new engine plans

[Bunger]

Originally Posted by Sludgy

A hand grenade. With 13:1 and pump gas, it's going to be raining piston shrapnel.

Its do-able... I've run 12.5:1 on pump gas... but i had to retard it a few degrees and run a little rich.

[molecule]

360/38 (teeth) = 9.47° per tooth
that should lower my power band a good fortune

i think if i can keep intake temps low enough
detonation can easily be fended off
dryice sublimates @ -109°F ...
in a bath of acetone it maintains a temp of -107°
my intake air temps should be around 0-35°F

i think all in all i can break 40mpg
thats my goal
but the engine might lend itself to erratic acceleration...lol

i have to try it...because its sitting here...
and it will be a month at least before i can complete the turbo build

i would normally never compromise my ability to have a reliable vehicle...
but i currently have no open contracts for work...
so its time to play

oh wait...9.47 is cam degrees
YOUR RIGHT
its actually just under 19° crank...
well see if i have some funds for a adj. cam gear
maybe someone will buy my d16a6 si intake

[molecule]

well i dont think i will do the high compression...
i'm not as strong minded as i had hoped...lol
i'm picking up my ported head tomorrow...
and i'll probably slap that on the b7 block for 10.5 c/r
and then start getting the turbo stuff together

though it seems there is an inherent problem with my plans for the wastegate idea...
turbo's do not spool up unless at WOT...
at least thats what i'm hearing...
i mean, i went way out of my way to get the most efficient turbo on the market in a compact size...
the skyline turbo uses ceramic ball bearings and a ceramic turbine...
it should spool up well below 2500rpm...
but i guess i will just have to see if it works at part throttle

[GasSavers_DaX]

On my civic, my turbo would spool well below WOT. If you want it to reach full spool, WOT was the quickest way to get there though. My turbo wasn't even that efficient...your basic off the shelf Turbonetics T3/T4 w/standard 270* bearings.

Spool has a lot to do with turbine sizing compared to displacement too. On my 1.8L Civic I had a 0.48 AR turbine - it spooled so freaking fast (a friend of mine said it felt like a BB turbo) but I had to trade off some top end power (or volumetric flow rate) for the fast spool.

I'd say stick with a small turbine size and you'll spool well below WOT.

[Bunger]

I agree, you should see boost at fairly low RPM, even at part throttle. Turbine size is going to make a good difference, and keep the exhaust post-turbo as free flowing as possible.

There are ways to cheat the turbo into spooling sooner, but most are not mileage friendly. Look at WRC cars, they retard the ignition and dump a ton of fuel to get those snails spinning off the line... hard on the turbo and your mileage.

Which turbo model will you be using? A T28?

[Bunger]

I'm guessing the ceramic one off the RB26? Pay close attention to the condition of that turbine... the ceramic ones don't hold up to detonation well at all.

[molecule]

duely noted on the detonation factor
here's a great (rare?) thread on honda-tech about "det-cans"
http://honda-tech.com/zerothread?id=1555006

good news about the turbo...i feel ALOT better...it should work
i had some dsm tuner guy really trash talking me last night and i was sunk low on over a year of my studies thinking it should work..
man some people...
he made some valid points and has alot more experience than me
anyways

its an rb20 unit from an r33
here's all the specs i got on it
20t comp wheel 42x59
comp cover .50 a/r
turbine wheel 51x43
.4 a/r there abouts
around 250hp max
ceramic ball bearings...ceramic turbine

there were two versions of this turbo produced...
the later was bigger and could support over 300hp stock
i'm 90% sure this is the smaller...though i dont really know...
one nice thing that should help me further on the later skyline turbos
the compressor has a bigger a/r than the turbine...
something you usually only see on diesel truck turbos
that should yield a little extra oomph as well for my goal !!!

thanx so much for the feedback
pick up the head tomorrow
the plan is alive and well !!!

[GasSavers_DaX]

That's some interesting **** about the det-cans.

[molecule]

got my head
WOW

he even stamped it 4 20 06
happy 4/20 everyone

just need a d-series turbo manifold
external wastegate
intercooler
a bit more piping
turbo oil lines
and downpipe fabrication

not too far off
the amputeens (lol) have commited to buy my fender jazz bass soon
so hopefully will have this completed

[molecule]

new plan...(i didn't plan on this being my 134th post however...read on)
do things right the first time...
i think i will try and build up a halfway decent bottom end for this motor...

i found some B16a rods in my garage...
b16 rods happen to be about the same length as the d15 ::: 134mm
actually 134.366...so yet another bump in compression for my turbo motor...bah...
the big end bore of the b16's will clamp right onto the jdm d15 crank...which has the same d16/b16 rod journal diameter...
so the only thing left to do is bush for the wristpin from 21mm to the d15/d16 19mm...
oh and i think a small bit of block notching

current compression calculations with my setup:
stock d15 134mm rods - 10.43:1
bushed b16 134+mm rods - 10.8:1