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Old 10-03-2014, 11:35 PM   #1
mod maniac
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Default 2.34 smallest turbo that will pull 9k?

I am not looking for the most power (well that's a first). I need the smallest turbo that will still be pulling at 9k on a 2.34. This will be a street car and still do some track time. Just looking for ideas.
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Old 10-04-2014, 02:44 AM   #2
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i wanna see the vid of this one....
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Old 10-04-2014, 02:53 AM   #3
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Quote:
Originally Posted by mod maniac View Post
I am not looking for the most power (well that's a first). I need the smallest turbo that will still be pulling at 9k on a 2.34. This will be a street car and still do some track time. Just looking for ideas.
http://www.turbos.bwauto.com/aftermarket/matchbot.aspx
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Old 10-04-2014, 07:03 AM   #4
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Hint: it ain't a stock location FP Green
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Old 10-04-2014, 08:56 AM   #5
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Rotated 35r or larger.

Seriously.
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Old 10-04-2014, 10:51 AM   #6
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Bigger than 35r...plots posted with 35r start falling off passed 8500

There's plenty of info on this subject I'd do some more research
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Old 10-04-2014, 11:06 AM   #7
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Quote:
Originally Posted by A-man07 View Post
Hint: it ain't a stock location FP Green


I am aware of that but that is the biggest I have right now. I am looking to trade up though. I have four good turbos and none are big enough.
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Old 10-04-2014, 11:10 AM   #8
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Can you better elaborate what it means to "pull 9k"?

Any build will fall off that high without some major head work, regardless of turbo.
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Old 10-04-2014, 11:18 AM   #9
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Can you better elaborate what it means to "pull 9k"?

Any build will fall off that high without some major head work, regardless of turbo.

I have read that a lot however we have had the heads on the flow bench and my tech says they will be fine with just 1mm+ valves, bowl work and port matching. We are also running 280 cams.

What I mean by pull 9k is it will be tuned that high and it may end up there on launch or in second where that stuff happens fast but most of the time it will run where it pulls best which will be up there some where on the short stroke.
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Old 10-04-2014, 08:34 PM   #10
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Quote:
Originally Posted by Uncle Scotty View Post
i wanna see the vid of this one....



I hope to get some good vids when it is done but here is a pic of the car. My last build did an 11.75 in the 1/4 so we hope to improve on that.
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Old 10-04-2014, 08:39 PM   #11
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Dat wheel color doe
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Old 10-04-2014, 09:52 PM   #12
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Turbo mike and bamofo had those low compression destrokes with 40r and they seem to hold power pretty close to 9k. I recently helped a friend build a 2.34 with stock lenght rods and high compression pistons which worked out to be 7.6:1 compression on a 35r and anything over 27psi it seemed to blow hot air couldnt make any more power. That was reved to 8700. I'm guessing it was over spinning the turbo up there but that's just guessing. I would have to say on a proper compression ratio a 35r should do well.
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Old 10-04-2014, 10:01 PM   #13
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Quote:
Originally Posted by mod maniac View Post



I hope to get some good vids when it is done but here is a pic of the car. My last build did an 11.75 in the 1/4 so we hope to improve on that.
I don't think spinnin one of these to 9k is the answer
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Old 10-04-2014, 10:54 PM   #14
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Quote:
Originally Posted by Uncle Scotty View Post
I don't think spinnin one of these to 9k is the answer
Well Scotty my friend we will see.
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Old 10-04-2014, 11:00 PM   #15
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Best bet is to call a company like blouch amd see what they say.

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Old 10-05-2014, 01:50 AM   #16
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Try a gtx 3582

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Old 10-05-2014, 02:22 AM   #17
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Try mapping the compressor with matchbot and eliminate all guessing. Just looking at it briefly, it looks like something around 60lb/min is what you're going to be looking at around 9k. Most 35R's are ~75lb/min


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Old 10-05-2014, 10:18 AM   #18
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You are looking at 35r sized (or bigger) no matter what. Our Shop car has s300 fmw on a 2.34 and it runs out of puff by 8k-8200

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Old 10-05-2014, 04:50 PM   #19
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It's an interesting question because holding power is relative.
Holding power at what boost? You want something that holds a flat 14 psi to red line and it doesn't have to be 35r sized.
Subaru guys are so used to big boost spikes with a lot of taper that they don't realize that's not a typical way to set boost on most other engines. These 2.5 subarus with our tiny cams and large valve angle combined with crappy bore/stroke and rod/stroke ratios get very efficient around 4k and then very inefficient over 6k.

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Old 10-05-2014, 06:15 PM   #20
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like a good tuner told me(insane speed) boost is only air your engine is not using...
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Old 10-05-2014, 09:39 PM   #21
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I don't get it.



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Old 10-05-2014, 10:03 PM   #22
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Quote:
Originally Posted by MPS-Dom View Post
I don't get it.



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yeah....WUT???

and the only thing goin to 9k does is wear things out (much)faster...

these motors are not screamers...
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Old 10-05-2014, 10:18 PM   #23
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Wear wise, these engines are better than many others at 9k. In general, Shorter strokes mean slower piston speeds. However, the fact remains (with any engine) the higher you rev an engine the faster it wears out.

I'm uncertain if he is saying that boost is a function of back pressure. Which is true. Or if he is saying that you should run as much boost as possible all the time. .. which is not true.

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Old 10-05-2014, 10:20 PM   #24
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I was running my 2.1 on a bloch 2.5 xtr with kelford 199-e cams and meth. It had a 6 spd trans. When it would spool up in 1st and 2nd it would happen so fast that it would be in the rev limiter all the time. So we tuned it out to 8k and it was fine. That doesn't mean we ran it to 8k all the time but it did pull it fine. Just hoping for something similar but better. I don't want to go bigger than needed, just big enough. Looking for wide torque curve.
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Old 10-05-2014, 11:39 PM   #25
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Quote:
Originally Posted by ResidentR View Post

Any build will fall off that high without some major head work, regardless of turbo.
Not true at all...



Op, at least a 35r+ sized turbo, probably a 6466 or + a few mm's or so, as ZeeBiker said. A lot depends on what fuel you use, too.
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