zyounker

Ok, I know there are a alot of turbo 1st gen projects in the works.. So who all has one and what are the stats/goals???


BTW i want projects, not dreams sorry...


So i'll start:

1984 GSL-SE
13BT /w T04E
FD upper intake
TII Tranny
Haltech E6K
2x550 primary injectors
2x1600 secondary injectors
NPR intercooler
Mazdaspeed Aluminium radiator


Thanks,
-Zach

Directfreak

iTrader: (2)

OOH! ME!!


1985 GSL-SE in Mint condition - Check...
1995 COSMO-J-SPEC (stock port) - Check...
1995 COSMO Intake - Check...
Haltech E6K - Still waiting for more prices/Ebay
T-04S or T-04E - Unknown A/R with Cosmo Engine??
3 MSD 6A'a (Anybody got some for sale?) - Check... (need 2 more)
Isuzu NPR Intercooler (front mounted) - Check...
TII Tranny - Check...
Bosch Fuel Pump
Braided Fuel Lines
2x550 Primary - Check...
2x1200 Secondary
Re-Routed Battery to Passenger Bin
Autometer Ultralights Gauges in the A-Pillar and under the radio
Clutch - ??
Pressure Plate - ??
Stainless Steel Brake Lines
Hawk Racing Pads for the Brakes

Eventually:
Mariah Mode 1 or Similar Widebody..
Different Rear End
Small roll cage in car
More Boost

Immediate Goal:
325-350 rwhp at 12lbs of boost (conservatively)
375-400 rwhp at 15lbs of boost (conservatively)

This is prettymuch just the drivetrain, I want to do more to the body, interior, stereo, etc. But the Speed has got to come first!

Richard Miller

well this has been so damned difficult to get going it might as well be a dream. But here is a run down of my status.

81 GS

sound deading removed, beat the tar out on a 15 degree winter night

85 LSD tougher axle than the 83 and earler for thoes who are not in the know.

15 inch Wed Wheels in polished aluminum see avatar

3rd Gen seats

Flawless dash & headliner A rareity in sunny Central Washingon

The engine bay is painted and freshened up. polishing where applicable

GTU spoiler

Glass Moonroof

I am doing a black on black with as much polishing as I can do.

Lost my job so life goes on but the car has came to an abrupt halt.

peejay

Ported 12A (porting TBD)
Blowthrough carb (carb TBD, possibly Nikki, probably Holley for simplicity)
Single turbo (probably Holset, possibly T3 "Super 60")
T2 trans
Bets as to how long the engine lasts before the rear housing breaks at the upper dowel

Directfreak

iTrader: (2)

Holley = Simplicity
Holley = Flooding out after a boosted run.
Holley = Hard to start.

It is the simplest, and easy to get a blow through bonnet for it as well, but they do have quirks that you'd have to get used to (as stated above)

Don't mind me though, if I went blow-through, it'd be a Holley too

riffraff

why? why not do a blow through system with a webber?

chuckmorgan79

i recently picked up a BAE draw through kit...
i've heard mixed reviews....
i'd really like to convert it to a blow through and add an intercooler...any suggestions? i'm not looking for much hp, maybe 210 @ the flywheel.
has any one had experience with the kit?

peejay

That's why you go with a bypass type regulator and put it as close to the carb as possible! That way fuel pressure at the carb drops immediately when boost drops.

I've been doing my homework on the setup for the past couple years

peejay

Money. Webers cost more - more for the manifold, more for the carb, more for the hat, more for tuning parts.

moremazda

iTrader: (4)

Hey peejay, since you've got a few years research on this blow through deal are you familiar with modding a Weber yet? I have been told by Pierce manifolds in New York that the DCOE 150's are turbo ready, they just need to be jetted. Have you heard of this? Do you know if the kit that Mazdatrix carries is the 150 model? One more, What is the concensuse on the jetting for a blow through Weber setup?

Ryan

peejay

DCOE 150? Huh?

A Weber will have a name like 45 DCOE - the number is the size of the throttle plate bore in millimeters, DCOE means the type of carb. (basically 2-barrel, simultaneous actuation, sidedraft, forgot what the E means)

I don't know about tuning them for blowthru operation, but as i understand it you just tune it like any other carb, except start too rich and work lean until it's right. As the guys on the blowthru mailing list say, you can run rich many times but lean only once!

moremazda

iTrader: (4)

As in 45 DCOE 150, 48 DCOE 150.

