Compression rates

[verm69]

Hello,


Can anyone tell me...

the stock compression of a ae101 GZE?

how much i can expect to see the compression raise using a TRD stainless .5 gasket over a stock gasket?



I have a TRD stainless 3 layer gasket that i'll be using for my head, but just thought about compression rates... i don't want it going up too much as it has a sc strapped to it

cheers

dave

[rthy]

stock is 8:1 for the bogport and 8.9:1 for the smallport, I am guessing yours is the later

I can work out the change with going to a 0.5 gasket and get it back to you

BTW have you seen my new article in the FAQ?

http://www.ae86drivingclub.com.au/faq/inde...pression-ratios (http://www.ae86drivingclub.com.au/faq/index.php/BY_ENGINE/4age/compression-ratios)

I don't expect anyone to understand my jibberish though

[verm69]

i knew you or Jonny would know ;)

Thanks Sam :D

[dustyae86]

I noticed sweet F all difference between a TRD one and a stock one.. don't really think it is worth it, but if you ave it already then why not

[pope]

Sam you may want to think about adding a section on how to physically measure your compression ratio.

Known variables are nice but aren't truly known till they are measured ;)

Just nit picking but looks like a good writeup other than that.

[rthy]

ok if stock is 8.9:1 (it is a smallport right?) then it will go up to 9.5:1 with the 0.5mm gasket, there a good chance it wont seal anymore though without a head skim.

pope: not a bad idea at all, however one of the most used ways to measure the chamber volume is to put the piston at TDC with the valves shut (compression stroke) and then pour oil down the spark plug hole. This is all good for iron age engines that have spark plugs out the side but with twin cams the spark plug tube makes this very hard to tell how full it is. There is another manual way but it takes more, one of my latest books explains more than that and will hopefully shed some more light on the subject for me.

[pope]

Cool cool

I have only just started looking into it also for my future turbo projects.

Most places make mention of plexiglass, die, a slightly more viscous than water substance and an engine in many pieces.

Lots of effort but if your doing any serious work it seems well worth the time to know exactly what compression you are running.

[reecegze]

so for an 8 0 1 engine .5 will make it got to 8 5 1 ? as off boost mines alittle bit of a pig

[rthy]

pope: couldnt agree more

reece: it will take it to 8.47:1 so yeah pretty much 8.5:1, I highly recomend you instead run the more common and cheaper 0.8mm gasket and then deck your head.

[verm69]

head's all ready been decked and it's been made true ;)

you think i might have to get the block skimmed?

i was worried about it not sealing since it's so god dam thin...




your the man sam... love your work

[rthy]

do you knwo much much was taken off the head? I have to factor that into the calculations.

No infact lets go from the start, could you explain what setup you have, as in are you still using a charger or a turbo now?

[verm69]

will be using the SC12 running 13psi

can't tell you how much was taken off the head :(