xCadex

im rebuilding a 2.3T ( ford 2300 engine) and im used to simplicty in garage tunning so forgive my ignorance in rotary tunning.
from the trouble my cousin is having trying to get his plans together for his rx7
i have some general questions to help me help him ,lol

okay first question
1) why is it "unsafe" to run past 10 lbs of boost
can the computer not compensate for the added air and add more fuel?
a.) what is the compression ratio on a 13b
im sure its not high enough to stop from rasing boost
b.) Cut the inital timing if its to unsafe surley you can
change the timing w/o a reburn.. right?
2) what is this about boost spikes from intake and
exhaust mods?
if your spiking do to a less restrictive filter and
exhaust your either running the wrong turbo our your
wastegate is overdue on its scavageing ability

3) just out of curiosty what is the average EGT numbers
on these cars (stock levels)

4) what size injectors do these cars have anyway, max
output level ?

KZ1

1) you coudl prolly run 11 or so, boost control is open loop, that is why.

a) mazda only makes 2 compression level rotors, high and low if you haev 93+ they are low, run up to 30 pis, lol

b) no you cannot , well there are ways, but nevermind, no

2) boost spikes beauty of twin turbo, funciton of twoo much pre-spool on second turbo, so when it comes on you geta spike, this is ofcourse with no boost control,. As mentioned above it is open loop, so car has sets duty onselnoids fo rboost, that is it.

3)no clue, high as ******* hell

4)550 and 850 secondaries. prolly run up to about 13-14 psi, change fuel pressue and go higher, get ECU and change max value of primary and go even higher. plenty of room

rynberg

1. No, the FD uses a MAP sensor and fixed fuel maps. The ecu will fuel cut over 10.7 psi at higher rpms.

a. 9:1

b. You can only change timing with a standalone ecu.

2. The stock wastegate is not closed-loop, it operates on a fixed duty-cycle. It does not accommodate more air flow from mods. A standalone boost controller or ecu is required.

3. That number is so variable due to different sensor mountings, small differences in conditions, etc. Turboed rotaries run hotter than piston engines though.

4. 2 550cc primaries, 2 850cc secondaries

EDIT: KZ1 beat me to it! Welcome back to the forum.

GoRacer

iTrader: (2)

1. No, stock computer does not provide the fuel.
a. Dunno, thought it was 10?
b. Didn't know you could change the timing. The manual says not to.
c. Spiking is from midpipe and creep from ...forgot.
3. dunno
4. 550 primary & 850 secondarys. I beleive 100% duty cycle at 1bar.

http://www.turborx7.com/fuelsystem.htm

http://www.maxcooper.com/rx7/how-to/...tem/calcs.html

xCadex

wow, i see why a new ecu is needed
fuel tables suck!

so for both turbos is there a sperate exhaust runner for both or is it one large runner
same goes for wastegate?

makes sense on the boost creep and open loop what the hell was mazda thinking?


well thanks for the help guys, its rare to actually get replys with out dicks popping in (so far, not from here )

GoRacer

iTrader: (2)

Both turbos are attached to one turbo assembly housing (is that what you call runner?) and share one wastegate.

http://www.turborx7.com/
http://www.robrobinette.com/
http://www.rotaryengineillustrated.com/
http://www.scuderiaciriani.com/rx7/how-to.html

xCadex

yea thats what i WOULD call a runner, lol
how weird 2 turbos, but not really
i got to admit for a piston guy i still am overwhelmed by the charm of these cars.
tunning sucks though
btw thanks for the links ill check them out!