My First Run Impressions and Testing Results with (knockoff) Billet Power Blocks

[Tatsu333]

Just wanted to share my first run impressions and testing results after installing my knockoff Billet Power Blocks (you can read about my install and knockoff vs. genuine discussion on my build log here). Despite some dissenting opinions across the forums, I decided they were worth a try based on a couple of threads (here and here) speaking really highly of them. There was also an article from Moto IQ that, again, was very enthusiastic about the results. In those threads and that article, they call the BPB's a "no brainer" and "pretty much the best bang for your buck" for an NA car, so I figured, why not?

Since I don't have a dyno in my garage, my comparison testing is done on the road, with as close to the same conditions as possible for each run, and as little time between runs as I can. For comparison, I'm looking at the time deltas between certain RPM ranges (in this case, 600 rpm increments from 3000 - 6600 rpm). All runs are on Shell V-Power Nitro+ 93 octane from the same local gas station.

A few caveats / notes with my results here:

First, I couldn't, for obvious practical reasons, do back-to-back runs before and after the BPB install, so the stock numbers I'm comparing with are from a different day, but same stretch of road, temperatures within 1-2 degrees Celsius of today and similar weather conditions, so they're not going to be WAY off.

Second, after my first run with the BPB's and the stock tune loaded this morning, a speed trap was set up right at my highway on-ramp testing spot...LOL. So, I ended up having to resort to a different, straight and relatively level road afterwards for a couple more runs. I re-did a run with the stock tune, and then switched to my tune with mild cam timing changes to do a back-to-back there, but had to do those on-the-go moving down the same road rather than repeating the exact same stretch since there wasn't any good place to loop back around. I didn't expect to see massive differences between the stock tune and my cam tune anyway, so didn't think it was worth it.

Third, I didn't log anything below 2500 rpm previously, so I have nothing to compare to there, but I will say that from 1500-2500 rpm, while still certainly not "strong" by any means (and not where you'd really want to drive anyway), it does feel like it pulls a bit more smoothly / doesn't struggle as much. Even up some small hills at that low rpm, it just pulled smoothly where before it would really be chugging, so I'd agree that there are gains in the lowest range.

Fourth, the only changes in my tune are some pretty mild cam timing changes. Fueling / AFR targets and ignition timing are all still stock.


Comparison #1 - 100% stock vs. BPB + stock tune (3000 rpm - 6600 rpm tested)

• 3000-3600 rpm = 2.5% faster with BPB's
• 3600-4200 rpm = 1.0 % slower
• 4200-4800 rpm = 2.5% faster
• 4800-5400 rpm = 0.7% slower
• 5400-6000 rpm = 10.5% faster (!!!)
• 6000-6600 rpm = 0.4% faster

So...WOW! Subjectively, it did feel quite strong from just above 5000 rpm to just above 6000 rpm, but WOW. Over 10% faster (1.321 seconds vs. 1.46 seconds stock).

While the other ranges are almost kind of within margin for error from one test to the next (though I do believe anything more than 1.5% could be considered a valid improvement or loss), there's no discounting that magnitude of change. DEFINITE improvement on the road.


Comparison #2 - BPB + stock tune vs. BPB + mild cam tune (3000 - 6600 rpm tested)

• 3000-3600 rpm = 1.9% faster with my tune
• 3600-4200 rpm = 2.5% faster with my tune
• 4200-4800 rpm = 0.1% slower with my tune
• 4800-5400 rpm = 2.4% faster with my tune
• 5400-6000 rpm = 5.8% faster with my tune (!!!)
• 6000-6600 rpm = 1.5% slower (this region is unchanged in my tune)

Again, there were even more gains in that 5400-6000 rpm range with my mild cam tune (about 1 degree more intake advance in that range is all), which suggests there may be more improvement to be found there with a bit more overlap (either more intake advance or exhaust retard). That's a total net improvement vs. stock if you add both comparisons together of about 15%, which is great!

My tune was quicker through 3000-3600 rpm on top of the gains from the BPB's alone, recovered and improved on the slight power loss on the stock vs. BPB run in the 3600-4200 rpm range, and was basically dead even from 4200-4800, so a definite (small) improvement through the torque dip area. I feel like there's a bit more to be gained with some further tweaks to cam timing here before I start playing with fuel and ignition timing.

Likewise, my cam timing changes gained a moderate bump in the 4800-5400 rpm range vs. a slight power loss on the stock vs. BPB run, leading into the bigger gains from 5400-6000 rpm.

