Should I have more than 36psi boost WOT with M4s and stock turbo?
#1
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Should I have more than 36psi boost WOT with M4s and stock turbo?
Now that I've got a nice gripping clutch, I can't blame it for low boost numbers.
I don't WANT more boost, but I also think I may have something awry, and want to know if I should be doing some troubleshooting.
Is that one missing exhaust manifold gasket causing a problem?
I don't WANT more boost, but I also think I may have something awry, and want to know if I should be doing some troubleshooting.
Is that one missing exhaust manifold gasket causing a problem?
#2
Justin,
I'm not sure if the M4's are enough to spin the charger up to 36psi by themsleves. (I don't have my Don M's yet ) RJ probably knows for sure, but with the Smarty on SW #9 it should do so easily.
I wouldn't think that a missing manifold gasket would create a serious loss of boost unless you are getting a very noticeable leak from it.
I'm not sure if the M4's are enough to spin the charger up to 36psi by themsleves. (I don't have my Don M's yet ) RJ probably knows for sure, but with the Smarty on SW #9 it should do so easily.
I wouldn't think that a missing manifold gasket would create a serious loss of boost unless you are getting a very noticeable leak from it.
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no i dont think so...i only pushed high 30's on 100hp sticks and a comp with stock turbo, on a cold night i could spike 42, so with M4's only id think 36 is about right
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#8
I still think that your just throwing to much fuel through it. My buddy ran a comp and mach 4's on his stock turbo and on 5x5 he was literally dumping raw fuel out of the pipe. The truck ran quicker on 2x5 than 5x5 because of the amount of fuel being pushed through it. Just something to think about.
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Originally Posted by Jetpilot
Hohn,
The HX35 does best when limited to around 30 psi boost. Boost above this number only creates heat and decreased HP.
Doug
The HX35 does best when limited to around 30 psi boost. Boost above this number only creates heat and decreased HP.
Doug
Maybe I should try looking at the pyro?
The other thing that's interesting is how you can "feel" how the 35 is out of its league. Stepping on the fuel pedal makes a lot more boost, but not a lot more actual acceleration.
I think a 14 housing wouldn't even begin to do enough to make it worthwhile. I need a turbo with a bigger hot side: SPS62 or such.
Big Blue--
I don't have the wire tapped. Your friend was getting more fuel on 2x5 than I have.
Chriss- You are getting 33-36psi with the EZ boost elbow on, which still allows SOME wastegate function. I have the WG completely disabled (pipe plug), so I should have more than 36psi, right?
As stated before, I know that this setup is not optimal, and the 35 does best under 30psi. I don't WANT more boost-- I'm just thinking this much fuel on the stock charger should make more if everything is sealing.
Maybe not. Maybe it will only make 36psi or so, because drive pressure gets so high so fast once you get well off the map.
The confusing part is that I've made more boost in thinner air with a weaker clutch. How can that be??
I should re-activate the WG, as I suspect I have enough fuel to hurt the stock charger under certain conditions.
#10
I dunno know about it not making more because of drive pressure. I could make my hy hit 40-45psi with a comp and 275's with the wastegate clamped shut. And I KNOW I had more drive pressure with that than you do with an HX.
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Wouldn't a Smarty and M4s be more fuel than a Comp and 275s?
An HX35 isn't THAT much bigger than an HY35 to where it drops DP a ton?
Maybe I just need to order a TST box for "testing" purposes
An HX35 isn't THAT much bigger than an HY35 to where it drops DP a ton?
Maybe I just need to order a TST box for "testing" purposes
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HOHN, I know we arent comparing apples to apples, but my setup with comp off and just the 4's, I can only hit 35psi. Granted not the same turbo. When I had my stock 35 with 4's and comp on 5x5, it would hit alot more than 35(what the gauge at the time went up to). Seemed like it would be in the 40's. Only problem with that setup is that the egt gauge moved faster than the tach.
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Hohn, I can hit 36 psi with Smarty and DD3's... I definitely feel this turbo is overmatched with the Smarty but I won't be getting rid of it until I get bigger sticks and/or TST... I don't want to lose the quick spool of the 35 until I have enough fuel to spin a 62 or 64.
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I took the truck for a spin today with the wastegate disabled completely(turnbuckle).I hit 40 once on 5x5.The funny thing is the last time I drove it I had the wastegate enabled and saw 20 psi max on 5x5,and I think the truck was faster then.I still get smoke at 30ish boost but very minute.I had more smoke of course at 20.What do you think the deal is?The comp is a drag and I was running a downpipe only(waiting on stacks),and me and my buddy had just finished the vulcan big line and I am getting 15idle and 10 wot.Another thing worth mentioning is that the truck is an 01 5 speed and the wastegate is hardlined.Has the turbo been changed to an hy?I was under the impression that this truck was supposed to have an hx.Anyway do you think the problem is that I am creating too much boost for the amount of fuel?I am planning on injectors.Sorry to bust in on your thread HOHN.Any suggestions from anyone would be greatly appreciated.