Okay thank you, What is the differance between a rising rate FPR and a by-pass type regulator?

Ryan

REVHED

A rising rate FPR has a boost signal source so the fuel pressure rises with the boost pressure. I'm not sure what a bypass regulator is.

peejay

I've never heard of numbers AFTER the letters. Can you provide a link?

Okay - time for a treatise on fuel pressure regulators. Let's hope my computer doesn't crash on me...

First off, some basics - Fuel pumps do not create pressure, they supply a volume. Restrictions create pressure. For example take a garden hose with an open end - water runs right out of it and there is no pressure in the hose. Put your finger over the end to restrict flow - the hose will jump, indicating that it now has pressure in it. The restriction can be anywhere in the system - let's say your annoying kid sister squeezes the hose near the faucet. Now the pressure at your thumb is reduced because your sister added a new restriction.

Let's start with what we normally use on carby cars - like for example the Holley regulator. Typical setups with the regulators have the fuel system "dead headed" - which means the fuel system dead-ends, there is no return line. The regulator restricts flow so that the is a constant pressure between the regulator and the carburetor.

12A models have this setup (the regulator is built in to the fuel pump) with a slight difference - there is a return line fitted with a small orifice in it. The orifice is there to bleed off pressure, which helps fuel pressure from fluctuating, as well as making life easier on the pump. Pumps supply a volume, and they prefer to keep supplying a volume instead of working hard against nothing, which is what would happen if the pump were turned on with the engine off and there were no return line. Call the return line in this case a "volume bleed", so that the pump is always moving fuel.

Now, let's take a bypass type regulator. This is the system used on fuel injected cars. This regulator requires a return line. The regulator is placed between the fuel injectors and the return line - it's on the return side of the fuel system. The fuel pump supplies a constant volume and the regulator bleeds off - bypasses - the proper amount of fuel so that fuel pressure before the regulator remains constant. Note the difference - the bypass reg cares about fuel pressure before the regulator, the Holley type cares about fuel pressure AFTER.

Bypass regulators typically alter the fuel pressure as a function of air pressure. On EFI cars (except throttle body injection) the fuel injector is in the manifold and is subject to vacuum, or pressure in the case of a turbo car. Fuel injectors do not inject - they are merely little valves that open and close. Fuel pressure does all of the work. There would be a big difference in flow if the fuel pressure was a constant 42psi, depending on if the manifold was at perfect vacuum or under boost. So there is a vacuum hose connected to the regulator that alters the fuel pressure, so that fuel pressure is a constant pressure over manifold pressure. (We call this "base pressure") That way the fuel flow through the injector is constant no matter if the manifold is under total vacuum or under 40psi boost - the regulator makes sure the pressure is always the manifold pressure + base pressure.

With a blowthru carb, you have to increase fuel pressure when the carb sees boost, otherwise the boost could prevent the fuel from flowing in. (If the fuel pressure is normally 5psi, then at 5+psi boost it will be pushing the fuel back through the fuel line since the air pressure in the carb will be greater than fuel pressure!)

If you use a deadhead type regulator with a blowthrough system, and reference it to boost, bad things will happen when you come off boost. If your normal fuel pressure is 5psi, and you're running 10psi of boost, then there will be 15psi of fuel pressure at the carb (remember the regulator has been referenced to boost). Now you let off and boost falls away. Now there's regular old atmospheric pressure at the carb. But the fuel pressure at the carb is still 15psi! Fuel cannot flow backwards through the regulator. The excess pressure blows the needles off the seats and floods the carb, and your car runs like crap when you go out of boost.

Now let's do the same thing with a bypass type regulator. You come off boost, yada yada. Except now, since the regulator is only a variable restriction in the return line, good things happen! The regulator sees the reduced air pressure and automatically bleeds off the excess fuel pressure, and the fuel pressure at the carb remains exactly where you want it to be.

Note that the carb setup is slightly different - we don't care about manifold vacuum, we only care about the pressure that is in the float bowls - meaning the pressure between the turbo and the carb.