While there was a slight loss shown from 6000-6600 rpm, that's a range in which I haven't actually changed anything with my tune, and with it pulling harder in the previous 600 rpm you'd think it would at least break even. Maybe I can chalk that one up to a slight gradient increase on the road I was testing at on the "tuned" run during that range...


SUMMARY

On my otherwise stock car, the BPB's show measurable improvement even without any tuning changes, including a BIG improvement in the upper mid-range. With only mild cam timing changes, further improvements were found across the board.

Next steps for me will be trying out further cam timing changes through the torque dip range to see if we can squeeze out a bit more improvement, and also from 6000 rpm up to see if we can offset a little of the top end drop-off in power that's an expected consequence of lengthening the intake runners with the BPB's.

Once I feel like I've gotten all I can out of the cam timing, I'll start tweaking fueling and ignition timing.

[Lantanafrs2]

Here come the comments from the experts who've never used them

[Tatsu333]

Originally Posted by Lantanafrs2

Here come the comments from the experts who've never used them

Oh yeah, I'm fully expecting that, given the history with the BPB's on this forum...LOL!

[Ohio Enthusiast]

Great experiment!

From my understating the blocks are supposed to pull the power band down. I wonder if a comparison between 6600-7200 would have shown a 10% decrease (basically the 6600-7200 without blocks would be the same as the 6000-6600 with the blocks).

[Ohio Enthusiast]

Great experiment!

From my understating the blocks are supposed to pull the power band down. I wonder if a comparison between 6600-7200 would have shown a 10% decrease (basically the 6600-7200 without blocks would be the same as the 6000-6600 with the blocks).

[Tatsu333]

Originally Posted by Ohio Enthusiast

Great experiment!

From my understating the blocks are supposed to pull the power band down. I wonder if a comparison between 6600-7200 would have shown a 10% decrease (basically the 6600-7200 without blocks would be the same as the 6000-6600 with the blocks).

Quite possibly.

Not sure that it would drop that much, as we're kind of actually talking about what would have been "possible" between 7200-7800 rpm being shifted down to 6600-7200, but I would expect to see a drop since the stock powerband is fading from 6800-7200 rpm anyway (at least on the baseline dyno of my car from a few months ago).

I didn't bother going right to the limiter on any of the runs so far, but will do so when I'm working on tuning the top end of the range to see what (if anything) I can gain back.

[Lantanafrs2]

I use them along with uel header and e85. May miss a little on top but I'm not worried about it.

[Tatsu333]

So I finally got around to getting my car back on the dyno to test out the gains with the Billet Power Blocks installed.

The highlights are:

• Peak vs. peak gains of 3.9 hp and 8.9 lb.ft. of torque on an otherwise stock car, on the stock tune (171.5 hp @ 6550 rpm and 142.4 lb.ft. @ 6,250)
• Gains literally EVERYWHERE up to about 6,800 rpm
• More torque down low, with a 6.5 lb.ft. gain vs. the old torque peak at 3,210 rpm (140 lb.ft. @ 3,000 rpm vs. 133.5 lb.ft. @ 3,210 rpm)
• Torque dip substantially narrowed (though still present), with a big surge in torque around 4,200 rpm (about a 14 lb.ft. gain here)
• Gains of 6-10 lb.ft. from 5,000 - 6,250 rpm

You can read all the details and see the dyno sheet (same car, same fuel, same dyno and operator, but about 7 months apart between my baseline stock pull and today's runs) on my post in my Member Journal here.

In short, I would HIGHLY recommend the Billet Power Blocks to anyone with a 1st gen BRZ/FRS/86 who is staying NA, and especially if you're going to stay otherwise stock.

[Lantanafrs2]

I wonder if these will work on a '22?

[Tatsu333]

Originally Posted by Lantanafrs2

I wonder if these will work on a '22?

With the added displacement already adding a bunch of torque, I don't know that the difference would be as pronounced, and there just isn't as much need for the downward-shifting of the power band anyway.

That said, with the ECU still being locked on the 2nd gen, it could be worth a shot to see if there are any gains to be had (presuming they would fit - I have no idea if the runner shape, etc. is compatible between the 1st gen and 2nd gen).

They're easy enough to install, and the knockoff BPB's are cheap enough that it wouldn't be a huge expense to experiment for someone with a 2nd gen...