Just added 3'' turbo back and Mbc/hitting fuel cut. Help

[turbonator]

Hello,

This is not my first legacy turbo but first time I've modded one.

I'm hitting 13psi in 3rd and fourth gear and getting fuel cut.

My first question is. Is the car ok with this much boost without a Intercooler? Canadian winter car.

Seconed. My friend who istalled everything can get me a fuel cut defender with rrfpr for $150.

Should I have that installed or go with the DiY FCD?

Thanks.

[cj91legss]

DIY FCD Is plenty fine, i've made several of them and no problems

[Legacy777]

If you don't have a wideband, I'd suggest investing in one. I probably would pass on the RRFPR. If you can make it work, turn your boost down just a tad so you're not hitting fuel cut. The reason I'm suggesting this is because if you do get a FCD, you may be tempted to up the boost even more and with the stock turbo, you're really not gaining much.

[turbonator]

If you don't have a wideband, I'd suggest investing in one. I probably would pass on the RRFPR. If you can make it work, turn your boost down just a tad so you're not hitting fuel cut. The reason I'm suggesting this is because if you do get a FCD, you may be tempted to up the boost even more and with the stock turbo, you're really not gaining much.

I'm really happy with the way it drives right now so I would not be tempted to increase boost untill I do some more mods.

I take it then that the car should be fine around 13psi once I install the FCD.

Thanks.

[Legacy777]

Yeah, it should be alright. One thing you need to watch though is during colder winter temps, your boost will go up due to the colder air being denser. I'm assuming you're using a MBC. If you're using a closed loop EBC, it should maintain boost regardless of ambient temps

[turbonator]

Great answers.Thank you again.


What can the stock fuel system take once I intercool it? 15psi?

This is great car to start learning about all this stuff. I'm going to boost one of my bimmers this summer.

[cj91legss]

i'd just keep it at 13 to be safe

[Apex3]

Great answers.Thank you again.


What can the stock fuel system take once I intercool it? 15psi?

This is great car to start learning about all this stuff. I'm going to boost one of my bimmers this summer.

I'd stick with 13psi until you start upgrading other things, fuel system is pretty easy and cheap to upgrade.

And boosting a BMW is a whole new can of worms, you'll get the basics from the Subaru but I hope you're ready for some rebuilds

[Legacy777]

At around 13-14, depending on intake & exhaust, you're at the limit of what these cars can do. Adding an intercooler simply provides more margin of safety and better power due to denser air. The issue with fuel is that some just stick larger injectors in. The problem with that is the ECU can't properly run those larger injectors. It may "work" but it's not right. Additionally, the MAF sensor is going to be at the end of its usable range.

So to do it right, you would need larger injectors, a MAF with a larger range, and some form of engine management to control fueling.

[Apex3]

I always forget about engine management on these cars. Since I haven't done any engine work to speak of I'm still used to my BMW, where you could pretty much do any mod without any supporting mods

I would suggest engine management though regardless of what psi you end up at