smallest turbo on a 408

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Sep 2, 2008 | 05:15 PM

T2SLS1

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From: Arlington,tx

smallest turbo on a 408

I'm having a 408 built. It was origanaly built for nos, but i came cross a deal on 2 turbonetics t70 turbos i could not pass up on.. but i only want to run one.. Whats the smallest turbo i can use on my 408 then later go up to a 80-100mm turbo after i set the car up,fuel,suspension etc. my goals for now are med to low 10's for now.

Sep 2, 2008 | 05:28 PM

ninetres

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Way to small to feed a 408. Use both.

Sep 2, 2008 | 05:40 PM

CamaroSS19

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Thats what I was going to say IMO a 70 is too small for a 346

Sep 2, 2008 | 05:56 PM

Pat-Man

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I would say a 76 is the smallest you can run on a 408. Any smaller and its way too much of a restriction on the motor.

Sep 2, 2008 | 06:50 PM

topend

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Quote:

Originally Posted by T2SLS1

I say run the single t-70. good for about 800 hp.....

Sep 2, 2008 | 06:50 PM

T2SLS1

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part 2

Now that this his been solved twin t70 or sell for a larger turbo! i purchased a set of tfs 240cc heads are these over killed for a turbo car, should i just use l92 with carb intake and out money back into motor are turbo build?

Sep 2, 2008 | 06:58 PM

rubbersdown

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run the twin t-70's that would be a pretty nice setup.

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Sep 2, 2008 | 10:27 PM

MonochromeSS

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70 is too small for a single on a 408, 76 is pretty much the limit for those cubes.

Sep 3, 2008 | 09:00 AM

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DrTurbo

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70mm would choke a 408 like a rock. Also would probably have a headgasket failure from the excessive backpressure.

Sep 3, 2008 | 09:32 AM

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hellbents10

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Agreed, go with a smallish t6 unit if at all possible to get you buy. If cost is an issue you can get a s400 for $600ish.

Sep 3, 2008 | 10:13 AM

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Mike 01WS6

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I'd go with an 88 bare minimum on a 408. You're just asking for problems if you go any smaller.

Sep 3, 2008 | 11:22 AM

#13

Shawn @ VA Speed

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you def need to go with and 88mm or bigger with a t6 flange,anything smaller is asking for trouble

Sep 3, 2008 | 12:26 PM

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TURBO383WS6

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these guys know what they're talking about. i had a T76GTS on 383ci and it was way too small. an 88 should spool quite nicely on 408ci. i'm in the process of swapping to a GT4788 right now and i'll get back to you on the difference.

Sep 3, 2008 | 12:29 PM

#15

DrTurbo

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Quote:

Originally Posted by hellbents10

Agreed, go with a smallish t6 unit if at all possible to get you buy. If cost is an issue you can get a s400 for $600ish.

Correct....also Garrett now has a line of Budget units. From 76 to 88mm

. Under 1200 bucks.....GT47 comp, 94mm Turbine...T6 frame...etc..etc.

Sep 3, 2008 | 12:45 PM

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Pat-Man

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what kind of problems would you start seeing? You guys are getting me worried now with my 408 and T76....

Sep 3, 2008 | 01:04 PM

#17

DrTurbo

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Quote:

Originally Posted by Pat-Man

what kind of problems would you start seeing? You guys are getting me worried now with my 408 and T76....

Backpressure through the roof and head lifting. All a part of running a small charger on a big engine. If you are shooting for big #'s, you will have nothing but headaches.

Sep 3, 2008 | 01:10 PM

#18

Pat-Man

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From: Georgetown, Texas

IC...I'm only running 3 - 4 lbs now (trying to save tranny). Plan on running 15 lbs for maybe 750 to the wheels. Eventually will run something bigger (88) as money allows me.

Thanks.

Sep 3, 2008 | 05:14 PM

#19

T2SLS1

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From: Arlington,tx

how much more extra to run twin t70, a ball park i know pipeing but what about waste gate,blow off etc? and any word on the tfs240 heads for my turbo build is it over kill and should I go l92 with carb intake and put extra cash into my turbo build?