One last thing - RRFPR's. Those are crutches for too-small injectors or inability to tune a computer. What they do is increase the BASE pressure when manifold pressure goes above atmospheric. Meaning, if base pressure is 42psi, then fuel pressure would be 42psi at zero boost. With a regular setup, fuel pressure would be 52psi at 10psi boost (remaining 42psi over manifold pressure). With a RRFPR, fuel pressure would be over 52psi - if it's a "3 to 1" regulator, then the regulator adds 3 psi of fuel pressure for every 1psi of boost, so fuel pressure would be (math, math) 72psi. This works for boost enrichment, sort-of. It's not ideal because fuel flow does not increase linearly with pressure - you have to quadruple pressure to double the flow through the injector. RRFPR's cannot be used with carburetors and SHOULD not be used as a crutch for EFI cars, because they suck.

REVHED

Thanks peejay, that was a good post.

moremazda

iTrader: (4)

Thank you peejay.

Now, we have a bypass regulator taking it's boost signal from the area between the intercooler and the carb. What happens when you shift under boost? The preasure spike sets off the blow off valve it also pressurizes the float bowls, and the pressure regulator.
Is it safe to assume that as long as the forces on both sides of the float bowl are raised equally (ie "boost" above atmospheric and fuel pressure above base pressure) everything should be happy, and will work when the throttle is reopened for the next gear?

Ryan

PS. I know that the blow off valve activates under high manifold vacume, but there is still a pressure spike between shifts.

peejay

Absolutely.

moremazda

iTrader: (4)

WOHO!!!!!!!

I am finally starting to understand this thing.

zyounker

Moremazda: damn fine ***


-Zach

rx7passion

oh boy! lets see how long of a list of crap i have on my car

car- 1984 gsl
motor- j-spec 88turbo2 block with 90 turbo running 2x 550s and 2x 1200s stock t2 pump in the tank for right now upgrading to surge tank when get tax refund, regulator a porsche 914 one

exhaust- 80mm downpipe and 80mm prescilencer with apexi N1 muffler to be put together soon!

drivetrain-mazdaspeed 12lb cromoly flywheel with act extreme 6 puck clutch (not working to well) turbo trans fitting in place with a 3" diameter lightweight driveshaft.

controlling everything- wolf 3d with msd 6al and avc-d boost controller.

cooling system stock tall 84 radiator with black magic fan and turbo2 thermostat.

oh and dont forget my magnacore 10mm wires they added atelast 15rwhp


still wont drive right cant select gears while it runs clutch does not fully disengage but otherwise it runs farther than most other people on this board


goal is to get a 60-1 wheel stuffed into my turbo and put down 350rwhp. i would like to run in the 11s and autocross the hell out of it.

MIKE-P-28

iTrader: (1)

Ok I got

85 GSL
Cosmo 13b-RE
Stage 3 87-88 Clutch Assembly
Stage 4 89-91 turbocharger and manifold. Comes with P trim exhaust turbine, 360 thrust package, T04B package, 60-1 compressor wheel. Turbine housing entrance is ported along with a ported wastegate and port matched turbo manifold.
Racing Beat 17# steel flywheel
550 cc (stock) primaries
1600cc Secondaries
Haltech e6k ECU
88 T2 tranny modified
Still deciding on guages and stuff, probally gonna run boost guage where stock clock is.
Run a 2 pillar pod for a EGT, and A/F guages

Various other things, but at any rate I hope for <325rwhp

Sterling

Hey can I play, too?! I'm putting an M-62 Eaton blower on my 12A!
Yaw carb, wich I plan to use with the blower. Headers. Cool old slotted rims.
No stripes or stickers, though.
Anticipate about 225 HP @ 10 psi boost with a massive IC from like a Volvo or something, and water injection on a stockport.

peejay, that was a great post! Thanks!

setzep

What I got:
83 Rx-7 GS
84 -se suspension froont and rear
84 -se gray cloth interior with the 83 dash
90-95 Cosmo 13B-RE
Rice Racing special I/C made for the FB
modified -se oil cooler (-10 AN fittings welded on the ports)
87-88 T2 trans modified to take FB shifter housing
Bosch fuel pump from porche 911 turbo
super-flow muffler

What I need:
ECU
turbo
make a manifold
wastegate
driveshaft
bov
larger secondaries
probably about another $1000 worh of stuff that I can't think of now

moremazda

iTrader: (4)

Why thank you, Zach!
Altough I was just asked to pull it down, it belongs to some one else. Damn the luck huh?

zyounker

I figured it wasn't yours.. but thought i should comment on how nice it was

-Zach