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Discussion Starter #1
Alright, I've seen comparisons between the Performer and Stealth, and most seem to put the Stealth above the Performer in both HP and TQ. But, in those comparisons they were always running a bigger camshaft than me, and they were developing peak TQ in the 3000-3500rpm range.

I'm running a Crane 260/272 .487/.518 hydraulic camshaft, Thorley Tri-Y headers, 2.5" dual exhaust, Edelbrock 750, 8:1 pistons (ugh), and right now I have the Performer 460 intake. Soon I'm going to swap in a set of D3 heads I'm porting out, and I figured that would be a good time to swap intakes also and put on a Stealth.

What I'm looking for is maximum torque in the 2000-2500rpm range, because that's my highway cruising RPM with the overdrive and I like being able to pull the hills without downshifting. So do you guys think the Stealth would help, hinder, or have no effect at that RPM compared to the Performer? I'm relatively sure the Stealth will make more HP than the Performer, I just don't know if it's larger volume runners would hinder torque at that low of RPM.

Quite a while back I put a 1/2" fiber carb spacer in to keep the Edelbrock carb from hard starting when the engine got hot, and I remeber it seemed to take quite a bit less throttle to pull a steep grade on my commute.

Given this info, it seems as though it wants a larger intake volume to make more torque. But this was a while ago, seat of the pants feel, and not simple back-to-back testing (because I wasn't expecting a power gain to begin with). If I put a 1" carb spacer on and it pulls the grade even better, would that mean the Stealth would most likely be better?

Sorry for the long post, and thanks for any input.
 

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The Performer sometimes gets a bad rap but there's no good reason for it. A few years ago Super Ford did a intake dyno thrash on a 460. The Performer made more torque between 2000 and 4500 RPM than all the other intakes, including the Stealth. The Stealth is a good intake but it's designed for more RPM so it will give up intake velocity and low RPM torque as a result. For what you're doing the Performer is exactly the intake you need. Blocking off the heat crossover while you've got it off will enable you to run a couple more degrees of initial advance which will increase low end torque a little bit. That's about the only improvement you can make.
 

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Discussion Starter #3
That's really interesting, I always thought the Performer was just a step up from the stock manifold, but not much good for making horsepower because of the small low-profile design. Has anyone seen any other comparisons between these manifolds?

I'd thought about shaving the heads down to get more compression out of them, because that would help out torque quite a bit. But I'd have to shave at least .050" just to loose 10ccs, which would only boost me from 8:1 to 8.5:1. The heads have already had .010 removed, and I CC'd them out to exactly 95cc, so they must've started out around 97cc(!). So overall I think shaving the heads for extra compression isn't really worthwhile.

Thanks for the replies. Do either of you know where I could view this superford article on the web? Or maybe if it's in a magazine only you could do me a HUGE favor and scan it for me?
 

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What's really strange is that the stock Ford intake, with the exception of being a Lard A- is as good as most aftermarket intakes below 2500 RPM.
 

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Discussion Starter #5
Another question along the lines of the head milling: How much can you safely mill off the heads before you start running into problems like intake fit or head cracking?
 
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