LSx 78mm or 90mm
#1
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Hey guys
I have been looking into a new intake. I was wondering how much hp you would need to see a difference between the 2 intake sizes? I know the only difference between the sizes is the tb opening . The rest of the intake is the same inside. I am wondering How much hp can be made with a 78mm opening before it becomes a restriciton? I mean if I still have a 75 mm opening on my lid and 75 mm mass air what could the 90mm really do for me?
thanks
Jeremy
I have been looking into a new intake. I was wondering how much hp you would need to see a difference between the 2 intake sizes? I know the only difference between the sizes is the tb opening . The rest of the intake is the same inside. I am wondering How much hp can be made with a 78mm opening before it becomes a restriciton? I mean if I still have a 75 mm opening on my lid and 75 mm mass air what could the 90mm really do for me?
thanks
Jeremy
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generally you would use the 90mm fast intake for larger cubed motors. thats where you'll really run into the restrictions on the intake, not necessarily hp. although, the stock maf's hp rating is said to be somewhere around 650 hp, and then you need to go to a larger size. at that point the 85mm z06 is the way to go i do beleive. some people think that when you put the 90mm intake on stock cube motors, its overkill. however i've seen that you still see improvements over the ls6 intakes, and i think that while its not worth the money to upgrade from the 78mm fast to the 90mm fast, its a better idea to go for the 90mm fast the first time around.
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Originally Posted by smokin' joe 00 ss
I went with the 90mm and I glad I did, 27 rwhp gain over the LS6.
Thats a pretty bad *** gain, who knows what i gained, i installed a trex, lsx 90mm, and a under drive pully all at the same time. I hope to get it dynoed soon
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I have a quick Q for ya, What if you were to install the 90mm on just a stock set up on an LS1.....Would there still be gain or would it flow to much air and not run properly?
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Originally Posted by 00TAProject
I have a quick Q for ya, What if you were to install the 90mm on just a stock set up on an LS1.....Would there still be gain or would it flow to much air and not run properly?
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I got the LSX 90 setup, its badass, if you go with the LS2, you will end up paying about the same money because, 1. you will need new injectors, or adapters, 2. new fuel rails, and the MAP sensor mounts in the front instead of the rear. Just seems like to much of a hassle just for a intake IMO.