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Discussion Starter #1
Im getting ready to do either a 2.2 or 2.35 upper and fic 1000cc injectors. If I do the 2.2 and port the blower and snout would that put me to high of boost?

Im currently running
2.55 upper
Airaid CAI
Stainlessworks 2" headers
Stainlessworks 3" catless full system

Im seeing just over 12* boost . And will probly be doing a cam later this year. Any thoughts
 

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I'm not the end all expert on this but, I believe porting the super charger alone is going to give you roughly 2lbs, anyone feel free to correct me on that. But going to a 2.2 will be at risk for belt slip and probably run into some sort of clearance issue without adjusting your idler pulleys too. I think your best option is to do a bigger lower pulley while your doing your cam, you can maintain your current level with cam, or up your boost if need be while retaining a solid belt wrap. Make sure to get some cooling mods on there or you wont see max potential.
 

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I would wait to repulley from the bottom when you do the cam install. I have a 2.38 and see 14-14.5 psi of boost. Any smaller than that and I'd be moving nothing hot air through the engine. Also a 2.38 required a little bit of grinding of the snout which for the DIY'er can be easily done at home. Anything smaller than a 2.38 and you'll need a machine shop to mill the snout. Save your money for the cost of pulley, belt and milling and keep your existing pulley.

Not sure what a ported blower will result in, so i'll leave that for someone else to answer.
 

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What supporting mods do you have with the 2.38 upper
It's in my sig, but here it is in case you can't see it:

Stage 1 Mods:
Airaid CAI w\Sideswipe
Kook 2" headers, Kooks 3" off road x-pipe, Corsa Sport mufflers
C&R HX, BMR Reservoir, ZL1 Lid, Varimax pump, 160 T-stat
Pat G. Engine and Transmission Tune: 493 HP & TQ w/93 Octane on Mustang MD250 Dyno

Stage 2 Mods:
Fore Fuel Pump setup w/ID 1300 Injectors and Flex Fuel Sensor
2.38 Pulley w/Green belt & Green Air Filter
NGK TR7IX plugs and Mighty Mouse catch can
Pat G. Tune: 554 HP/570 TQ on 93 Octane - 616 HP/633 TQ w/E85 on Mustang MD250 Dyno
 

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Discussion Starter #7
Im doing atleast 2.35 upper just trying to see if the blower port would be worth it for me . Or i could just spend that money on the zl1 lid. Or cam swap now. Dammit i cant decide.
 

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I'd guess around 1.5psi max, as you'll be head-limited already having headers. I'd estimate slightly more than 1psi for the ported blower - assuming reputable port work, and MAYBE a half-pound for the extra pulley.
 

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I'd guess around 1.5psi max, as you'll be head-limited already having headers. I'd estimate slightly more than 1psi for the ported blower - assuming reputable port work, and MAYBE a half-pound for the extra pulley.
Gents,
Assuming you don't repulley the blower, wouldn't a ported blower reduce the PSI? You're not spinning it any fast and by porting it you increased it's volume. I know in the Ford pony world guys that would port their blowers would either keep the same boost or in some cases drop 1-2 PSI's.
 

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Gents,
Assuming you don't repulley the blower, wouldn't a ported blower reduce the PSI? You're not spinning it any fast and by porting it you increased it's volume. I know in the Ford pony world guys that would port their blowers would either keep the same boost or in some cases drop 1-2 PSI's.
Negative.

First off, and it’s just wording, but you aren’t increasing the volume (displacement) of the blower, but of the intake.

Porting the blower before the rotors allows more air molecules (mass) into the blower, which then passes into the lid.

If everywhere after the rotors remains the same, you are pushing more air into the same space, so there’s more compression of the air, which shows up as an increase in psi and temps.

Control the temps and you make more power.


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Discussion Starter #14
I have not had one of these blowers apart yet so i may sound stupid here but i was thinking snout porting = more boost but i thought they aslo ported the plenum (after the blower) would result in less resistance less boost thats why i asked the op
 

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I have not had one of these blowers apart yet so i may sound stupid here but i was thinking snout porting = more boost but i thought they aslo ported the plenum (after the blower) would result in less resistance less boost thats why i asked the op
As karch said, efficient porting pre-rotor increases air charge and thus increases boost if no other changes. Post-rotor porting does not increase the air charge but could increase flow efficiency, and lower boost.

With the TVS1900 and typical LS heads there seems to be no benefit to post-rotor porting (and less than a 5hp gain when I had my mismatched head ports fixed). With this blower, the "plenum" is still pre-rotor.

The money shot is all pre-rotor intake restriction, assuming a competent porter.

In other platforms that have different case designs, intake runner arrangements and / or better flowing heads - well, it may be different!

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