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So I’ve got one of these big dogs porting intakes here…

15517 Views 208 Replies 38 Participants Last post by  96pushrod
A kind gentlemen - who is not big dogs, or affiliated with them sent me a big dogs cobra intake that has been ported. I’ll be replacing the box r intake on the car temporarily to see the difference.

I won’t get into the pissing contest, really here as a third party to make a comparison. Here are some pics of it compared to a factory explorer intake. All measurements are in mm.

This will be a strict a to b comparison deal. I’ll look at fuel flow and dragy times to see which one works the best. Engine is a woody built 347 with a f1r blower. Any ideas on which will come out on top?

If anyone wants any other pics or measurements, please Let me know and I’ll oblige if I can.

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1 - 12 of 209 Posts
I think it will be a bit smaller judging by the 1262r on there now.

I believe it’s just welded on a couple runners to allow for more room to port.
Post up a picture of the welds.
I can say without hesitation that is a butcher job. You would have to pay me to use it.
If you are going to weld on that intake, it needs to be done right. What they did is a waste of time. To do it right you need to take the bends out of the lower runners. What they did is not even half-*.
Plus the cross section area at the head is larger than that at the upper and lower junction, and of that on the entire upper runners. Did they port the upper runners all the way to the plenum? I dont see a weld scar where they cut it open to access that area.
The problem with those intakes is that the runners dont support anything more than a 1250 sized port, even if they are ported. But a blower can make up for alot of compromises.
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As I said previously, "testing" with a blower will prove nothing.
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Of course there is a difference, but it's extremely hard to accurately compare the differences when using boost. A 40cfm difference in heads should make a huge difference in a NA engine, but with 10-15psi boost, the change is likely to be minor. The intake is critical for a NA engine, but comparing a 5500rpm intake to a 7000rpm intake, with boost in the same rpm range, shouldn't be earth shattering.
Plus the prevailing sentiment at the Corral is to use peak numbers, and not area under the curve when looking at whether a part is an improvement.
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How do you figure? If the blower makes power at 11psi, and the intake change increases to something like 13, does that not prove a restriction?
It might, but what does that prove? Perhaps you get more useable power with the "restrictive" intake.
Nothing? We waste are money running the box r or similar with a supercharger?
I think you dont understand my point.

And yes, it very well might be a waste of money buying a Box R on some combinations. That is basic.
I find this one very interesting I have had a few people tell me it's a waist of my time to even test the TFR long runner that I have. They say it sucks. Crazy thing is it has the same lower as the TFR box. This is a prime example of why I like the GT40 intake many many times with a little work they out perform the aftermarket intakes. All but the box that is.
View attachment 1094663
I dont understand your point. Results depend on the goal and combination. Are AFR 220 heads not worth it because they didnt produce more power on a near stock 302? Is the GT 40 intake worse than a Box R because it underperformed on a 7500 RPM 427 windsor?
Complaining like you do above is nonsensical without proper context. No mention of combination or parts used (like heads), and no area under the curve, just peaks. Worthless, really.

Plus, the poster mentioned "track" testing, read carefully. No dyno mentioned. So how did he get max hp and tq numbers????
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wrong reference by me, was not relevant
I know, edited out. Sorry.
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It makes more boost because its restricted.
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