Originally Posted by TeamRX8 (Post 4704050)

I feel like you still don't fully get the AR vs turbine design vs engine requirement relationship

it's not just a 1.05, it's a T4 1.05, which is not the same as a T3 1.05. I can't see a 500+hp 2-rotor engine having sufficient wastegate control through the restricted siamese center port, but maybe I'm wrong..

Originally Posted by TeamRX8 (Post 4704050)

As you eluded to earlier, a T3 1.06 with a GT3582R is a known quantity. You won't have any real issues and should hit your goal fine *assuming* the 3rd-port wastegate deal works. That doesn't mean it couldn't have been improved on with a different compressor wheel and turbine housing. You are already risking on the manifold setup so it was reasonable to play it safe otherwise.

Originally Posted by TeamRX8 (Post 4704050)

as for an EFR 7670, more than a few highly experienced turbo gurus think it's perfectly acceptable for up to 400 rwhp 2-rotor application. Their reasoning is that for a street/autox application the low rpm boost response is superior to the 8374 and they aren't running continuous WOT for long periods of time. As always, the right configuration and tune matters.
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Originally Posted by hoss -05 (Post 4704132)

Sorry im trying to get things straight in my head. Mark, Brett are we comparing a borgwarner EFR series turbos to any Garrett? They are not directly comparable in turbine and compressor size alone. the EFR is much longer and its vanes extend much further out, making the comparison in diameter terms of little consequence.

Originally Posted by hoss -05 (Post 4704143)

Than i guess i don't understand the comparison. I know many turbos such as anything with a tial housing/billet compressor or elongated EFR wheel type turbine/compressor will skew the results. I keep seeing direct comparison measurements of actual size, when in the real world they are not the same, all are a give and take. truthfully a more axial EFR type turbine paired with a slightly more efficient larger compressor would be ideal but that simply does not exist in the real world.

Originally Posted by TeamRX8 (Post 4704159)

Turblown promotes the EFR 7670 regularly, just depends on the goal. It's not just Turblown either, but since you specifically used them

I understand the 8374 .92 is a T4. It works because it's .92. My earlier comparison was WRT the well known GT3582R T3 1.06 combination. Because a T3 1.06 maintains a higher velocity it works. The T4 1.06 has a place, but below 550-600 hp is not it on a 2-rotor. The EFR8374 0.92 is already getting near 600 hp on ethanol (btw the earlier 8374 dyno I posted as comparison was on E98, they are shooting for 40 psi eventually). Sorry if I wasn't clear.



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Originally Posted by wangracing (Post 11904375)

Am running the 8374 with 1.05 hot side fully divided short manifold and twin external gates on my mildly ported 13BREW. Is running E85 fuel. Was chasing area under the curve and response as opposed to peak number as it is a tarmac rally car. Car is running 20psi, is hitting that at approx 3200 rpm and making 442 ATW. Am very happy with the results. Great initial spool up and power, epic midrange and top end and great transient response on and off the throttle. Spool is just always there. The minute you breathe on the throttle its making boost.

I would have considered the IWG for simplicity but they were an unknown quantity as to whether the internal gate could cope with rotary flow when we were at that stage of the build so we erred on the side of caution with the ext gate setup.

http://img.photobucket.com/albums/v94/cdrra/image-1.jpg

http://img.photobucket.com/albums/v9...a/IMG_0664.jpg

Originally Posted by TeamRX8 (Post 4703872)

vs 0.92

20 psi @ 3000

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Originally Posted by TeamRX8 (Post 4704191)

go compare against area under the tq/hp curve that I posted for the 7670 that you don't have to rev to the moon = fail.

Originally Posted by Turblown (Post 11797678)

I am starting to wonder if we will continue to even sell the 7670. The 8374 delivers amazing response with much better midrange and topend compared to the 7670. I do not see a reason to have any better response by moving down to the 7670. Also lower egts and backpressure of bigger turbine section on 8374 is a big plus as mentioned.

Originally Posted by Brettus (Post 4704491)

Went in to discuss layout ... he at least thinks it's possible to fit it all in the way I want it . Still looks very tight and there may need to be some compromises . He seems against the idea of hammering the firewall out of the way so that makes it harder to fit .

Originally Posted by hoss -05 (Post 4704525)

All of the locals have clearanced their firewall when running anything other than the stock greddy turbo. It helps a ton.

Originally Posted by Brettus (Post 4704588)

Nice ... proving once again that booze solves many problems !

Originally Posted by 9krpmrx8 (Post 4704587)

https://cimg4.ibsrv.net/gimg/www.rx8...d1b7abcf03.jpg

Originally Posted by RotaryMachineRx (Post 4704626)

Also I over tightened one of the bolts on my down pipe where it connects resulting in the bolt head shearing off.... probably minor but it is most likely resulting in a small exhaust leak.

Originally Posted by TeamRX8 (Post 4704673)

I have an extra one lying around, lmk

Originally Posted by Brettus (Post 4704687)

Only used studs on mine . Which one is it ? easy to get to or ?

Originally Posted by RotaryMachineRx (Post 4704749)

Sending PM!



Brett I'm not talking about the downpipe to the turbo, cuz yeah those are all studs (and one or two of them are a real PITA); I meant the air pump hose to the downpipe.

The top one is the sheared off one, if I just remove the bottom one and pull the air pump hose off I should be able to get a set of vice grips on it I hope. Then just need a new bolt and the blocking plate.

Originally Posted by Brettus (Post 4704690)

In other news . Saw some progress yesterday . Turbo has ended up lower and it clears the firewall without any pounding.
Wastegate is in position.
Routing of pipes to turbo sorted .
Engine mount sounds like it's going to look like a spaghetti meal gone wrong ..... Fabricator said it was "doing his head in" . But he likes a challenge so I think he is a good man for the job.

Originally Posted by hoss -05 (Post 4704784)

Lower huh? So what are you gonna do with the oil drain. Mine is really at the limit of what I would be comfortable with.

Originally Posted by RotaryMachineRx (Post 4704828)

Very much so, I let the fact that it is twin scroll slip my mind for a moment there! Haha

I have to agree with Logalinipoo, looking pretty low, looks like there isn't much room between the oil drain plug and the manifold in that first pic?

Originally Posted by skc (Post 4704832)

May be worth adding a air duct to keep thing cool. The foot well may get a bit hot.

Originally Posted by logalinipoo (Post 4704823)

getting low

Originally Posted by logalinipoo (Post 4704855)

I mean the piping to the bottom of the car. It looked like that loop might be getting close to the crossmember.

Originally Posted by TeamRX8 (Post 4704851)

Not really, in the first pic the chra is clearly shown to be well above the oil pan

What concerns me is I don't see how they held the elbows out of the exhaust flange so tight to the engine while still allowing the full elbow radius (especially the rear one). It appears like the elbows were short cut to fit that tight, which is not going to flow well at full tilt if they were. Can't tell accurately from the pics though.

Originally Posted by RotaryMachineRx (Post 4704931)

I also meant the header piping.... considering a runner from the Siamese port still needs to fit in there somewhere with an EWG and tie into the downpipe which I am assuming will run even below the header piping shown in the picture already?