QMP Formula Update....780rwhp/850rwtq
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how come everytime you go to the built motor you have so much bad luck with fuel pumps? heheh.
Im trying to decide on what fuel sys to go with on my setup as well.
congrats and good luck!
Im trying to decide on what fuel sys to go with on my setup as well.
congrats and good luck!
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Originally Posted by Y2K_WS6_T/A
Rob,
I didn't do a search, but is this a built 346 c.i. motor?
Mir
I didn't do a search, but is this a built 346 c.i. motor?
Mir
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I took a quick look at the T76 turbo map and at 20 psi, 6000 rpm you are falling off the end of the map. You might want to try my site and use the Turbo Calculator. You can put in the numbers for your car and plot them on several different maps. I recently added some of the newer Garett Ball Bearing GT series maps, more to follow.
It does look like you need to step up to a T88 based on the turbo maps.
It does look like you need to step up to a T88 based on the turbo maps.
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if you're 'out of turbo' why would you go to a smaller exh housing? this is a big engine, it can put it to good use. T76GTQ is a great choice, i don't understand how you don't get any extra power from extra boost. if you have boost in the manifold, but not in the cylinders (providing you're not 'out' on turbo/injectors) then the head might not flow enough, or the cam has too much overlap.
turbo might be too small, but i seriously doubt that, that is a decent size hairdryer, and i've seen it put better numbers than yours on a supra than this.
do you have a dyno chart? does the power drop off at the top? if it drops off a lot on top, it might be losing timing, or fall off the efficiency range so far it's just not flowing enough even though the psi is right. injectors could be out, but you'd see it on a/f graph.
sorry this is kinda messy, but that's just me thinking on 'paper' :/ show me the dyno run and i'll might figure something more out.
my biggest guesses would be new cam ain't so good, if you up the boost and nothing happens, i'd say the extra psi are coming out the rear. take a look at maf flow rate, does it go up along with upped boost?
turbo might be too small, but i seriously doubt that, that is a decent size hairdryer, and i've seen it put better numbers than yours on a supra than this.
do you have a dyno chart? does the power drop off at the top? if it drops off a lot on top, it might be losing timing, or fall off the efficiency range so far it's just not flowing enough even though the psi is right. injectors could be out, but you'd see it on a/f graph.
sorry this is kinda messy, but that's just me thinking on 'paper' :/ show me the dyno run and i'll might figure something more out.
my biggest guesses would be new cam ain't so good, if you up the boost and nothing happens, i'd say the extra psi are coming out the rear. take a look at maf flow rate, does it go up along with upped boost?
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Its most likely related to the downpipe... Even on the almighty Supra
they have to have bigger than 3" to get past these numbers... It could also be an inlet restriction, but usually that would show itself by not being able to make more boost even with the wastegate locked shut.
Is it possible to get a 3.5" downpipe into the car (even if you need some clearance 'dents' it still should do a LOT of good).
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Is it possible to get a 3.5" downpipe into the car (even if you need some clearance 'dents' it still should do a LOT of good).
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Rob, have you given any thought to going with the Precision PT76 GTS? There was a magazine that had at least one Supra that made 980rwhp. I've even heard a couple of rumors that that turbo has pushed over 1000rwhp.
#35
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Originally Posted by Earl H
Rob, have you given any thought to going with the Precision PT76 GTS? There was a magazine that had at least one Supra that made 980rwhp. I've even heard a couple of rumors that that turbo has pushed over 1000rwhp.
I don't believe they make a 76GTS with an on-center housing. FWIW, hp numbers from Supras aren't really comparable to a turbo V8 because they will be operating the turbo at a very high pressure ratio and the turbo is more efficient there.
For example, a Supra may make 900 rwhp with a 3.6 pressure ratio, and the turbo will be operating in the 70-75% efficiency range.
An LS1, which will be moving more lbs/min at a lower pressure ratio, may do 800rwhp with the same turbo with a 2.2 pressure ratio, but the difference is it will only be in the 60% or less efficiency range.
What I'm trying to say is, a turbo that makes "X" amount of HP on a Supra will probably not make as much peak HP on an LS1.
BTW, Rob, congrats on the numbers
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Jim is correct, the GTS does not come in an on-center configuration. But I don't think it would help all that much with Rob's car, since the GTS is only rated about 50hp more then the GTQ.
Jose
Jose
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yep sounds like you maxed out the compressor maps of that turbo, isn't it fun?
Time to go Bigga! Way to go Rob, if i had the money I would've went turbo, o yea and if I had a M6 too.
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