Thread: turbo gurus (guri ?)

9.5:1 with puffer is gunna need 98 octane fuel to keep it happy.

a rethink may be in order (or a decomp. plate)

Straight LPG should help (sorry - didnt fully read post) so a GT25 dialed down should be ok.

Guru is a Hindi word, not Latin - hence the plural is gurus.

John

go buy a copper de comp plate from ACL.
your comp ratio will be closer to 8.0:1
then bolt a T04 onto it. these are as common as and should be fairly cheap.

cheers phil

ps is it a blue/black 202??
the con rods are beafier in the blue/black. what everybody calls ''starfire'' rods.
and you better look into a head stud kit! the std head bolts wont be up to the task.

i was always under the impression that a ''gas'' motor had to have a higher than std compression ratio??


cheers phil

Originally Posted by discowhite

i was always under the impression that a ''gas'' motor had to have a higher than std compression ratio??


cheers phil

Don't know but I do know gas and turbo's love each other.

A national fuel quality standard for automotive LPG called the Fuel Standard (Autogas) Determination 2003 took effect on 1 March 2004. The Determination outlines the standards and testing methods for Autogas in Australia. To see this document, please go to: http://www.ag.gov.au/portal/govgazonline.nsf/0/0DB540E565153748CA256E05001D2445/$file/S503.pdf. It is interesting to note that the minimum motor octane number set for LPG in Australia is 90.5 (approx 102 RON). While this is the minimum, some retailers may in practice offer a higher-octane product.

If you have LPG with 102 RON, I think you would really be pushing to run 9.5:1 with a turbo, in an old iron head engine.
I would go for comp in the 8s,with a lowish boost and some sort of electronic retard.
Regards Philip A

From my experience with supercharged and turbocharged petrol engine, ones that were not built that way by the manufacturer that is, 9.5:1 is way too high, and you need to keep boost below 8psi over atmospheric. An intercooler would be good. A knock sensor switching water injection is good. If you are going to have high boost then you need to get someone to design and make a boost retard canister to replace the vacuum advance item. About 1 degree retard at high boost does the trick. Or, get some form of programmeable electronic ignition (Jaycar kit perhaps) that will do the same, maybe also switched by a knock sensor.