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Discussion Starter #1
i have a 91 i/c and im only gettin 10-12psi. . . is that low? i thought it should be like 18-20psi? i put a new air filter on it thought that would help but it didnt???? any ideas?:banghead:
 

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Along these same lines, what would a non i/c truck usually run. My new (to me) truck will peg out the 35 psi boost gauge pretty dang fast if i stick my foot in it in fourth of fifth gear.
 

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Mine usually tops out at 33-ish. I have an automatic though and haven't really pegged her out. This is empty not pulling anything.
 

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Along these same lines, what would a non i/c truck usually run. My new (to me) truck will peg out the 35 psi boost gauge pretty dang fast if i stick my foot in it in fourth of fifth gear.
i could get 18 psi max out of mine when bone stock
 

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Yeah, I should mention that my number is based on my pump being all tweaked. I didn't have a boost gauge installed while she was stock.
 

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Discussion Starter #7
ok good i thought somethin was wrong. thanks for the info
 

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thats normal for a stock 91.5 with the 21cm exh. housing.
 

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Discussion Starter #9
how much boost do you think i would get if i put a 16cm exh. housing on it? or what would be a good turbo to put on it? i was thinkin more of the 16cm housing cuz its cheap and money is hard to come by now a days
 

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my 93 runs 15 psi of boost bone bone stock
 

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10-12 is low. Check your lift pump output. If the pump isnt working as it should, or your filter is clogged, the injector pump cant flow the fuel it needs to in order to make the power and boost.

Stock on most of mine has been in the middle-upper teens.

Dan
 

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I would'nt consider a 16cm cheap, find a used 12cm and put that one there if you don't plan alot of fuel mods in the future, it'll be a little restrictive on the top end if you add too much fuel or if you tow heavy but it will be very responsive through town and stuff, Won't even be the same truck.

If you plan more fuel and you tow heavy then i'd go with the 16cm. you'll love either one over a 21cm
 

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that does sound low for a stock intercooled truck. I could hit 18 psi topped out when my truck was stock, 15 psi on average, i only got up to 18 sometimes. But now with my pump cranked up, i can hit 24 lbs and i have the stock turbo with the 21 cm housing. Check for a boost leak. Have you messed with your pump at all?
 

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Discussion Starter #14
that does sound low for a stock intercooled truck. I could hit 18 psi topped out when my truck was stock, 15 psi on average, i only got up to 18 sometimes. But now with my pump cranked up, i can hit 24 lbs and i have the stock turbo with the 21 cm housing. Check for a boost leak. Have you messed with your pump at all?
yea i have 3 turns on the smoke screw and 3 turns on the star wheel
 

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Discussion Starter #15
I would'nt consider a 16cm cheap, find a used 12cm and put that one there if you don't plan alot of fuel mods in the future, it'll be a little restrictive on the top end if you add too much fuel or if you tow heavy but it will be very responsive through town and stuff, Won't even be the same truck.

If you plan more fuel and you tow heavy then i'd go with the 16cm. you'll love either one over a 21cm
i have a 12cm sittin on my toolbox but i was told not to put it on cuz it would be to restrictive and my egts would go way up?? i was goin to put it on there just to see what it would do. maybe ill to that tomorrow just for the hell of it:headbang: i thought you could get a 16cm for like $180?:confused013:
 

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i put a 12cm housing on my 92 and it spools fast, dropped my egt's about 100 degrees at wot, and gave me about 4 lbs more boost. i think where it gets restrictive is while towing, i have not towed anything with my pickup since i put it on.
 

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If thats a wastegated 12cm housing then as soon as you read this get your butt outside and put that thing on!:truck:

It will spool much better, should have you running around 8-10 psi of boost on the freeway, you can dial the wastegate in to make however much boost you need, but remember, only allow as much boost as you need to keep it cool. 45psi of boost is not always a good thing. with your set up I think if the wastegate is set about 25-28 you should have no issues with heat.
 

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Discussion Starter #18
If thats a wastegated 12cm housing then as soon as you read this get your butt outside and put that thing on!:truck:

It will spool much better, should have you running around 8-10 psi of boost on the freeway, you can dial the wastegate in to make however much boost you need, but remember, only allow as much boost as you need to keep it cool. 45psi of boost is not always a good thing. with your set up I think if the wastegate is set about 25-28 you should have no issues with heat.
i would be out there puttin it on right now but the girlfriend is down for the weekend so the truck will just have to wait :whip: how can i dial in the wastegate?
 

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i would be out there puttin it on right now but the girlfriend is down for the weekend
Well, then you have a tool runner!:hehe:


You can adjust the wastegate rod for the boost you want. If it hasn't been messed with then I would expect you to get 20-25 lbs out of it as it sits. Mine makes 28 and I haven't adjusted it for more as my EGTs are well in check for now . . . .
 

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Discussion Starter #20
Well, then you have a tool runner!:hehe:


You can adjust the wastegate rod for the boost you want. If it hasn't been messed with then I would expect you to get 20-25 lbs out of it as it sits. Mine makes 28 and I haven't adjusted it for more as my EGTs are well in check for now . . . .
a tool runner HA i wish it worked that way. she went back home today so its goin on this mornin when i get up. ill let you know how it turns out. thanks for the info
 
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