R31 Rb30E Afterkamarket Recommendations?

[StevenCJR31]

Not planning on going fast bro

okay i thought thats what you were aiming for when you were asking about air filter/ muffler/extractors/exhaust as these mods will do f@#k all for your NA 30E, trust me on this as ive tried it all before

[LayneGXE]

Yeah was made in march though when i wanted speed etc.

Have come a long way since then.

All i'm doing is cosmetic'ish things. New wheels, and coilovers thats all

[Pattey21]

Just for ideas i had a 31 prior to my 33. for wheels run 8" wide all round with a zero approx offset. Suspension ran new kyb shocks with 2nd hand kings/lovelles etc springs. Whitline swaybars, s13 control arms with hr31 tie rods. This is a good cheap option. get parts from r31 club and ebay. Wheels ae86dc or nissan silvia forum etc even ebay or otomoto or vr motoring or go through jesse streeter etc

Edited July 11, 2012 by Pattey21

[Berk]

Be rad and shave the head, add RB25DE pistons, nistune, 818b cam and RB26 ITB's with trumpets.

Would be rad.

Rad.

Edited July 13, 2012 by Berk

[StevenCJR31]

Be rad and shave the head, add RB25DE pistons, nistune, 818b cam and RB26 ITB's with trumpets.

Would be rad.

Rad.

would using the 25DE pistons increase the CR of the 30E? if so by how much?

[Berk]

Yep, don't remember exactly but it's around 10-10.5.

[Gerg_R31]

thats a bit exagerated in the raise in compression

[StevenCJR31]

thats a bit exagerated in the raise in compression

Hey Gerg R 31, whats your opinion on the amount that the compression ratio would go up too? have seen info on this on the R31 SKYLINE CLUB forum and there is a lot of differences on what ppl think it would go up to

Edited July 15, 2012 by StevenCJR31

[Gerg_R31]

its something that will have to be measured to get an accurate measurement,

i.e the rb26 im doing now 13cc dome 87mm pistons, was told it is all standard, pistons sitting 10 thou bellow, 68cc chamber (pretty big cc for a stock head) it is 7.95:1 with a 1mm/ 40 thou composit head gasket

the same pistons in another rb26 started at 8.65:1 with a 63cc chamber and a 5 thou piston to deck

with the 25/26 pistons they always sit heaps down the bore in the 30 block,

then there is the head, we can guess how much the chamber is but then it could have been ground before, or reco'd before with heaps taken out of the seats

though i guess you can easily get to 10.5:1 with them pistons and some machining, but easier cheaper etc could be just to buy pistons with a bigger dome with the right pin height

[Berk]

Wouldn't be that expensive to buy some used 25DE pistons, new rings, hone the block and machine the head would it?

[StevenCJR31]

^^^ this is what i was thinking of doing, being the cheap ass that i am i have a 33 head (slighly shaved) thats already had the mods done to build a 30DET plus a 30E block that has an undamaged/unworn bore thats within original tolerance, from what ive read in the forced induction section i would end up with AROUND 8:5 to 1 CR using the 30E pistons. . . .i would like to bring it up to 9:1 CR and IF i can do that using 25DE pistons then i will go down that path(i have a low K RB25DE engine)

[Gerg_R31]

static comp ratio formula;

http://www.skylinesaustralia.com/forums/topic/378823-engine-internals-comp-ratios-general-info/

if your dont have a burette use an eye dropper 1ml = 1cc

head cc's

spread vaso around the edge of the chamber

place a perspec plate with a hole drilled in it on top

to cc piston dome

option A make a mould out of play dough of the dome and cc that

option B put perspex plate over dome, use play dough to seal the area around the piston,

cc that ( C )

measure outside of the top of piston (usually 1mm smaller) ( A )

measure dome height ( B )

( A ) x ( A ) devide by 4 =

= x 3.142 x ( B ) =

= devide by 1000 =

= take away ( C ) = dome volume

[StevenCJR31]

static comp ratio formula;

http://www.skylinesa...s-general-info/

if your dont have a burette use an eye dropper 1ml = 1cc

head cc's

spread vaso around the edge of the chamber

place a perspec plate with a hole drilled in it on top

to cc piston dome

option A make a mould out of play dough of the dome and cc that

option B put perspex plate over dome, use play dough to seal the area around the piston,

cc that ( C )

measure outside of the top of piston (usually 1mm smaller) ( A )

measure dome height ( B )

( A ) x ( A ) devide by 4 =

= x 3.142 x ( B ) =

= devide by 1000 =

= take away ( C ) = dome volume

^^^working that out will keep me outta mischief for awhile. . . altho i didnt want to go to the expense of fitting the 25DE pistons to the 30E rods/bottom end to find out what (if anything) it will do to the CR. . . . sorry for hijacking your thread LAYNE GXE!