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Discussion Starter · #1 ·
Looking at upgrading to a 90mm looking for opinions on what improvements it provided. Will it increase MPG?
 

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I think to get the full benefit of the extra flow provided by a 90mm throttle body, the heads, cam, and exhaust need to be upgraded. Possibly an 85mm would be a better choice if you don't plan on extensive internal engine mods. And I wouldn't expect an increase in mpg.
 

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David
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Like Dave said if you don't have heads cam ect the 90mm tb will hurt perf and probably throw a Cel. Moes has a bored 87mm tb that has gotten rave reviews. Works pretty good with minor mods(Cai exhaust). He also has the 85mm. Fastman has a pretty good bored 85mm tb too.
 

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Thanks Dave and David,
I'll look at the 80 or 85mm I've been also looking at the Volant CAI. I would be doing both mod's at the same time to get the most out them follows by a new CAT back. My goal is to increase my mileage while towing a 31' 5th wheel 6-8 mpgs hits the wallet hard.

Dan
 

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Greg
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Not to discourage, but I installed a FastMan 85mm years ago and didn't notice a difference. I think each mod of this nature simply adds to the overall package making everything better in the end. CAI, TB85, headers, cam, heads, free flowing exhaust. It all helps bit by bit. IMO, it's simple, the more you stand on the throttle the lower your mileage will be. Gears will make the biggest difference and with the wieght yu are towing 4:56 would be my choice. Good luck.
 

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David
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I noticed better throttle responce more than anything. Get yourself a tuner if you don't already have one. You will def notice the performance increase from it. And whilee replacing the exhaust get a magnaflow y pipe. Double 2.5" in 3" out. The factory y is very restrictive. The more air you get in the more you have to get out. Becareful it very addicting.
 

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Greg
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For information about the modified OEM TB's look here.
http://www.thefastman.com/throttlebodiesHemi.php

Duane is the go to guy on the forum for purchases.

Also, I see on other forum who are doing hemi swaps that when they go to a cable drive TB often the choice is the LS 90mm for the modified engines. These come with IAC and TPS and can be mounted with an adaptor plate to the dodge intake manifolds. They can also be bought with a step motor controller. This leads me to believe that the GM electronics are compatable with Dodge. Can that be right? Many of these guys are using re-flashed OEM PCM's. A little off topic but I thought was interesting if we could use a LS TB on our trucks.

http://www.jegs.com/i/Edelbroc...rentProductId=963651

http://www.compperformancegrou...12001&Category_Code=
 

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Mopower or no Power!!
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Welcome Seabee82. Unless you have a lot of work done on your truck, you don't need the 90mm. 85mm will work fine. As for MPG, you might gain a mile or two. You will gain more out of an intake system than a throttle body. And even though a lot of people on here don't believe in them, throttle body spacers, especially Power-aid's version, do actually give you more torque and mpg. We gained 2hp, 5ftlbs, and 2 mpg installing one on our 2006 Dodge Charger RT..dyno proven...Now it may just have been a fluke on the dyno, but it isn't in the mileage...getting 26-27mpg out of a Charger RT with the mods it has I think is pretty good...
 

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Thanks for all the comments once I figure out how to post pic's I will. I have a 2011 2500 Laramie Crewcab LB 4x4. Dollars are limiting how many mods I can do at a time plus momma say's I can only spend some much at a time. I'm looking for a dyno in the Olympia area so I can see the affects of the mods as I do them.
 

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how to post pic's
Upload your pics to a hosting site like Photobucket and use the IMG code format
 

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Greg
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Originally posted by TooCool:
Save the money on the ported TB and do it yourself. Break out the dremel tool and have a little fun.
I like DIY projects, but I don't know if I could duplicate what FastMan is doing.

 

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Oh i'm not comparing my dremeling to his with the proper machinery. But that one is only opened to the throttle blade like mine. For what you get out of a ported TB, i fiqured i use the money for other mod's and do it my self. Think i got the result's i was after being my wot 12.5 afr went to 13.2 afterward. I also opened up the back side to match the intake and polished it while i was at it. It wasn't hard to do and had fun doing it.
 

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Greg
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Originally posted by TooCool:
Oh i'm not comparing my dremeling to his with the proper machinery. But that one is only opened to the throttle blade like mine. For what you get out of a ported TB, i fiqured i use the money for other mod's and do it my self. Think i got the result's i was after being my wot 12.5 afr went to 13.2 afterward. I also opened up the back side to match the intake and polished it while i was at it. It wasn't hard to do and had fun doing it.
TooCool, sounds like you got excellent results. I didn't have a A/F gauge at the time and unfortunately the new TB85 didn't really feel any different from stock. I have the old TB taken apart from experimenting with it and will have to put it back together and test it. Thanks,
 

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Yesterday I installed a TB from Fastman 87mm and a CIA I can tell the difference already.:dance: My average MPG was 13.9 and I will see what these mods produce for MPG. :professor: My next mod will be the exhaust.:brows:
 
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