club polo and got some good ideas but not everything!

QUESTION 1
Pistons, I've looked into the more popular Wossner pistons 77mm 1341cc 8:0:1 standard compression
JE pistons at 8.5 : 1 and the high comp accralite 9:1 ..

now am going to be running BVH heavily ported, thin metal gasket 51mm throttle.
Charger will be full blend g60 with 68/70mm pulley!

should a stay 8:1 comp with thin gaskey due to the much higher boost?

QUESTION 2
Rods ! i have looked into PC H Rods, ACL and also Wossner rods..
Do i need to change them? Is it an issue that has happened regular ? Wossner Piston & rods £879incl VAT



Thank you very much in advance for helping me with this! Its Clubg40 that builds my car

[dub-disaster]

pretty sure rods dont need upgrading i think i remeber reading somwhere that because they where deisnged by hand (ie not by computer) and the g40 was a test car for the g60 golf they where very overspecced and good for 300bhpish i think although im pretty sure almost all running 200bhp + still have standard rods.
As for piston choice if it where me personaly in your situation id go with wossners as its going to be supercharged you dont need more torque of boost as you have no lag and it will mean you can run more boost without retarding your ignition timing. although maybe if the car is your daily consider the JE pistons, there are planty of threads on this matter though try searching for compression ratio, C/R , forged pistons and 1341 cc , 8:1 vs 9:1 etc..etc..
one good topic is here http://www.polog40.co.uk/forum/index.php/topic,2319.0.html
On the subject of head gaskets i think the standard one is up to the job i run it with 22 psi as do a few others although the metal one is an option if you feel you want to increase the CR slightly or you cant find a standard one !!

Good luck with the build and take some photos and get a thread up when youve got time as id like to read about it

[Jezza-7]

You boost pressure will only be just over a bar anyway.

[djtez]

Boost pressure on a g60 charger full blend with on 68 toothed pulley on a G60 is over a bar,
People on sites reckon more towards 1.3bar with the Polo's smaller capacity ...

well in theory that should be correct, same amount of air but in a smaller cylinder..

on motor-talk.de they are all quoting 1.4 bar with 68mm pulley.

[djtez]

thanks V much for the post dub-disaster

after numerous google searches only a handfull of ppl have changed there rods on high output g40's and mostly for safe keeping!

[Jezza-7]

A mate on the corrado forum said he has the same setup as me, overbore 1.9, head work etc and runs 12 psi with a 68mm pulley.

[djtez]

ye i saw that post on the corrado forum, but thats on a 1.9 not a 1.3

hold on ...

[djtez]

http://www.polog40.co.uk/forum/index.php/topic,7258.0.html

http://translate.google.co.uk/translate?hl=en&sl=de&u=http://www.g-laderseite.de/forum/viewtopic.php%3Fprintertopic%3D1%26t%3D11674%26postdays%3D0%26postorder%3Dasc%26%26start%3D0%26sid%3D80169bba69b37fc72f2a3a6d920023e8&ei=N-1tT4iKAcjN8QPN2PC_DQ&sa=X&oi=translate&ct=result&resnum=5&ved=0CHEQ7gEwBA&prev=/search%3Fq%3Dpolo%2Bg60%2BDruck%26hl%3Den%26biw%3D1280%26bih%3D609%26prmd%3Dimvns

The second site is the g-ladersite in translate to show on a standard cam head and inlet the g60 charger produces 1.4 bar on a 26tooth pulley ... that is what i've seen alot on forums and websites...

i assumed this was right ?

[Jezza-7]

yeah but every engine is different. All depends how much porting is done and charger porting obviously, as said it will only just be over a bar, 1.3 is just over a bar.

[djtez]

Yes very true buddy! think my spec is very similar to yours..
BVH heavily ported by man in shed, 1341cc etc...

i think this set up will easy see 1.3 bar.

I'm still indecisive about 8:1 or 8.5:1 really..

Also alot of set up still using G60 injectors!... so im double thinkin if a need 310cc red tops or if thats just a peace of mind..

Jezza have you opted for the 250kpa or 300? ...

Also! are you using the G60 conversion brack with or without the tensioner running the toothed belts

[dub-disaster]

Remember a heavily ported big valve head my flow more up top but due to the lower velocity in the ports and lower rpm there will be less tourqe and it may use a smidge more fu because of it along with standard compression might lack low end of boost grunt just a thought, not sure whG your use of the car will be to be honest.

[Jezza-7]

Mines not big valves, didnt see the point in them really.

But i would get the red top injectors. Its better to be safe and i do remember someone saying something about the injectors were at their limit almost with a g60 lader.

I would stick with the standard compression ratio imo. Im looking at the 1.5 map sensor.

At the moment im looking into the bracket with the tensioner as im not sure if im using toothed pulleys yet. Probably will but the bracket with tensioner can be run with toothed belts, just need a longer belt.

[djtez]

Big valves will help escape the gases ! a good Big valve head with porting will be good for 10bhp on most specs.

A can see the advantage of the bracket with tensioner... but the non tensioner bracket, can i still adjust the charger just the same as the G40 one ?

Ive read on corrado forums that the injectors are roughly maxing out about 200bhp high up the revs..
some other quotes have been 49bhp per injector :S dono how they guessed that but ye 310cc seem to be the option..

[djtez]

Well! Good news a purchased a G60 supercharger..!

Jabbasport stage 4.
10k miles since rebuild ran on 68mm pulley

But the charger has lay for 2 years untouched and also last service rebuild was done by G-werks!

Now on java site it only shows stage 4.. But a assume a could get it Ported more!
How much boost difference will show from st4 and full blend?

[PR23M3K]

I have got G60 injectors and at 1,4 bar of boost (28 teeth pulley) they are almost at their limit that in PY engine is ~200 bhp.