this just in from somewhere out there [ Archive] - GasSavers.org - Helping You Save at the Pump

another newbie is born

DC2 Acura Integra GSR ::: Cd = .32
JDM 3-stage VTEC SOHC D15B Honda Motor - 1.5 L
Port & Polished Head / 10.5:1 Compression Ratio
Nissan Skyline RB20 Turbo - Zero PSI
Dry Ice Intercooler
5-speed 4.058 Final Drive Ratio
Chipped Computer for Fuel/Timing Map Editing

so far thats what i have going in
right now i have a d15b7 with a blown head gasket burning coolant & oil like its going out of style
the new engine should be in soon
possibly with some alteration of temporary head/block combinations

the turbo will take some time to gather funds to complete the project
but i'm on the edge of my seat deciding to sell my beloved fender jazz bass to complete the project

i drive for a living and have had much experience with changes in fuel consumption
i'm well over 300k miles into my career...
i've had my fair share of beaters inbetweeen
but my primary cars that have taken me there have been:
'99 3cyl Chevy Metro - 100k 46mpg avg
'94 1.5L Civic Vx - 150k 48mpg avg
and now my '94 Acura GSR
i love this car despite its 450lb weight gain over the vx
though i'm using a honda motor which weights i think 100lbs less give or take...
you can see that fuel mileage is my primary goal
and you can likely expect a growing presence

i know honda civics like you know something alot about...lol
i've spent most of my time studying all the factors of engine operation on them
also doing many engine swaps...custom modifications...
and of course...learning
if you have a question about honda civics
you can definately get an answer out of me

i found this site in svoboys signature on honda-tech
so thanx for that

i have many plans for my car...
with no limitation to opening doors to another good idea

hydrogen has been my primary research area...
and is what i see as the best avenue for gains
i've had one mock up unit..but no testing...
and i have a billion different ideas on the best way...

so see you peoples around the site

welcome

Yo, what's up? I wonder what is the method of putting a d series into the gsr? RH77 might be doing this if it's so simple, or at least I want him to.

What made you settled for the d15b vtec? Power or availability?

you actually found a 3 stage vtec engine? My understanding is that they are next to impossible to find.

Anyway, welcome aboard!

Oh ****, wasn't looking, it is 3 stage, what what. They're always for sale on ebay, matt.

Oh ****, wasn't looking, it is 3 stage, what what. They're always for sale on ebay, matt.

that's a common misconception.

I've yet to see a 3stage on ebay, unless I just havn't been looking. I've noticed LOTS of d15b vtec on ebay, but not the three stage vtec.

IMO Japan made a mistake naming all of their engines with the same block code. It makes it very confusing after a while.

I have seen quite a few 3 stagers. One guy on h-t even bought one of them once.

Por ejemplo:

http://cgi.ebay.com/ebaymotors/JDM-D15B-SOHC-VTEC-CIVIC-Si-OBD2-1996-No-Reserve_W0QQcmdZViewItemQQcategoryZ33615QQitemZ805 4828365QQrdZ1

Yo, what's up? I wonder what is the method of putting a d series into the gsr? RH77 might be doing this if it's so simple, or at least I want him to.

What made you settled for the d15b vtec? Power or availability?

I have a friend who put a D15 into an Integra. He said it was cake. It just requires a certain combination of stock mounts.

That's amazzzing.

yes its exactly opposite of putting a b-series in a hatch (civic...etc)...you use the mounts for the engine...the only difference any of the bolt hole spacings between integras and civics in this gen is ZERO !!! lol...the integras have beefier components...but they are all the same dimensions...
the only thing i had to do was use worm clamps on the water inlets
b-series are bigger...and the civic spring clamps didn't fit over the integra hose...

