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Sun May 06, 2018 7:41 am

Like the ancient Egyptians, CB has had a HUGE tech advancement in just a short time. Probably all those PRI events that Pat has been going to. Here's their latest dyno result:

*edited engine size
2387cc
46x38 New Ultra Wedgeports
10.5:1 SCR
.282°@.050" cam, .630" lift
1 7/8" header
48 IDAs w/44 vents
265.9HP @7,000 rpm, and still pulling
No typos
WTF?

Sun May 06, 2018 8:27 am

head/induction side design goes a LONG way.

Im guessing those intake manifolds probably had hours and hours into them as well, but ultimately CB has really put a lot of effort into their head design and I think its going to show in the next couple years.

we've already seen how impressive the new panchito is, but the all new 044 casting is relatively new as well as their new port designs (all less volume but higher flow numbers...more power)

I'd love to see some more specs of this engine, some of the smaller details.

Sun May 06, 2018 9:36 am

ditto. as well as ring's and other things. and look at the low cr it has.....if you stay is the stone ages with the dynosours with your head in the sand nothing changes but the stories and excuse's. keep up the great work and keep brining more new better parts and peace's than any body else selling "almost there parts" could of dream of making in their nightmares.

Sun May 06, 2018 9:39 am

Very impressive! I'm actually in line right now with Pat to build a 2332 (street) for me.

Olli

Sun May 06, 2018 9:59 am

Wow, and they're not in Orange County where there's a OC correction factor.

Sun May 06, 2018 11:30 am

I love CB and their products and great technical support, but those numbers don't add up. 142ci with 265.9hp@7000rpm is a brake mean effective pressure of 14.6. NHRA pro stock engines are in the ball park of 14.75-15 and they have more research and development than ANY VW will ever, not to mention the compression, roller cam profiles, etc.

I have a sheet of about 50 dyno combos, nothing has a bmep above 13.67.

This doesn't have to do with flow, heads, intakes, carbs, it has to do with efficiency. Combustion efficiency, compression ratio, cam will have an effect.

Sun May 06, 2018 11:39 am

HotStreetVw wrote: I love CB and their products and great technical support, but those numbers don't add up. 142ci with 265.9hp@7000rpm is a brake mean effective pressure of 14.6. NHRA pro stock engines are in the ball park of 14.75-15 and they have more research and development than ANY VW will ever, not to mention the compression, roller cam profiles, etc.

I have a sheet of about 50 dyno combos, nothing has a bmep above 13.67.

This doesn't have to do with flow, heads, intakes, carbs, it has to do with efficiency. Combustion efficiency, compression ratio, cam will have an effect.

That's 114 HP/liter. V8s with 2-valves per cylinder only consider these levels a "hot street" engine. 124HP/liter is the highest numbers I've still seen, and they belong to JPM.

Sun May 06, 2018 11:43 am

To put things into perspective.

The CB engine from this engine builder showdown.

Made 224hp @ 6500rpm, with a BMEP pressure of 13.25

Lets assume the BMEP was the same with this new test. IT would need a 91% port ratio to flow enough air for 265hp, and it would make peak power at 7800rpms. That's a LONG way from 7000 rpms.

This stuff isn't voodoo, its science.

Sun May 06, 2018 11:50 am

bugguy1967 wrote:
That's 114 HP/liter. V8s with 2-valves per cylinder only consider these levels a "hot street" engine. 124HP/liter is the highest numbers I've still seen, and they belong to JPM.

JPM made 133hp/l with the 1915. 253hp @ 9000rpms. BMEP of 13.0

What American muscle makes 114hp/l? and what kind of rpms?

Sun May 06, 2018 11:52 am

Another thing to put in perspective. The Porsche 4 liter in the GT3 makes 500hp @ 8250rpm. BMEP 13.5 (12.8:1 variable compression) with one of the MOST advanced engines in the world. But the CB engine was BMEP 14.6...

Sun May 06, 2018 12:14 pm

Maybe Farmersville is close enough to OC.

This "techie" stuff is kewl.

Sun May 06, 2018 12:15 pm

I see what you're saying about brake mep. I just read your o.p. I've heard their numbers were questionable. Maybe I'll ask.

Sun May 06, 2018 12:42 pm

Just read a new post. Pat says the engine had no alternator.

Sun May 06, 2018 12:43 pm

Absolutely they can be over 15bar, at torque peak. This engine with 231.7 ft-lbs it had 16.7bar! Torque peak is peak efficiency, it declines from there.

This is a decent article and puts more perspective on it.
http://www.epi-eng.com/piston_engine_technology/bmep_performance_yardstick.htm

I've read the engine builder showdown engine made 233hp with the 2300 cam, but no mention of RPM. Lets assume it made 233hp @ 6500rpm, same peak power as the fk89. That's a bmep of 13.78, still a long ways from 14.6. If peak power was higher, then bmep was actually low than I've calculated.

bugguy1967 wrote: Hey, about that old competition 2332, 224HP was with a FK89. They used an experimental grind at the time that helped it produce closer to 235 HP, but it failed last-minute.

I haven't read about brake mean effective power in awhile, but I was pretty sure 15 bar N/A could be exceeded with a good amount of combustion knowledge.

Sun May 06, 2018 12:45 pm

I don't think any of the dyno tests I have tested with the belt on.

bugguy1967 wrote: Just read a new post. Pat says the engine had no alternator.

Sun May 06, 2018 1:00 pm

Yeah, I see what you mean. That engine seems like it'd need more rpm in order to produce what it did. Thanks for the link.

Sun May 06, 2018 1:41 pm

Belt on or off, that is still very very good numbers through 044 heads.
But as menthioned, the boundraries have really been pushed over the last 5-6 years.
In the other end of the scale 135 hp through stock valves was considered only for the top end tuners to achieve 10 years ago. Now we are pushing 145 in race engines.

Sun May 06, 2018 1:51 pm

Pat stood out among the rest way back when they did the engine builder showdown. At that time people were like "no way, how can he make 224 hp".

With his kind of resources and passion, im not surprised he is achieving 265hp 12 years later.

Sun May 06, 2018 1:59 pm

I'm not saying it's impossible to make 265hp from a 2332, just that at 7000rpms it's very unlikely.

In the the end, it's a tool. Put it in a car, see what it does.

Sun May 06, 2018 3:03 pm

jpaull wrote: Pat stood out among the rest way back when they did the engine builder showdown. At that time people were like "no way, how can he make 224 hp".

With his kind of resources and passion, im not surprised he is achieving 265hp 12 years later.
Yes I remember. - but similar numbers were pulled on this side of the pond about at the same time.
Without knowing I think Peter Shattock´s all out 1800 cc has one of the highest hp/liter numbers around https://www.youtube.com/watch?v=uiEk_sE4Yzs Just north of 250 hp if memory serves. But NOT VW heads. With MS230 heads.