BT 2 x 4 intake better than MR?

[67xr7cat]

Are some new BT MR 2x4 intakes on ebay. The one seller claims that the BT intake has over time been improved over the original ford version and worth 50 to 70hp. Am assuming over the original, but maybe means over a 2bbl intake
Just was wondering if any truth to the newer intakes being better.

[67428GT500]

It's BS. The quality of BT products can't be argued, but C7ZX/MR dual plane Vs. BT there is no way there is a 50-70 HP in improvement.
                                                                                                                          -Keith

[plovett]

Per Jay's book, I think the Factory 2x4 MR and the BT version were almost identical in terms of power production.

paulie

[chilly460]

I need to go review in detail, but I recall the BT being 15hp or so better at higher rpm on a 550-600hp deal, below that they were even.  So, no, it won't bring 50-70hp at all. 

I picked up a BT 2x4 this summer and was deciding between the two, the BT is a beautiful piece.  It was just a matter of availability and price for me, the small performance difference didn't factor. 

[67428GT500]

I saw the listing referenced. The claim was 76 HP. California. Must be smoking something.

[plovett]

I need to go review in detail, but I recall the BT being 15hp or so better at higher rpm on a 550-600hp deal, below that they were even.  So, no, it won't bring 50-70hp at all. 

I picked up a BT 2x4 this summer and was deciding between the two, the BT is a beautiful piece.  It was just a matter of availability and price for me, the small performance difference didn't factor.

If the BT was better it was probably because it was port matched while the factory intake was not.  Check.

[jayb]

The strongest engine I tested those two together on was my 427 dyno mule.  Peak torque for the Ford and Blue Thunder manifolds was very close, 527.8 lb-ft for the Blue Thunder and 526.6 lb-ft for the Ford manifold.  However, the BT manifold was a little better on HP, 596.9 vs. 577.8.

On my 390 stroker the differences were much less pronounced, 512.1/517.7 (torque/HP) for the Blue Thunder, and 516.8/517.7 for the Ford.  The Ford manifold was actually a little better on torque than the Blue Thunder manifold, on that engine, which makes sense if the internal passages of the Blue Thunder manifold were bigger.  And they were exactly the same on horsepower, which is rather remarkable...

Neither intake was port matched for these tests, but the Blue Thunder intake did have larger ports.  Port sizes were 1.22" X 1.92" for the Ford, and 1.35" X 2.09" for the Blue Thunder.  That was at least a part of why the BT intake was stronger on the higher power engine, and could be the whole reason.

[Drew Pojedinec]

I dunno about anyone else, but I have no issues whatsoever carving heavily on a BT intake, whereas I wouldn't think about even port matching an original.
That reason alone makes me think, if peak HP was the goal, I'd be buying a BT.

[Posi67]

I have an older BT 2x4 on my 390 and it runs pretty good with zero work done on it. The newer versions may be revised as they now have the C7ZX on a runner whereas mine doesn't. Either one likely makes a 70 HP improvement over a 2 bbl as the OP surmised but certainly no where near that compared to a Stock C7ZX.

I used to have a C7ZX on my 427 and sold it to buy a Dove T-wedge otherwise I'd try it on my 390 for comparison. I'm interested to see how much the TFS T-Wedge costs because that may be worth some power. I think the Dove and BBM T-wedges are a bit big for that motor and both currently have other jobs anyway.     

[67428GT500]

The C7ZX is to cater to the Shelby crowd. There were no changes in the intake itself, other than about 100.00 Ford gets for royalties.

                                                                                                 -Keith