The mad machinists who built a 920-hp V-12 nearly from scratch

[Hagerty]

Pete Aardema and Kevin Braun have worked together to develop some of land speed racing's most intriguing engines. They've built Chevrolet LT5s and adapted various racing cylinder heads onto vintage engines, setting dozens of records at Bonneville and El Mirage over the last 30 or so years.
https://www.hagerty.com/media/motorsports/the-mad-machinists-who-built-a-920-hp-v-12-nearly-from-scr...

[NATC]

Holy smokes that's a gas guzzler! I wish I had time on my hands to do a project like that. It's ironic that I work at an automotive testing center - https://natc-ht.com ,  but don't upgrade my vehicles.

[BMD4800]

In Motorsports, the cost of fuel is a non-issue. If it is, you’re in the wrong class.

But regarding your final sentence, why is it ironic that you test vehicles for a living but don’t upgrade them? I’d say that fits with the majority of Engineers, especially big 3 types. Individuality and independent thinking is largely squashed in favor of committee and group think. MAE courses from 1st year through graduate level are designed to reinforce this, tear-down paradigms, and get buy-in to the corporate direction. Sure, there are small skunk work groups and specialty teams within each, but these are no less immune.

[warrene]

Fun to fool with but ... I wouldn't take it as a gift, not if I had to feed fuel line. Would no doubt beat a Tesla on take-off, heck of a price to do it tho'.

[Smileamile]

American “enginuity” at its best! You’ve got to love guys who march (“rev") to their own beat (“sound"). Having lived in Asia and Europe over the years, I rarely met guys like these (Germany being the exception). What a great story! Thank you...

[MrBill-1943]

Leave it up to a couple of old guys who love cars to build something like this in a garage as opposed to a fancy lab. I just love it and would love to hear it start up live just like back in the day at the Cape when we saw a Saturn 5 blast off...now that was a ROAR! Congrats guys loved the story

[dooscoop32]

And Chevrolet just unveiled their newest crate engine. It is the 632 cubic inch Big Block making 1004 horsepower. And they are managing this with only eight cylinders and without any power adders such as supercharging, turbocharging or nitrous oxide.
https://www.motor1.com/news/541869/chevy-zz632-crate-engine-debut/

[TonyT]

And it's not a one-off V-12 built by a couple of guys with an imagination. Apples and oranges...

[fotogmike]

Chevy's new crate engine is 10 liters. This one is only 6.

[TonyT]

Can you ask these guys if they would adopt me? I would love to learn a quarter of what they have forgotten!

[mfp4073]

I'm with you! These guys could show us a few tricks I'll bet.

[SuperDeLuxe]

Wish there were more V-12s and 16s being built. What a shame to see the ICE age coming to an end!

[RodneyRacer]

Air intake and box is critical. Air moving in at high speed has to be managed so it is equally feed to each intake. There are a lot of intake ports on that thing. Think about air movement that includes Venturi effect (vacuum) and the Bernoulli effect (pressure and velocity) and how all that works out under that engine cover as the speed increases, changing density and pressure. I know of one Salt Car that mounted and pressure gauges in the air box under hood to measure pressure differences which helped with making a few new air boxes for more equal flow. Yep, the stock production body car was able to make a one-way pass at 235 with a small block Chevy. 219 both way average some box adjustments made the difference on the second pass.

[Brandan]

Indeed, Aardema and Braun have learned that the air tends to pack the rear of an intake box at high speed.

[BMD4800]

The air box isn’t the issue, as it is the position. Most racers either have it pull from the cowl, not the airflow side, or have a metered baffle to prevent an overpressure situation.
But it gets even more complicated, as the airflow over the stacks changes. Micro vortices at the edges, along the inside of the scoop and at the rear can create a reversion and drop pressure, even cause airflow to stall. Think of the SR-71 engine cone design.

The guy who was talking about thermocouples in each header primary is on to the answer. OHC cross-flow engines at 9500 rpm have very short signal (reversion) pulses and are more accurately akin to sequential constant flow events.

[Tinkerah]

BMD4800 - I imagine every feature of the airbox having tremendous effect on intake distribution at those speeds and resulting pressures. Wouldn't it have to be considered as an intake manifold? I was thinking O2 in each primary; couldn't the computer manage the mixture for each cylinder in real time? I think I'd rather correct a lean condition with more fuel rather than purging (wasting!) pressurized air. Unless imbalance is a concern. Just some musings from an armchair engineer....

[BMD4800]

The issue is the quality of the airflow, not so much the volume or pressure.   Fast moving, turbulent airflow from a scoop is worse than pulling from a high-pressure  or static pressure duct.  

[dooscoop32]

@TonyT
So what??

[TonyT]

Not sure I understand what you mean. Talk to me.

[Oldroad1]

An air scoop centered atop a balance chamber with ports for each stack sealed with either seal rings or short rubber hoses. Just an idea that could work like a compressor tank for even forced induction.

[TransAm-forever]

Why not use an air scoop for each intake port? Or would the leading scoops block and diminish the air flow to the following ports?

[Maestro1]

I've never been much of a horsepower freak but these guys are amazing. Thank you for this.

[fotogmike]

Are you sure about the power numbers? Looking at the dyno graph, I'm following the red line and it looks like the power peaks at around 775 at 9500 rpm.

[SAG]

nearly from 'scratch',
Ha.
I've had customers, purchased "blue prints" for a non-existing motor.
Purchased & Filed for "patten",
Had it built.
That's from 'scratch'.

[Gary_Bechtold]

Pretty amazing thing to see done. A new V12 is a cool thing to see.

[brb]

Just awesome.