Plenum hype finally died down?

VatStang said:

I've had my C&L plenum for months now. I love it. Its not a CRAZY bolt on, but when used with a MAF, TB, it is supposed to give you about 7rwhp. The accufab posted the most gain with about 8.5 rwhp. The Dragon plenum was supposed to make the least.

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wrong, trickflow made the least hp and tq peak... also don't forget that peak numbers aren't everything.. look at hp and torque between C&L vs. Dragon throughout the rpm band. This is why only looking at peak numbers can be deceiving.
C&L 75mm t/b

Dragon 75mm t/b

(borrowed from modular depot thanks to Matt for the tests)
And that makes me still content with my dragon
-wade

Here's some info that's not very scientific about the plenum/TB mod, and I'll let everyone form their own opinion. And I'll share mine . . . I like this mod, and I got this combo for a really good price (can't remember exactly, but it was like $370?). The jury's still out somewhat for me on the mod, but so far, I'm liking this mod. However, I wouldn't pick it over 4.10s and sticky tires!

Of the first 24 passes I made at the same particular track in all sorts of track conditions and air temps and various levels of modifications (but all pre-plenum/TB), I ran a best ET of 14.1 (only once) and a best mph of 99.98 (ran high 99's most of the time.) I generally ran 14.2-14.3s at this particular track, even with 2.13 60's.

In the last 3 runs I just made at this same track (first 1/4mi of the year for me), my best ET was 13.824 and best mph was 101.4. The other ETs were 13.9X, 14.0X. The other MPH were 100.0 and 99.58.

Here's the wildcard: I also ran Nitto DRs and used a shift light for the first time.

So the million dollar question is, "Does better traction (DRs) help with mph?" I'd like to know. I've had a few veteran drag racers at the track tell me better traction often improves ET but can lower mph. If that is indeed the case, then I would start to believe that tb/plenum combo was worth something measurable at the track.

I guess I look at it this way - if I continue to improve my times and generally run over 100 mph the rest of the year, then I'd have to think the plenum/TB was worth something measureable. I still swear on my mustang that I actually "felt" this mod - the dynoes performed would also make me believe this, as I recall there was one spot on the curve where the gains were approaching 10 rwhp and similar tq over the stock TB/plenum. For reference, I don't think my "butt" dyno is being overly optimistic, especially since I readily admit I didn't feel a darn thing with pullies (although my mph has been about .5 mph better ever since the pullies too!) But I guess that's another debate!

Anyone know what going from stock rims/tires to a pair of 17 x 9s and a set of 275 Nitto DRs will generally do to MPH?

As far as my recent best ETs posted here . . . there's much more to be had. My 60' times generally sucked despite the DRs. However, I hooked WAY better on the 1-2, and 2-3, which definitely helped ET but I have no idea what sort of effect this increased traction would have on mph.

todd4566 said:

The Accufab is supposed to come w/ shorter bolts for mounting the IAC and the TPS sensor (even if you didn't order a t-body). If you didn't get them, then either call Accufab, or head to the hardware store.

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That's exactly what my combo came with - the shorter bolts.

I've had my Accufab 75 mm tb and plenum for about three weeks. No problem with installation and it runs great. The car seems more responsive during acceleration. It is not, however, an inexpensive mod. Around $420 for about 6.31 rwhp. Other mods probably provide more bang for the buck, e.g., ud pulleys, x-pipe, gears.

The Accfab plenum and 70mm TB go on Thursday. The weather has not really been nice enough here on Cape Cod to take the Stang out much.