Increasing boost, while eliminating fuel cut.

[anokabball24]

I'd like to go above and beyond 14.7 psi in my '88 Shelby Tona. So far all I have done to the car is a Walbro 255, bov, g-valve, 3-wire O2, and new fuel filter. Everything else is stock.

I'm confident my car can handle the increased boost. I'm not sure how much, but I'm positive it can. A new HG was installed about 6k miles ago, the new fuel filter has 200 miles on it, and everything else seems stout. Not to mention, at stock boost (12 psi I believe) at WOT, the Dawes is reading blue.

My options consist of a new calibration, and 3bar racing fuel cut eliminator.

Are the fuel cut eliminators self explanatory, and do they work all the time? I'd like to go this route because it's the cheapest.

I'm aware that my stock intercooler, and stock exhaust will be bottlenecks. I plan on upgrading those soon.

Any other info would be sweet!

[moparfwdsleeper]

Stay clear of the fuel cutout eliminators. save up and do things more correctly and make the setup safe at the sametime. If your going with a cal from FWD-P then take the instructions they give you or stay away from them as you'll probably end up with issue's and have a crappy running car. Either way a FWD-P or a custom chipped cal i'd recommend a 2 or 3 bar MAP. Going fast cost money, the less you spend now the more you'll wish you would have spent later on.

[overboostperformance]

^+1 on spending money right. i went the route of bleeds to eek out to 14 on my 88. well don't ya know when your brother holds his finger over the bleed hole and keeps opening it then tells you he has his finger on it and lets go. 20psi boost gauge was pinned and motor made a few funny noises. that rebuilt motor made it only to 15-20k when i decided to do this. i now run a FWD cal and love the reliability of it. nothing to fiddle with no making sure the 5th injector is on or the hobbs switch kicks on when it should just watch my egt gauge and my a/f every now and again to make sure everything is OK.

many people on here have done it the "old" way (successfully) before we had vendors that could put out quality cals that are not really outrageaously priced.


Norm

[anokabball24]

Ok, reason I asked is because I wasn't sure whether or not those cut-out eliminators were safe. Thanks for clearing that stuff up.

[detobias]

Quote:

Originally Posted by moparfwdsleeper Either way a FWD-P or a custom chipped cal i'd recommend a 2 or 3 bar MAP. Going fast cost money, the less you spend now the more you'll wish you would have spent later on.

I think sleeper meant he would recommend a 3 bar map, since you already have a 2-bar, and you said you wanted to go above 14.7 psi -which is above the range of a 2-bar

certainly a 3-bar map and custom cal (once optimized, which may take an iteration or two with the vendor) would be the simplest option, most user friendly, but expensive; probably the best solution if you plan to go >18-20 psi

if you dont have the money, like some of us, then you are forced to go old school and play with zeners, 5th injectors, AFPRs for tuning, and/or other tricks.

a zener diode is the *cheapest* cut-out eliminator (I got mine for free) but you have to TUNE SMART: be careful when raising boost, watch your plugs, A/F, EGT, ... works for me but I never go above 15psi and mainly added mine so I could run 13-14 without the occasional aggravating overboost shutdown

[rwboring]

honestly if you have stock injectors and your not raising fuel pressure you cant go much higher... just get a computer from TU, throw +40's in it (you have the fuel pump), and up it!... from my experiences with FWD they depend on fuel pressure... so you could buy an AFPR or just get bigger injectors and have the computer "matched" to your engine... seems much safer to me!