compression

[crshbndct]

instead of changing the boost level i was wondering about chaging the static compression ratio to maybe 8.5 or 9 figuring that according to this website:

http://www.turbofast.com.au/TFcompB.html

with 9:1 cr, i would only need 12psi to make the same power as 7.6:1 and 18psi

higher cr also means better off boost driveability

[crshbndct]

bump

[QikLude]

if you shave your city head to the max it will give u 8.2?:1 max, around there somewhere anyway...

Ive just done that to my new head now
cant wait to fire it up!

Jw

[crshbndct]

well yeah. but thats still gotta be better than 7.6?

[QikLude]

hell yes!!

much better performance off boost, and quicker to come on boost.

easy power to make without winding up the boost

Jw

[crshbndct]

ok so assuming i got it to 8.2:1 would that mean that i could run a bigger turbo and have less lag as well?

or maybe run 17 psi on the stock turbo, have no lag, high power and better off boost driveability, and make the same power as 7.6:1 with 21 psi but no need for big turbo to do it becasue its only having to push 17psi

[QikLude]

[quote author=crshbndct link=board=GEN;num=1065008595;start=0#5 date=10/07/03 at 08:49:49]ok so assuming i got it to 8.2:1 would that mean that i could run a bigger turbo and have less lag as well?

or maybe run 17 psi on the stock turbo, have no lag, high power and better off boost driveability, and make the same power as 7.6:1 with 21 psi but no need for big turbo to do it becasue its only having to push 17psi[/quote]

yeah your on the right track.

Ps - a turbo will always have lag...

[crshbndct]

yeah i know a turbo will alway lag (except in xr6 turbos) but there will be less lag than with say 7.6 and a bigger turbo to achieve the same power goals

[Colza]

This looks like it will be a good start towards assisting my T04 in the spooling up department (needs all the help it can get!) How much did it cost to get your head shaving done? Port and polish etc etc aswell?

[Turbo2]

Hmmmmm Yes I would be interested in price's tooo

Cheeers Turbo2   ;D

[city_boy_t1]

I had my Civic Si head skimmed at the "Cylinder Head Shop" on the shore they rebuilt the whole head and included heavy duty valve springs and skimmed the head by 2mm and ported and polished it for $800.

I presume it will be cheaper to do a city turbo head as you have to pay separate for every valve and every valve spring and since there is only 8 that means in that department it would be twice as cheap as for the skimming it would be the same price but as for porting it would be cheaper.

So my guess for a city turbo head rebuild, port and polish and skimming of the head about $ NZD500

[BOOSTBOY]

I shaved the head down past the indicators on my old CityT and it didnt help all that much...  Still very laggy with the big turbo.

[QikLude]

[quote author=Turbo2 link=board=GEN;num=1065008595;start=0#9 date=10/15/03 at 11:42:16]Hmmmmm Yes I would be interested in price's tooo

Cheeers Turbo2   ;D[/quote]

hmm well rebuild kit for the motor and about 1 hours labour fixing the head specialists pc

I was quoted around $1300 to do a complete full nasty build
thats with enlarged exhaust valves full port etc, new valves etc of course, so quite a lot in parts.

i think a standard rebuild was around $400 or so.

Jw

[crshbndct]

can get it done in tauranga for about 150