additonal features of the gsr are:
front & rear swaybars
front lower tie bar
beefier springs (heavier motor)
power windows/locks/mirrors/moonroof/cruise/rear-wiper
much comfier seats w/ lumbar for the driver
cabin lights above the rearview mirror
and a chime if you leave the lights on

also svoboy...your cx manifold may bolt on to a b7 motor
but the ports are much smaller and may cause a negative effect as the air is about the enter the chamber
possibly good outcome is more swirl atomizing fuel
but it may be too much turbulence creating too big of a wall of air at the transiton right where the fuel is injected...
worth a shot...but also maybe not

the 3-stage is rated up around 50mph hwy or more
it has the same intake as a d16y8/y5 with egr like the y5
what i'm getting at is that it uses a big (relative to cx/vx) throttle body but still achieves the mileage
also it came stock with a 4.058 (think usdm dx/lx) tranny
the cx/vx tranny is much taller gears at 3.25
using the b7 (dx/lx) tranny i have considerably better performance
the cx/vx tranny was too long for the integra...i had acceleration problems
however...my fuel mileage is exactly the same...
i have had 2 different engines in the integra
stock 3-stage (cx tranny had really bad ISB) couldn't break 35mpg
and the blown b7 motor in there now...gets 30-35mpg
all have had their problems while i get a good engine ready...
i attribute the 3-stage directly to improper timing
all the usdm 96+ civics call for 12° base
i have an obd1 car using a chipped p28 with obd1 maps set at 16°
which makes perfect sense in retrospect
cant wait to get her back in...
though i have another block combination i might try first...doh

the y5 is the usdm civic hx which get about 42mpg - its a 1.6 L
but has the vtec-e technology
the y5 cam actually has more lift than the y8...
but it uses roller rockers which probably offsets the ratio in the favor of more lift on the y8

the 3-stage has more lift (on the wild lobe) than the y8 as well
but it doesn't use roller rockers...
like all the other vtec d15b's it puts out 130ps (about 127hp)
the same as the 1.6L engines...but peak comes in 200rpm below redline at 7000...

for all practical purposes this engine is an economizer
the wild rocker doesn't even ride on the lobe until vtec is actuated
it is then held against the lobe from above and then all 3 rockers are held together by a fairly typical vtec mechanism pushing pins across each rocker locking them together

yeah i took it apart
if you guys want pictures...i've got plenty

The cx manifold does indeed fit, I'm about to post up some pictures in a success thread. I have though about the turbulence issue, and it has me a little worried or happy, who knows, but I think I will eventually go ahead and get a cx head and slap it on there before I do my full engine swap over to the vx.

Pictures!

you know what i really wish i had pictures of
a night i got drunk at a bar in hanover
coming out i stumbled into a huge crowd gathered to watch an hour long parade of naked freshmen make their way across campus
:O

thats where i'm from
i actually used to sneak onto computers in their halls to surf the internet when i didn't have any for a while...lol
dartmouth is great !!!

here a pic from above of all the mechanisms for the intake side
the actuator up top holds the middle rocker against the wild lobe
http://users.adelphia.net/~digitalcongo/d15b/valvetrain07.jpg

here's the first rocker coming off
you can see the normal 16-valve vtec pin (closest)
and the lower solid pin activates the 3rd stage
http://users.adelphia.net/~digitalcongo/d15b/valvetrain08.jpg

here is the egr cover that has 4 mini-runners to each intake port
a good spot for injecting alternative fuels porting the main chamber
http://users.adelphia.net/~digitalcongo/d15b/egrcover4.jpg

Haha, don't try to scare me off of darmouth now!

Very interesting EGR set up there, hmmmmmm.

In any case, why is the turbo set to 0 psi?

removes vacuum entirely from the engine under all conditions
the skyline turbo uses ceramic ball bearings and a ceramic exhaust blade
it should spool up fully well below my cruise speed of 2500rpm (about)
with an external wastegate and a very light spring inside
most of the exhaust gas is rerouted and boost pressure is maintained around zero psi

the brief explanation
an engine during vacuum (its entire operating range) has to work to pull air into the engine...it suffers from this work
using a turbo generally adds alot air and therefore fuel...
performance increases as does volumetric efficiency skyrockets
the engine no longer has to work to get air in...and its actually being forced...
unfortuneately to compensate all the air...fuel must be added...
UNLESS...
you simply dont add positive pressure...but eliminate vacuum
zero psi is like when the car is off...there is still about 1bar of atmospheric pressure...
you aren't adding EXTRA air to compromise air/fuel ratios
you are just removing the pumping losses from the engine

less wear & tear...less work
ALOT of timing advance
efficiency
an open playing field for altering target a/f ratios

