Out of curiosity, which cams was he running with the Full? M1's? M2's? If M1's, then I'd expect the top end to fall off some, but if M2's then I'd like to see/hear more about the top end pull on the car when it was equipped with the Full. Please let me know.

 

Ok so I will do my best to answer all the questions, please keep in mind this is in my honest opinion, no expert just enthusiast. I have transfered the two dyno graphs for this car when it laid down its highest # on the full and the inital tune, which ran out of fuel on the BBK-B, (it has since been retuned and to my knowledge running around 26ish psi, to limit stress on motor and in the neighborhood of 417-42x, I do not have or seen the new dyno graph.)





Transient response:The sweet spot seemed to be 3000rpm on the BBK-B. Now this was driving on a closed Mexican two lane road with near or above triple digit speed, so coupled with this turbo's preference to run into the rev limiter I was not paying super close attention to the rpm at the hundredth degree of accuracy. Any lag from there on was indistinguishable. With the BBX I found a high gear below 2500rpms would experience some lag but once you get to 3000rpm's hold on, I found that the spool between the BBX and BBk-B are similar so you can take whatever reference from that.

With regards to slow hairpin, at a 5mph roll 1st gear on an MR 6-speed was annihilated. It literally felt like we went maybe 50ft and 1st gear was gone. You gain speed so fast compared to stock. Chad will be the best judge for auto-x turbo. If you are running small tight courses I can assume the Full with its slight advantage in spool would be a preferred. Will the difference in lag be eclipsed by the added speed the BBK-B offers? I think this come down to your driving style, how much you brake boost, mods etc.

Car has M2's. With regards overall upper rpm pull/feel. All of this discussion is based on 93oct numbers, I have never been in or had experience with E85 so I do not want to speculate. This car put down over 400 on the CBRD mustang on the Full which would be considered rather strong, many people see anywhere from high 380s to low 400's with the Full, so you can assume that those in the 400's are reaching the higher power level for this turbo. Where with the BBK-B we have seen 420's-460's depending on headwork. This turbo has more a lot more left in the tank with built and potentially stroked motor. Feel is equated to maxing out something BBK-Full versus just entering sweetspot BBK-B in terms of power.

The above dyno graphs where done in very different temperatures. When the Full was dyno'd outdoor temps where in the 20-30's, with the BBK-B it was this past summer so pretty darn hot. When you look at the upper region of the rpm's you can see the slope of the Full graph starts to decrease where if you look at the BBK-B(and have to ignore the knock drop) the slope is staying constant and steeper through the curve. The B has much more to give where the Full, given these mods, was getting close to its max. You can feel the difference in driving it, redline simply needs to be extended.

Alright I think that covers everything....

 

what do you have redline set at?

 

7800 or 8K can't quite remember. Tend to shift around 7500.

 

Just for reference, what was the car using for boost control? Looks like he was losing nearly 3 psi from peak to redline with the Full, and less than 2 psi from peak to redline with the BBK-B. I would think that with a EBCS he could dial out that boost taper, and theoretically help keep the power curve going up more. Right?!

 

On the BBK-Full AVC-R, which had problems and ended up being pulled. Stock BOV

On BBK-B, EBCS not sure which brand. Also has APS BOV.

I do not really want to speculate anything and have tried to be objective with the info. I cannot speak to whether or not some of the taper was due to boost control inefficiencies, head flow inefficiencies or simply the tune for safety sake. My very vague memory on this is that the tune tapered. It has been nearly 2 years since the BBK-Full went on said vehicle.

Looking at the dyno sheets in the BBK #'s thread, the cars w/o taper in boost had more headwork. This car is #7 on the list. https://www.evolutionm.net/forums/se...ts-thread.html

My experience in the car is that at/near redline boost is still right around 25+ psi.

The BBK-Full is an awesome turbo and judging by your sig you have one coming. Congrats, it is a wise choice. Is GST doing the install and tune?

 

I completely understand not wanting to speculate, but thanks for all of the feedback, and for sharing your personal experience and perspective. My Full is actually already in the possession of my builder/tuner(KevinD with EvoDynamics). He has been taking care of getting my hotside, EM, and O2 ported and coated prior to the install of all of that along with the S2's. After all of my research, my hope was that the S2's and ECU controlled boost would be enough to keep the Full from falling on it's face above 7,000 rpm. Maybe not. Either way this set-up is going to be a temporary solution until I have the funds to build a 2.1 or 2.2L for a BBK-B upgrade and E-85. Thanks again!

 

I think falling on its face is a little relative. From the Subaru world some models lose half of the peak boost by redline, including mine !!

The BBK-Full is my not means a slouch up top, there are a number of BBk-Full boost charts that plateau and hold, this is 1 sample under X conditions. Chad hated the AVC-R and it was constantly being weird. The ECU boost control used now with the BBK-B is significantly more responsive and smooth.

Sounds like you did all the right research in choosing an awesome set-up. The Full is a blast! Best of luck with the build

 

Thanks! A lot of the stuff I'm using, and about to use soon, is based on Chad's recommendations. We're shooting for peak and hold of 26-27 psi, so we'll see how it turns out. Are you planning to keep your Subie, or are all of these 400+ whp Evo's swaying you over to the Evo side of the fence?

 

Mr. Block... Calling Mr. Block... any updates?

 

got my ported CBRD BBK Full. Car will hit the dyno Wed. 360-370whp (Mustang Dyno) on 91oct here i come.

 

I am going to be perfectly honest here. I have done one autocross on my BBK Full thus far and I would not give up any more spool at the expense of power. I love the turbo but I would be lying if I said that it spools EXACTLY like stock. It is a tiny bit lazier down low. Maybe going from stock cams to GSC S2s has something to do with that. The point is, the BBK-B will be a little bit lazier than the Full. I have not driven a car with the B but based on my own experience with the Full, I would say the B is overkill if autocross if your activity of choice.

 

Completely agree. The Full is definitely the limit on turbo size for auto-x.

 

CBRD always hard at work and it sure paid off!!! Congrats! Great numbers!

 

Tuned a final production BBKB today on a 2.3L, E85

518whp/509wtq

Held 30psi to 7k+

The car made 460 whp with a BBK-Full

I'll scan the sheets and make an actual thread in the next couple days

- Bryan