matty

been running 15psi for 5 yrs now. for some reason when i turn up to boost on my power fc the car doesnt make anymore boost. even when the car had only 20k miles on it it wouldnt make more then 15psi so point is i doubt the reason is because something is tired. any idea why? can i have a leak somewhere?

BigJim

i dont believe the stock turbos are capable of more than 15 psi. I may be wrong so more will chime in soon. But yea get some bnr stage 3's

tom94RX-7

iTrader: (5)

No I know for sure they make at least 20, of course you need the Power FC, fuel system, better IC and wideband to make sure you don't run lean.

DaleClark

iTrader: (55)

You're probably WAY out of the range of what the stock boost control setup that the PFC is controlling can do. A real boost controller would likely be necessary.

That said, running more than 15 psi on the stock twins is possible, but they won't last long. You're overspinning the hell out of them at that point.

Dale

tom94RX-7

iTrader: (5)

You probably should to a boost leak test to make sure. I have never done one on mine though.

matty

bnrs are a waste of money. sorry, i just call a spade a spade.

the stockers go over 15psi. mine just dont for soem reason....only when very very cold weather.

tom94RX-7

iTrader: (5)

Definately try a different boost controller, if you have the fuel system for more boost.

I've been running around 17-19 psi for about a year now, probably close to 100 passes down the drag strip. My times are only getting better, not worse, turbos are not getting tired. I understand someday they will though, but I'm impressed with them so far.

matty

i hear ya,...and agree. 15psi would be my everyday setting. 18/19psi would be at drag strip once a yr and once in awhile on the street. but anyways i want them to go....i have been trying to kill this car forwhile now. i need to be forced to upgrade to single with bridge. for some reason i just cant tear apart a good running car/

can anyone recommend a good boost controller for that will push my stock twins past 15psi.

matty

i really doubt i have a leak..15psi is held rock solid. i bet it would bleed off if i had a leak. i am gonna replace my pcv soon. its original. it should probably be replace....i may be losing alittle boost thru there...i hear its posible.

matty

i ahve the fuel..supra pump with 1300cc injectors. thats plenty for that power level. damn i need to work this out.

matty

would love to see some of the old schoolers chime in and post how they wrere able to generate that much boost

tom94RX-7

iTrader: (5)

Any of those Greddy boost controllers should do it, I like my profec b-spec 2 because it tells you the max boost as soon as you let off the gas, and it stores it to read later. Just read and understand the manual, it can be confusing, but it's worth it, I would buy it again. Before that I made some manual valves from Home depot, they worked okay if I remember correctly, you could try one of those, or read more about them. I still use a Home depot valve for the 2nd turbo pre spool or what ever it's called.

tom94RX-7

iTrader: (5)

And the greddys like mine are nice cause you can have that low and high boost settings, just one push of a button for high boost! I was racing a neon srt, started out right next to him on the low boost, wasn't pulling him hard enough, hit the button for high boost 18 psi and blasted away from him!

t-von

iTrader: (8)

Matty the physics behind the twins compressor size wont allow for over 15psi on a 13b for long periods of time (especially if your ported). As Dale Clark already said your asking too much of them. That's like asking for the stock single turbo in a 2nd gen to be abe to provide a consistant 20psi. Turbos by design can only move so much air depending on their size. Perfect example.....

Try to put a turbo that flows exactly the same as the stock twins on a 8.0 liter viper v10. How many pounds of boost do you think that turbo would produce on such a large engine at 5k? My guess is the engine will be in vacuum, however you would get a **** load of boost/torque up to 3k with the turbo falling flat on it's face because now the larger engine starts to out flow the compressor. This is why you get more hp with less boost when you port rotary's. Your just lowering some of the restriction and allowing the engine to breath better. Bottom line, you want more power, you need more air volume.

tom94RX-7

iTrader: (5)

But you can run 18 psi for a long enough period of time when you want it, like I have been doing on the strip and street for a long time. . No porting done.

GoodfellaFD3S

iTrader: (213)

Sure, 125 mph traps for $2350 is a waste of money

tom94RX-7

iTrader: (5)

I've been thinking about buying the bnr stage 3s. But I don't know if it would be worth the money for me personally if I am already at 122 mph, I'll do 123 next time when I don't spin the back tires for 2 seconds after switching into 2nd gear.

FD3S2005

iTrader: (11)

Goodfella i know you had the bnr's did you think they were a waste of money.. even on non seq?

GoodfellaFD3S

iTrader: (213)

If I had to do it over again I'd keep them seq. Definitely not a waste of money. I'm not a drag racer, it was nice to run them on the street at 19 psi, and make pull after pull on the highway and see my intake and water temps stay in check. I also ran them at 15 psi on the road course in the Texas summer with zero issues. They're 20% larger than the HT12s, and make less heat at the higher boost levels.

rajeevx7

iTrader: (11)

It has nothing to do with boost control. Do a leak check first. Good? Then you are obviously being restricted somewhere. Reconsider all of your breathing and exhaust mods. Then, port the wastegate to be able to accurately control the boost with ANY boost controller.... INCLUDING AN $8 Home Depot MBC.

An unrestricted turbo will spin off the face of the planet.

tom94RX-7

iTrader: (5)

I think there is a chance it has to do with the boost control, although you could be right.

matty, did you get rid of the stock intercooler and the cat? I assume you did get rid of the stock IC, you probably need to get rid of the stock cat if you still have that.

I have a full exhaust with a resonated mid pipe (high flow muffler welded into mid pipe), and I never ported the wastegate and I don't have any problems controlling the high boost levels. Maybe you only need to port the wastegate to keep the boost levels low, I'm not sure.

teamrj83

so youve been running these twins at 15psi for a long time.. I may be wrong but ive read countless posts that they wont last long at that boost level... not flaming just curious, has the rules changed?? if so I want to run my non sequential twins at 16-17psi!! since i dont drive it much anyways but maybe 5000 miles a year max!! with no drag strip use why not??!!

tom94RX-7

iTrader: (5)

I have been for 1-2 years, and countless runs at the drag strip. If you got a Power FC, fuel system (850s and 1600s), FMIC, wideband to tune AFR yourself so you don't run lean, and maybe some more mods I'm not thinking of, then I guess your good to go like me. you can run 16-17 on stock map sensor too. Oh and I only run 93 pump gas too (too bad they got rid of 94 at the local Sunocos), but I just ordered a AEM water/methanol injection kit for safety and hopefully a little more power. 105k miles

FD3S2005

iTrader: (11)

humm you were making 400hp but what ports did you have Race ports?

dgeesaman

iTrader: (7)

First, you'll need an aftermarket boost controller.

Second, you'll probably have secondary/transition problems unless you have a pressure regulator on the pressure tank. More than 10psi tends to make the turbo control pressure solenoid stick.

Dave