1.3mazda

how do u install a boost gauge and manual boost controller, i am trying to monitor my S5 TII engine, and i want to turn down the boost until i can get around to either getting a FMIC or re-locating the stock RX7 turbo TPIC to the front, any info that would help me out is appericiated and thanx!

87FCTurboII

iTrader: (2)

You can't turn down the boost with a boost controller. All it does is bleed some pressure from the wastegate line which lowers the pressure the wastegate sees. This can only raise the boost.

1.3mazda

is there a way of installing a less stiffer spring in the stock wastegate or BOV for less boost!!!

new with forced induction if u gusy cant tell yet, and i am just trying to decrease my boost capability, 8.3 psi i have been told is the max stock boost for an S5 TII motor, and yes i could crank it up safely to 10-12 psi (at least that is what i am being told), but would rather only to be bossting to about 5-6 psi ONLY!!! any suggestions please and thanx.

hurleysurf24

iTrader: (3)

dont put your foot down so hard on the gas

phoenix7

drive it like a grandma?

this jpeg tells you how to install boost controllers:
As far as boost gauges: I have a "T" nipple on the pressure sensor vaccuum line that goes into the gauge in the cabin.





Hope it helps and search for more details.

WadeMCarter

damn that diagram is so good, the fsm should have used it!

hurleysurf24

iTrader: (3)

isnt that greddys diagram lol

dwb87

iTrader: (22)

There is a HUGE price hike from MBC's (manual boost controllers) and EBC's (electronic boost controllers). Does anyone think an EBC is necessary? There are advantages, but prices are high. So with boost controllers, you can't turn down boost at all?

1.3mazda

so again, is there a way of installing an aftermarket wastgate or less stiffer (spring rate) wastegate spring, or is it the Blow off valve that i should be looking at to lower the stock max. boost (8.3 psi for S5 TII motor)

phoenix7

I really don't know. I always assumed that you could turn the boost down by setting the boost controller to a lower PSI (which meant the wastegate would open earlier). I neever thought about the spring or whether that would affect it. I'm getting a hybrid turbo soon so I won't be able to try until it gets here.

psychotic7

what is your reason for lowering boost? your car is only pushing about 5-6psi in stock trim.....its only when you put an aftermarker exhaust on when you hit 9+.....just curious because it is perfectly safe to run these boost levels, if you have all the cats on your car, i doubt youre even hitting 6psi or youre right at it.

1.3mazda

well only reason i am looking to turn down stock boost is because i dont have ANY cats (thank god) just 3'' as strait back as i can get, so i guess that means the least restrictive exhaust flow i can get without stepping up to 4'' (which is really $$) or no exhaust at all!! and also mainly because I am putting S5 turbo motor in S4 NA chassis, so i dont have a TII hood and dont have the extra $$ for 2'' tubing to relocate the stock TMIC to FMIC!

psychotic7

at least rivet a hood scoop on your stock hood, you can get a fiberglass hood scoop for 100 bucks or less and it will make your TMIC functional and wont be near as expensive as running a FMIC....just a thought so you wont have a big headache and you can run the high psi...so now you have no excuses, haha! BOOST away.

psychotic7

example
http://www.fiberglass-hoods.com/hood-scoops.shtml

1.3mazda

good enough for me, but now what about some JAPANESE S5 TII WIRING DIAGRAMS??? PLEASE AND THANX

MaczPayne

iTrader: (5)

Good luck finding one. The Japanese FSM is a bear to handle, and you better be fluent in Japanese if you want to get anything out of it.

Better use the US version of the FSM: http://208.62.166.66:82/guest/shop_manuals/89-91FSM

1.3mazda

yeah i beleive it was this thread, so can anybody help here??.....
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/need-jspec-wiring-diagrams-s5-tii-fsm-667740/#post7105663