Too much boost!!! Help!!

Sassan

New Member
May 31, 2010
71
0
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Rialto, California, United States
So I have a 87 turbo targa wit a fresh rebuild with 1700 miles on it. Did a very nice 1500 mile brake-in. I have upgraded intercooler 3in down pipe and 3in exhaust. Engine is slightly built. I have a free ct26 Godspeed turbo (it works -_-). The problem I'm having is I'm hitting fuel cut at 10-11lbs of boost. BUT I dnt even have my boost controller connected. Is there a way to limit my boost 3 or so lbs or Wat can I do to raise my fuel cut level. I can't track my car if I can't go wot without hitting fuel cutoff.
 

radiod

Supramania Contributor
Dec 13, 2007
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Abbotsford, BC
It's not uncommon if you have a very free flowing exhaust and intake to be getting up to fuel cut range. Only real thing you can do is restrict it somehow. Adding a cat will make a small difference, a tail pipe silencer might help as well, but there's not much you can do that is "simple". Being closer to sea level and the cooler winter weather doesn't help either.
 
Sep 19, 2011
510
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Des Moines, IA
Sassan;1899200 said:
So only thing I can really do it get 550 injectors and lex maf at this point huh?

That if you want to have room for a little more power or put the stock downpipe and maybe intake on to lower the boost some, which will also lower the power. Fuel cut is a good thing, but it is such a PITA.
I remember when I first put my exhaust, downpipe, and intake on. The car felt like a monster, then boom fuel cut.
 

planemos

New Member
Apr 22, 2011
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Slocan Park, BC, Canada
You can run a restricting plate at the turbo elbow to downpipe connection. Just get 2 exhaust gaskets for that flange. Then cut a piece of sheetmetal of the same shape and drill the 3 bolt holes. Next get a holesaw and make a 2 inch hole in the center. Put the piece of sheetmetal in between the 2 gaskets and bolt the flange back together. You will be able to experiment with the size of the center hole (make it bigger/smaller). This should keep you from hitting fuel cut until you can get some kind of electronics standalone or whatever in the future. This was my idea that I was going to do with my 2JZ.
 

jonahs_supra

Active Member
May 17, 2011
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Lancaster, Ohio, United States
You checked it when new but now it has some miles on it
I would recheck anyways
Also check for boost leaks
Fuel cut at 10psi is a little low
Then if everything checks out fine there is a few options you can do
1. Fuel cut defender. I do not recommend this without the use of a wideband
2. Lexus afm, 550cc injectors, piggyback and a wideband

3. Piggyback tuner. Again you need a wideband
4. Standalone ecu. Pretty much self explanatory lol
 

Sassan

New Member
May 31, 2010
71
0
0
Rialto, California, United States
Tested it yesterday night n it open fully at 11,12 lbs of pressure. So I think my fuel cut is just set a lil low lol. But also I found out that my intercooler piping that goes from my turbo to my intercooler has a small rip n the plastic tube so is it possible that this boost leak is lowering my fuel cut point??
 

Sassan

New Member
May 31, 2010
71
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0
Rialto, California, United States
I have a wideband. And I just got 550 injectors. Still need Lexus afm. But Wat is a good piggyback? I only want an easy 350 maybe in the distant future 450. N u dnt wanna do standalone cost more than Wat I wanna invest at this point. So Wat a good piggyback?
 

Dan_Gyoba

Turbo Swapper
Aug 9, 2007
1,836
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Alberta
www.gyoba.com
Wikipedia lists Rialto CA as 3,000 ft above sea level, so yeah, I'd say that your FCO is a little early at 10 PSI. If you were lower than 1000 ft above sea level, then that would be closer. Still, at about 10 deg C (50 F) that's not far out of line at all, probably within tolerances for stock injectors.

For 350WHP, the Lexus/550 with an AFPR would probably get you there without a piggyback. I'd probably add an AFPR for gross fuel control, and upgrade the fuel pump to make sure that you don't starve it. A wideband is a good idea if you want to play with that at all. An HKS VPC or APEXi Neo coupled with a 57 trim turbo upgrade and decent exhaust could probably get you to 450.
 

Sassan

New Member
May 31, 2010
71
0
0
Rialto, California, United States
i have a upgraded fuel pump just not installed yet waiting till i get my lex afm. i have a good exhaust and so forth i also have a ct26 that is a 60 trim as well sitting around waiting for well my supporting mods to be put on. i also have a ffim that my friend gave me. worked great wen i took it off his 7m before he crashed it -_- so all i waiting on is a lex afm and a piggyback of some kind
i have:
550 cc injectors
upgraded fuel pump
ct26 60 trim turbo
ffim