boost dilemma....

[Fox]

hey i have a 87' 929 2.0l turbo and was looking to increase boost but first i have some questions you guys would be best suited to answer..

its running 9-11 psi atm, ( not intercooled ) and i was looking to increase this to 14 odd psi, and my questions were,

will the stock engine take it? (if not wat will need to b done)
will 14 "require" an intercooler, and if so where would i go to get the piping done, as this model never had an intercooler theres no piping kits. ( plenty of space in front of the radiator for a big FMIC tho )
what power increase am i to expect? (have heard 1psi = 10hp)

and insight would be very helpfull.
Fox.

[Twe12ve]

also be budgeting for a retune and management system dude - also, do you have the fuel pump for it? and CAI? and injectors if necessary -also is the AFM up to the task..

u cant just jump boost to 14psi on a turbo without the supporting mods. also, is the stock turbo ceramic or BB?

[Fox]

whats the price on a retune and management system?
no aftermarket fuel pump, no aftermarket injectors, got pod (great for early boost spool :D)

no idea wether the trubo is ceramic or ball bearing, probly ceramic, also wanting to kno wat turbo's will fit on this car?

and if 14 is to much, IS there a "safe" pressure for the stocko? or is it the 10ish it is now?

thanx

[Twe12ve]

man i dont know what management system you would run...i have no idea what turbos you will use..seems to be all custom jobs to me which seems expensive...

10 should be fine..but u need a cooler man..

[Jazza]

If it didnt come with a cooler i wouldn't raise boost in the slightest coz it'll detonate pretty easily.
Get management (call a workshop), fuel pump, exhaust and intercooler and tune it to 14psi if you want some more hp safely!

[Fox]

how much is "management" and when you say this are you talking about engine management, like a new ecu and sh*t? cos that sh*ts hella expensive hey, and im on a tightass budget :P

[Furious2Boost]

Yeh dude, look the 929 wasn't designed to handle much more than the factory boost, Has urs got a boost controller or bleed valve?? im pretty sure the 929 1987 models are non existent, im aware that the 929 had turbo models 1n 1986 and they are 2.0L V6 and like urs they aren't intercooled. Was yours factory or was it turbo upgraded. Correct me if im wrong but to prove my point her is a link to the mazda models and specs
http://www.carfolio.com/specifications/models/?man=3808&Mazda
K mate in answer to ur questions yes get it intercooled as u will cook ur turbo, by upping the boost u will also put a bit of extra stress on ur engine as they are old engines. im not too sure bout how much it will cost to get it intercooled but a full intercooler kit like one designed for a 300zx may fit or if there is room maybe a factory top mount or side mount off a car like a silvia may be able made to fit?? You will also need 'yes' engine management as more fuel and air is going to be running through ur system and ur stock system prolly wont handle the changes too well. As JAZZA08 specified the engine management is an ECU so something like an APEXi, Blitz or summin could do the trick. All up dude u are going to be looking at some mone being spent if you are going to do it the right/safe way but if you arent to phased with it (the car) add a couple of psi and get a small stock intercooler popped on. Hope this helps dude.

[Fox]

im fairly shure its all factory

http://www.mazda.com.au/pastModelsDetails.asp?articleZoneID=54

(bottom one)

fairly shure its stock turbo, and no boost controller or bleed valve,i may do a decent intercooler job and go 1-2 more psi, but its becomeing evident that without major changes i.e. ecu, injectors, overbore, cam, or even recon, im not gunna be able to do it all as cheaply as i wanna :P as what ive jsut mentioned will be 3k+ easy

[Furious2Boost]

yeh if u get all new aftermarket stuff it will cost u bout 3K but u could easily throw on a boost tap that will cost u like 45 Bucks from Jshop if u already have a boost guage then u dont need to worry bout that. Intercooler... well if u get one of those kits (china kit) or the Monza kits i know from experience are actually not that bad for about $600 just a matter of which one will fit ur 929, an ECU you can find on the forsale forums on here, Silviawa or SAUWA for around $700 - 1K. So your looking at around 2K for good parts. Then you can worry bout ur fitting, coz u can do most of it urself if you know what ur doing, otherwise around $600 to get them fitted so all up u could expect around $2500 new parts and fitted.

[SLEEKA]

ECU?injectors?fuel pump?? honestly i wouldnt bother... Car manufactures ALWAYS give somesort of extra precautions to help their cars last longer. Thats why they always make the injectors, fuel pump or ecu handle that extra bit of load that it would normally encounter just for this reason, a stock turbo car injectors are generally no way near their max duty cycle on stock boost. Some manufactures give more room than others but essentially they all have a little room for improvement in stock form.

One question for you, if you put standard unleaded, not ultimate or premium, in your car and you take off hard on a hotish day does the car ping/detonate?? If it does, dont bother raising boost and start running premium fuel or say good-bye to your motor and a large chunk of your cash.
Now, if it doesnt ping i'd say you'd be safe to pump that extra few psi as long as you run ultimate 98 and if you want to be really safe run higher boost only at night. While a FMIC would be good to help lower the intake charge temps, because as you raise boost = creates more friction = higher intake temps = higher chance of detonation. As long as you run good fuel, boost up at night or colder days and the second you hear pinging you back off and lower the boost straight away you should be safe. You could also try to drop the ignition timing a few degrees if you have a distributor setup (most likely for the era) to further help detonation. Most factory ECU have a boost cut, which means as soon as it detects a certain level, normally a few psi above the stock level, it cuts the motor out to "protect" it, kinda like a rev limiter. If this happens just drop the boost down until it doesnt do it anymore. It might thorw an error code and put the car into a safe limp mode, just disconnect the negative side of you battery overnight and it normally clears the ecu, problem solved.

So what i would do if i was you, and these are MUSTS:
*get a boost gauge, the cheapest i would go is splitfire but i would prefer a autometer as a minimum(most of the guys here sell good second handed autometer or blitz gauges for 70-80bucks)
*bleed valve, once again the cheaper brands aren't as good and a minimum would be a standard turbosmart t-style bleed valve ($100)
*a tank of BP's finest
IF it starts pinging then i would leave it at stock boost until you can afford:
*FMIC
*dyno time to see if injectors are maxed out
Honestly once you've cranked that little bit more into that motor it will bring a smile to your face, BUT just remember after all of this, the motor is old, the turbo is old, you are going to put out more hp which = more strain = more wear and tear = shorter life span for your car SO at the end of the day unless you can afford to rebuild a broken motor or turbo or both DONT DO IT, unless you like public transport and get told you a useless loser with out a car by people like me while you wait for your bus lol

Anyway good luck....yes im done now :boink:

[Fox]

already ahve boost gauge, and run premium all the time, 98 sometimes, NEVER regular, no pings at all ever so far, runs great loves up the boost, hits 8-9 in 1st, 2nd, 9-10 in 3rd and 10-11 in 4th and 5th, iunno why it increases the boost depending on the gear but a boost tap would let me set it at 10-11 and be done wit it, hitting peak in every gear and getting there faster.

where in perth do i get it dyno'ed???

and im definatly doing a big FMIC in forseeable futur

[SLEEKA]

already ahve boost gauge, and run premium all the time, 98 sometimes, NEVER regular, no pings at all ever so far, runs great loves up the boost, hits 8-9 in 1st, 2nd, 9-10 in 3rd and 10-11 in 4th and 5th, iunno why it increases the boost depending on the gear but a boost tap would let me set it at 10-11 and be done wit it, hitting peak in every gear and getting there faster.

where in perth do i get it dyno'ed???

and im definatly doing a big FMIC in forseeable futur
Boost in related to load, so the more load you put the car under the more boost you can hit upto what your wastegate actuator is set at, which would be the 10-11psi mark by the sounds of things. Just make sure when you first install the boost controller to set it to fully closed or full negative boost so your car will only be at stock boost, then turn the tap a few clicks then see what boost your running, then pull over, raise it some more and so on until you hit what boost you want it at. When you test to see what boost your at try and load the car up as much as possible, ie do a third gear pull from like 40kmhr, that way you wont get any suprises. Also this sounds like a stupid thing to say but i've seen it happen to many times... make sure you put the bleed valve in the correct way, putting it in back to front will make your turbo run on open boost (max possible boost it can do) and could lead to some crying on your part.

Theres quite a few dynos in perth, some of the more popular tuners are places like overboost, hyperdrive, etc... i got mine done at tim slakos west racing in osborne park. All you really want them to do is a dyno pull with a wide band sensor in your exhaust to measure if your car shows signs of leaning out and they will let you know what the safe limits are... :fingers: Do a before and after dyno run and see what extra power you make and post it up, should be interesting :lol:

[Nemi]

what's the frikken point its gonna pop quicker than a 89 ****ter gtr.

[SLEEKA]

what's the frikken point its gonna pop quicker than a 89 ****ter gtr.
why is it gonna pop? cause a few extra psi is gonna make it detonate?? If it doesnt ping now on 11psi on a hot day, running 14psi on a cold night should be safe and if it starts pinging theres a simple fix, turn the boost down. The only thing i would worry about is the near on 20year old head gasket, but a well maintained engine should be alright. Whats the Point??? Why do we boost up our cars? More performance and FUN

[Nemi]

coz its near 20 years old and you pushing more boost into it.
turning up the boost reduces the life of an engine turning up the boost on a 20 year olod engine....... if you can't connect the dots here you may want to opt in for a darwin award.

[Onijin]

Has the motor has been rebuilt or reconditioned sometime in the near past? That'd be something else to take into consideration.

[SLEEKA]

BUT just remember after all of this, the motor is old, the turbo is old, you are going to put out more hp which = more strain = more wear and tear = shorter life span for your car SO at the end of the day unless you can afford to rebuild a broken motor or turbo or both DONT DO IT, unless you like public transport and get told you a useless loser with out a car by people like me while you wait for your bus lol

Anyway good luck....yes im done now :boink:
AND thats why i said that.... i was always pretty good at dot to dot as a kid

[Fox]

then ill set my sights on mods for the engine instead of focusing on the turbo, as anything i do will have greater gains cos of the turbo anyway. wat i need now is a helpful list of *usefull mods and what they cost, and where to get em. i figure you guys know best.

i.e: Catback zorst ; 100-500$
Pod filter ; 20-200$+
keeping in mind ive done pod and catback

*usefull as in more powa.

[SLEEKA]

then ill set my sights on mods for the engine instead of focusing on the turbo, as anything i do will have greater gains cos of the turbo anyway. wat i need now is a helpful list of *usefull mods and what they cost, and where to get em. i figure you guys know best.

i.e: Catback zorst ; 100-500$
Pod filter ; 20-200$+
keeping in mind ive done pod and catback

*usefull as in more powa.
*Dump back 2 1/2inch (costly as it will be custom but this is where the gains are) 400ish
*hi flow cat or just drop it out all together (you'll have to get a dodgy exhaust place to remove it though) 50 to 300
*pod, try and make a custom cold air intake, you could probably do this at home (supercheap sell monza flexible piping for like 30 bucks)
*FMIC, probably too costly to out weigh its benefits at stock boost 800ish (custom piping)
*If you were definately keeping it at stock boost, and it doesnt ping, you could pump the ignition timing up a few degrees (use a timing light - free)

None of these things will come close performance wise to a few extra pounds of boost :)

[Fox]

looks like itl be turbo back 2.5, no cat and a 450x300x76 FMIC (core size) all up, given i hand them an intercooler it should cost under a grand at mettams morley :P, then maybe 11-12 psi if its all sweet as.

i think at least till i can do major enginework, this will gimmie some more power to play with.

[Smoked]

i had a mitsubishi cordia gsr, 1.8 litre 4g62turbo motor in it, and one day the vacuum hose split between the actuator and the turbo, so it spun up to like 16 pounds unintercooled and hit the factory ecu boost cut. it was unintercooled, and it was a hot day, i did it all day long until i fixed the hose without hurting anything. once the hose was fixed it went back to 10-11 pounds, i was tempted to turn it back up lol. keep in mind i had 850cc injectors and a hi flow maf sensor, AB model ecu and 2.5 exhaust. stock internals and turbo handled 16 pounds for a day without injury