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-   -   Tuning Question (https://www.nopistons.com/3rd-generation-specific-18/tuning-question-61796/)

teamrj83 09-21-2006 10:46 PM

I am adding my 3" exhaust satuday since I got my PFC working. Now when I get rid of my cat and stock downpipe, and run a full 3" system strait to my greddy exhaust. what do i need to change on my PFC to allow me to run it safely?? or is it a lot more complicated than that??



also what kind of boost controller do I need to up my boost on the stock sequential turbos??



I also am installing a large SMIC saturday if that helps also?? I would like to up my boost to 14psi but untill I get injectors I will stay at 10psi, but when i ditch my midpipe and stock downpipe I dont want to destroy my motor and I heard its common on these cars without changing something on the PFC when you get rid of the cat for a strait through midpipe.. Anyone know what i gotta do???!!

amp 09-21-2006 11:40 PM

pfc controls boost just fine imho..

as long as you keep the boost levels at 10psi.. you should be fine with the vanilla pfc map..

even with boost creep of 11psi... not sure if you have your wastegate ported..

dont venture outside of those levels until you get supporting fuel..

watch you inj duties at wot with your current setup as well..

teamrj83 09-22-2006 09:07 AM

yea, I already ahve a walbro 255 fuel pump installed but the rest of the fuel system is stock, I am planning on just installing the mid pipe and down pipe to my greddy exhaust system and calling it a day. I dont have any plans on upping my boost levels yet! so i will not be touching that at all.. boost creep to 11psi should be fine for me tho right?? my turbos are completly stock no porting done whatsoever.. I do have plans on upping my boost as soon as I buy my 1300cc injectors (which I believe are the biggest I can run with a commander) and next week I am installing a large SMIC system and moving my battery to the hatch area..



I just wanted to know if I will be safe for running the midpipe and downpipe on a fairly stock car minus the PFC and exhaust..



also what kind of boost controller do i need to change my boost settings to say 14psi or does my PFC allow me to do that from the commander?? I dont have any plans on doing so till i get my fuel mods but im the type of guy who likes having the parts on hand to do something when I get the itch to go ahead and up my boost..

amp 09-22-2006 10:47 AM

youll be fine with 11psi..

you can run bigger than 1300cc with pfc..

use the commander under settings and boost to increase..

might want to invest some time readin up on the manual.. info is there

teamrj83 09-22-2006 11:06 AM


Originally Posted by amp' post='838102' date='Sep 22 2006, 10:47 AM

youll be fine with 11psi..

you can run bigger than 1300cc with pfc..

use the commander under settings and boost to increase..

might want to invest some time readin up on the manual.. info is there





Thanks amp,



yeah Im reading up on my manual today and while at work when I can, I dont plan on doing my exhaust till tomarrow but still I cant wait to feel my car with an extra 20-30 hp at the wheels :-) NO MORE CAT YAY!!!!!

alberto_mg 09-25-2006 10:11 PM

Be careful with it. My PFC couldn't control boost very well at all. If you can keep it under 11psi, you should be OK, but you can't tell for sure unless you get a wideband on it and check your air-fuel ratios (AFR). A cheap way to find out is get your car to a local dyno that has a wideband and do a couple of runs. I've seen dyno rentals as low as $75 an hour. Just make sure the wideband is working in advance.

black93fd 10-30-2006 12:37 AM

I'm using 1600cc injectors with the powerfc but I had to get new connectors and get them on the wiring harness. But after I bought them I realized they where overkill and I wish I would have gotten the 1300cc even with a t78 setup they would have been fine. Damn I 'm rambling a gain but just don't use the 1600cc

herblenny 10-30-2006 07:02 AM

Let me pass on what I've learned this past weekend.



I took this class called EFI101 (don't take it) for $495 (with discount $420).



Pretty much what I've learned was that if you know the basics and some fancy load bearing dyno, you could tune your car. But the problem is that load bearing dyno's are expensive ($100-175 an hour).



Being that said, full exhaust is necessary to use wideband and you need pfc and datalogit to take advantage of it. If you don't have datalogit, it really doesn't matter..



Stock PFC maps good for upto 12lbs. But the problem is that if you go full exhaust, you will spike. I guarantee it unless you have a ported wastegate. But what some people do is put a pop off valve. Its not the same as BOV. pop off will open up at set psi so that you can't boost pass set psi. Its also called, "engine saver". Its usually not necessary for cars that only boost 10-12lbs but if you were to to run your car to the limit and just in case, its probably a good idea..



Anyhow, what ever you do to your car, ultimately you need good tune and ability to control boost.


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