XXO/BVGC '38 Chevy Coupe Build

[Pete1]

Thanks guys!

 I keep wanting to fix things in FRONT of the tires- guess everyone is right- I AM back asswards!

The air in front can be diddled with also.

[maguromic]

How you close the air behind you is very important, but what you do in the front also influences how that air is going to close behind you.  Buddy, you are doing a fantastic job on your car, and I am sure by looking at all the details you will reach all your goals. I am also glad that my friend was able to help, he is really a closet salt junky.  Tony

[38flattie]

Tony, thanks again! I'm really looking forward to his input, and making the changes.

The engine is coming out of the machine shop today, so look for updates real soon!

[maguromic]

Buddy, He is a great guy and I think at last count the cars he has pened hold about 25 records with the majority over 200.  Tony

[38flattie]

Tony, I'm very excited about his participation-thanks again!


All right, let the fun begin!

Dale started port matching the top 'girdle' plate today. The top plate will serve a couple of functions- one is to tie the engine sides together, so that we don't 'split the engine. The other function is to give us a good way to bolt the intake and exhaust to the block.

[Milwaukee Midget]

Buddy -

Every single piece you bring to this build is just mindboggling.  This is like building a Tomahawk missile out of a flintlock.

I can't wait to hear it!

[Tman]

Buddy -

Every single piece you bring to this build is just mindboggling.  This is like building a Tomahawk missile out of a flintlock.

I can't wait to hear it!

I prefer my Flintlock! But the hardware here is some serious cool stuff!

Buddy, you get bored with doorslammers just let me know how much room we need in the lakester

[maguromic]

Buddy, That looks great, I cant wait to see you guys run that beast.  Tony

[Peter Jack]

This is a fascinating build from a really talented bunch of guys. Keep up the great work.

Pete

[BoredAndStroked]

Intro:  From a Fellow FlatCad Team Member

Hey Guys . . . just thought I'd introduce myself . . .  I'm 'