GoingInCircle's

i want to do a full turbo back exhaust and greddy pully kit to get rid of air pump...is there anything i need to do before i just bolt these on?..ie full pump,injectores ect..or will i be ok...please help . your input is respecvted for as i am still lerning about rx7s...oh and its for an fd with intake and pettet v mnt upgrade if that helps anything..thanks and cheers
stephen

Jarsky

your injectors can run up to about an 80-85% duty cycle reliably and i think are good for about 350hp - it really depends on how much boost you're running already on wether injectors/rail & pump need to be upgraded.

other than that the main thing to watch out for is overboost when you free up the exhaust with 3" piping or larger. you should really have a boost gauge fitted already to keep an eye on this. if you do have overboost issues then you're going to need at least a boost controller (if you dont have an aftermarket ecu)

4CN A1R

iTrader: (6)

still running stock twins? do you have any engine management whatsoever?

there are alota factors to consider here

purerx7

iTrader: (61)

You will need to port the waste-gate if your on the stock twins, or add some kind of restriction like a high-flow cat. You will also need a boost controller and some kind of aftermarket management whether it be a PFC or a pettit tuned ecu.

Their is a TON of information on this forum about this, just do a little research and come back if you have any specific questions.

GoingInCircle's

stock twins,stock everything..car has only suspention mods and peter farel [i think thats right] cat back,pettet v mnt ,and k and n twin air filters..thats it as far as far as power

RotaryDreamz

iTrader: (29)

purerx7, basically just summed it all up. Just make sure you do more of your research, or else it can cost you your engine. If you are looking for more boost, then you will need to upgrade quite a few things. And, no your stock injectors will not be able to support 350hp reliably.

4CN A1R

iTrader: (6)

well thats not good...

read up some on moding your car. you could be overboosting and doing internal damage. you need to do something to keep that boost at a controlled level

Jarsky

im running stock sequential turbos, with twin K&N filters and a 2.5" exhaust system from the pre-cat - its already pushing up over 1bar of boost on standard with the mods. i was going to upgrade it the same as you running a 3" downpipe from the turbo to a 3" midpipe with high flow cat, to a 3" catback with 5" muffler.

I probably could do it just fine using my boost controller to stabilise my boost and stop it from running lean, but decided to wait until I have an aftermarket ECU to manage it and not take the risk of killing my engine

4CN A1R

iTrader: (6)

1 bar is over 15psi retard

idk what goes through peoples heads

Jarsky

I know it is....which is why I didn't upgrade my exhaust and wont be until I hook up my boost controller & get my ECU sorted or I'd be pretty certain to blow something since the turbo's arent made to take that sort of pressure and at that sort of PSI im sure it'd be running very lean

4CN A1R

iTrader: (6)

the turbos can handle it. its the ecu that cant compensate for the increase in boost. so it doesnt provide enough fuel and you lean out.

and i didnt mean to be so harsh, i apologize. i just have trouble tolerating stupidity.

Jarsky

yeah I was saying it was the big increase in boost that I was already running which is why I didn't upgrade my exhaust - but in saying that, i can control the duty cycle via my AVC-R so theoretically I can run it without leaning out if my injectors are up to the job - but I would prefer to upgrade my ECU, fuelpumps & injectors first.

Anyway enough of hijacking his thread

KaiFD3S

iTrader: (37)

OMG, what a revelation, nobody has bashed him with a question that has been asked countless times...

Thank you, this makes the forum a good forum once again...

purerx7

iTrader: (61)

I highly doubt you are pushing over 15 psi on stock turbos, ecu, pump and injectors and have a working engine. I swear, sometimes, I feel like people live in fantasy land. Besides the fact, if you had a 2.5" exhaust, that would provide enough restriction to the point where it should not be spiking over 15psi. If somehow you are not over exaggerating, your motor will not last at those 15psi spikes. A boost controller will NOT control boost spikes, only porting your waste-gate can effectively control boost creep/spike.

It is ill-logical posts like these, that people come on here and read, than think they will be fine because you are "supposedly" running over 15psi on stock ecu and fuel. Than when the motor goes POP, people wonder why.

Jarsky

I never said it runs like that all the time - but ever since i fixed my boost leak (had a massive leak and was only running 4.5PSI) its been running anywhere between 12.4PSI > 15.7PSI.

I never said sure go ahead with it, you'll be fine - infact I said I dont want to do it myself because im afraid of popping my engine with a crazy boost creep like that. When I watch the needle jump from 0.8bar to just past 1bar I know it's not good for my engine. I would go take a picture of it for you but i'm currently in the US and my car is back home in a garage jacked up with the gearbox out ready for a new clutch/flywheel/etc...to go in

gracer7-rx7

iTrader: (16)

You need to spend some time reading the FAQ thread

GoingInCircle's

thanks to all, i have read up ,going fuel pump,fuel line[just cause there old],del the air pump,power fc,and gasket kit for motor{profe installed of corse},then i will do full exhaust and 99 spec turbos,thanks again all,i like this site

mrb63083

iTrader: (4)

For the record...

Technically: 1 bar is 14.5037626 psi (http://www.ilpi.com/msds/ref/pressureunits.html)

If you are running a stock ECU, stock injectors, and stock fuel pump on a full 3" exhaust your car will not run good at all. Put a high flow cat on the car, upgrade your fuel pump, and install a boost gauge and make sure you're running no more than 10-12 psi and you're fine.

Now, you can run these lower boost levels with a midpipe, but it would require more modifications. More specifically, with the ECU and fuel. Without these modifications the car will be unpredictable and you will more than likely blow the motor to excess boost. It's hard to control the boost on these cars with a midpipe and stock parts.

However, If you want to increase the boost past the 10-12 area; I'd follow what others have said. Get a Power FC or any tunable ECU, boost controller, fuel pump, and larger secondaries. Also, keep in mind, with higher boost levels one would need an upgraded intercooler as well.

fendamonky

iTrader: (6)

I would *def* avoid removing the restriction provided by your main cat until you've learned a good deal more about the car. It's a recipe for disaster unless supported correctly.

Probably a good idea, 3" free flow exhaust isn't just a plug and play application =) esp not on the stock ECU

Your post made me wonder the same thing...

The stock HT12's are outside of their efficiency range above 15psi, this has been shown time and again. The blades stop compressing the air, instead "chopping" the air, and they begin to produce so much heat it would negate the positive effects of the increased boost. BNRs do not have this same problem. The stock ECU will (is supposed to) hit fuel cut long before 15psi.

And don't be so sure of yourself, especially when you aren't entirely correct.

It's a good idea to keep restriction, to limit boost, in your exhaust system until you have properly supported a free flow system with proper fueling, boost control, and (preferably professional) mapping.

4CN A1R

iTrader: (6)

i am running full exhaust with no problems. the idol needed to be raised to compensate for the lack of air which was previously provided through the airpump. i still have a 10-8-10 pattern...idol is a little higher but nothing to worry about, and boost never exceeds 10psi. period.

i never said they'd be "out of there efficiency range" abover 15psi. but they will still boost up to that lv. they wont have a steady pattern if your running seq. there is a guy on the forum who has been boosting 19psi on stock twins for 2 years. he posted dyno results, track runs, and trap speeds. the evidence is all there.

next time check your sources before you start blabbering.

fendamonky

iTrader: (6)

^ Would you like a cookie?

I'm not going to even bother arguing with you because you'll believe you're right no matter what anybody says, or what facts/experience they may have to back their opinion.

What would you say if I told you I was pushing over 400 rwph @ 17.5psi? You probably wouldn't believe me, huh? I guess it was a fluke that I made 330 (or 322, depending on what type of dyno you'd compare to) at 12psi on stock sequential twins, and stock ports. And making 380 atw (@ 16psi) was purely fictional when I switched to a turbo in it's efficiency range. You've got all the answers right?

Should I even bother to point out the different "power" readings different brand/types of dyno's will show? Doesn't matter right, at the end of the day a number is a number... I suppose you also think that knowing how to launch effectively has no bearing on 1/4 time or E.T., it's all about PSI and dyno power, eh?

Pull your head out of your *** guy.

And fwiw it's spelled "idle" not "idol"


But whatever, you are correct on every point you've made so far (including the correlation between bar and psi, science has it all wrong..) Please forgive the rest of us common folk for ever doubting you.

4CN A1R

iTrader: (6)

^ that was not needed. sent you a pm

mrb63083

iTrader: (4)

I'm not doubting you, I just have never heard of anybody running a full 3" exhaust and not get some type of boost spike or creep.

I ran a full 3" exhaust on my car for a long time with stock ECU and fuel system and never blew my motor. However, I could have very easily. I suppose I got lucky with my boost spikes. I do know that porting the waste gate helps as well. Personally, I hated the boost creep/spikes and ran a high flow cat in the end. Additionally, my car ran better with the high flow cat; restricting the boost creep/spike, keeping it at efficient and safe levels. I did, however, miss the sound of a midpipe.

4CN A1R

iTrader: (6)

since strait answers seem to start conflicts-

highflow cat vs midpipe:
https://www.rx7club.com/showthread.p...ht=boost+creep

wastegate porting:
https://www.rx7club.com/showthread.p...ht=boost+creep

restrictor plates:
https://www.rx7club.com/showthread.p...ht=boost+creep


i understand. i run a boost controller on just the wastegate line to keep the boost under 10psi. cold weather is the only time it gets out of hand. on a cold day in high 3rd, the boost starts to climb over 10psi. so i just avoid cold days altogether.

the midpipe does make the car sound amazing. after the transition, it screams

GoingInCircle's

ok..after looking into it,im doing down pipe,mid pipe with res,high flow cat ,greddy ti cat back,fuel pump,greddy prospec b,turbo timer,ngk wide band,defy boost-egt-fuel presure gauge,mitsumoto rad,samco hoses,greddy twin filter kit