So you're just chilling in the WOT column 100% of the time?

no i'm not ready to remove my butterfly from the throttlebody just yet
though redesigning how our cars are controlled should be the goal
there are plenty of other factors besides the air charge that could be more effective in controlling engine speed
more specifically...fuel and spark...
you shut of spark and fuel and the car slows down
clearly the throttlebody at cruise is a hamper on efficiency
cue the pulse & glide efforts...though i could never drive like that...how annoying...lol...
there is a better way...and its likely split time fueling
where up arond cruise you could theoretically hold WOT but only be injecting fuel and sparking every other
its all theory of course...but yes...throttlebodies suck for efficiency at part throttle...
the engine is more efficient at wot

relative to normally aspirated car...yes..it would just above the wot column...
though the physical throttleplate is still only part open

I'm joining late as usual, but welcome! I'm stuck with a '98 Teg LS Automatic, 3-door, and I've been thinking D-Series for a while now. So, are you in school in Cleveland (I'm from Akron originally). I found your GSR in the Garage last week and was impressed. BTW, are you studying Physics?

RH77

i graduated HS in '93 and went to college in boston for electrical engineering for 2 semesters...
i left college because i thought i couldn't afford it...
worse mistake i made (i later found out my father did the same thing...doh)
i maintained a 3.4 gpa ...
i barely started my 3rd semester but had all my books purchased for the entire year...
i continued my education at home...and consider myself to have an associates degree...lol...

i'd love to go back to school !!!

definately do the d-series swap...
though maybe you might want to wait and see that i can at least better 40mpg with one...
i'm absolutely sure i can...but two non-ideal setups so far have been limited at 35mpg...
weight reduction will be the key
i'm trying to decide where i will live for next winter...
and that will ultimately decide if i remove the abs brakes or not
thats like 70lbs !!!
but i wouldn't remove them if i move down south...

wow 35 mpg but all that power on tap, super jealous.

read some more of my posts...
nothing is installed yet...
everything at this point is mathmatically crafted...
no real world values

the engine currently in my car has a blown headgasket at makes any passenger or nearby vehicle drivers nautions with coolant smoke and burns about 2-3 quarts of oil every week or so...
also i stripped the timing belt tensioner bolt and the belt is too tight...
the head is on the edge of seizing...

hopefully i will swap this weekend...
we will see what combination i end up with

i'd love to go back to school !!!


It's never too late to go back, but it's really hard once you've left. Don't give up man -- you've got some great ideas here, and your GPA was good too.


i'm trying to decide where i will live for next winter...
and that will ultimately decide if i remove the abs brakes or not
thats like 70lbs !!!
but i wouldn't remove them if i move down south...

I got out of Ohio because the job market was crapola. I ended up back in KC, but we get our fair share of ice/snow/sleet, so ABS is required here (I had a '99 Si Coupe, and really missed it - not available). If you can handle the heat, look for an inexpensive school down south with some credibility.

Anyways, I'd probably get a project car for mileage since the B18's in great shape -- I just need to figure out how to get the best city mileage. The low Cd of the Teg lets the highway MPG even-out the city, but I keep getting an average of 31.

RH77

ABS is not recommended for winter driving...
they lock up in snow & ice...
currently my front axles are non-ABS...so its semi-disabled

i'm with you on the poor average mileage
the rear tailgate is a windcup and desperately needs diffusing
there definately seems to be some kind of limiting factors
though its probably not just one thing

overall body weight
small aerodynamic nuances that exponentiate
like the recessed headlights, rear bumper cover (as mentioned)...

i'm weighing heavily on doing a 99-00 front end conversion
not really for uniqueness...too much of PIA for that...