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Topic: What size TB should I go with? (Read 1203 times) previous topic - next topic

What size TB should I go with?

As some of you may have read,  I'm installing the Trick Flow top end kit on the 5.0.  I got the street heat intake rated for 0-5500 RPM's as an optimum runnning range.  I'm going 24#'s on the injectors and was just trying to get a feel of what size TB I should go with.  I'm 90% set on a 70mm.  Just wanted some opinions on it.....

[LIST=1]
  • 65 MM
  • 70 MM
  • 75 MM
  • THE TORPEDOS!    90MM!!!!!!!!!!!!!!!!!


And I made the list because I ca't figure out how to do a poll, sorry.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

What size TB should I go with?

Reply #1
What are the specs on the cam and the heads?  What will you be running as far as exhaust(headers: shorty/full length, cats/no cats, tailpipes or dumps).  I would actually recommend against the Street Heat intake, it falls off much earlier than other intakes and makes less below the curve than others as well.  You would be better off upgrading to the Track Heat intake or even going with something like the Holley Systemax or GT-40.  I would go with the 70mm TB for that application.  Also, if it's an automatic, make sure you go with at least a 2200-2800 stall convertor and some decent gears.
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

What size TB should I go with?

Reply #2
70mm is about the right size size.as far as the intake is concerned,i would say it's according to the rest of your setup.are you running stock rod bolts?if so,5500 is about all you would want to turn it if you are looking for longevity.what cam are you running?don't want much duration if you aren't turning it past 5500.good luck with your project Paul.

What size TB should I go with?

Reply #3
i would go with the 75mm it is not like a carb  one to big  will just help throttle responce as the mass air meter  measures airflow to feed fuel to it.

if not i would go with the 70mm
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Owner of Joe Dirt Fabrication

What size TB should I go with?

Reply #4
It's the TFS stage 1 Cam
http://store.summitracing.com/default.asp?target=partdetail.asp&part=TFS%2D51402000&N=400098+4294887637+4294908331+4294840126&autoview=sku

This is all the stuff I'm putting on.  The motor has forged flat-top pistons which will remain in place.

http://store.summitracing.com/default.asp?target=partdetail.asp&part=TFS%2DK514%2D350%2D370&N=400098+1011&autoview=sku

I'm going with 24# injectors and have all the other associted parts to finally switch to Mass Air.  A new torque convertor is in the works as well, but I'll hold off a couple of months on that.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

What size TB should I go with?

Reply #5
A 75mm will cause a slight loss of low end torque and it might be a little too agressive for the stage 1 cam.  A 65mm is okay but will choke it off a little above 4500rpm, a 70mm is probably the perfect balance for your combo and will even support some further upgrades.
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

 

What size TB should I go with?

Reply #6
I run a 65 with the Stage-1 TF cam and heads, but my buddy runs a 70mm on a similar combo with a Stage-2 cam... He's run 7.7s so it works for him....