LPG has octane over 100 and burnes slower than ULP so likes compression and higher initial advance. His compression is fine. Advance curve is not:eek:Quote:
Originally Posted by mike 90 RR
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LPG has octane over 100 and burnes slower than ULP so likes compression and higher initial advance. His compression is fine. Advance curve is not:eek:Quote:
Originally Posted by mike 90 RR
It has less BTU's than petrol, hence why it can never match economy litre for litre, but will sustain knock much better allowing for more compression and/or timingQuote:
Originally Posted by mike 90 RR
If he went back to 9:1, then all the machineing was a waste of coin and it'll be slower again
If he just controlled timing correctly and finished the job properly, it wouldn;t be an issue, you can;t half ass a high compression engine build;)
Thanks for the replies guys.
In the weeks leading upto pulling the heads off I had it running rich as I was playing around with mixtures. So that is quite possibly why there is so much carbon buildup inside. That and yes... the valve guides are letting some oil in. When I run the engine under a lot of compression braking (say down a steep hill when off road) the engine will blow a bit of smoke for a little while afterwards until it clears.
Since the bores a glazed it is possibly that it could be sucking oil up past the rings too further contributing to the carbon buildup.
Anyway, at the end of the day I built this engine with my dad when I was 18. I have learnt a lot from this stunt and when I get onto another project engine I'll probably give the 12:1 CR another go on an LPG injection engine.
The repairs I did were not perfect. But my intention was to get the car back on the road and last say another 12-24 months.
We did do a bit of cleaning before putting it all back together though
https://www.aulro.com/afvb/images/im...2008/07/24.jpg
https://www.aulro.com/afvb/images/im...2008/07/25.jpg
https://www.aulro.com/afvb/images/im...2008/07/26.jpg
https://www.aulro.com/afvb/images/im...2008/07/27.jpg
https://www.aulro.com/afvb/images/im...2008/07/28.jpg
https://www.aulro.com/afvb/images/im...2008/07/29.jpg
I will play around with the timing. It is true that there is a fair amount locked away there. I'll probably try locking out the mechanical advance and see how that goes.
She will go for another 200000 ks now;) Seriously it will last heaps longer with out detonation:). Its a good one for your 1st:) I'll vote yes to stick with CR you have on gas on the next one. (Strocker may be:D)
Alright alright, since you guys kept insisting:
http://www.aulro.com/afvb/members-ri...tml#post788053
Ok I finally got round to doing another compression test post changing the head gasket.
Old Results:
1- 157psi 2- 174psi
3- 174psi 4- 167psi
5- 148psi 6- 181psi
7- 162psi 8- 203psi
New results:
1- 160psi 2- 180psi
3- 180psi 4- 170psi
5- 170psi 6- 170psi
7- 160psi 8- 190psi
Hmm, 1 and 7 are still a bit interesting... ahh well. The startermotor is tempermental and the results are greatly influenced by it... But At least they aren't low I suppose.
I also took a photo of the plugs:
Plugs 1, 3, 5 & 7:
http://i8.photobucket.com/albums/a16...808_180201.jpg
Plugs 2, 4, 6, & 8:
http://i8.photobucket.com/albums/a16...60808_1805.jpg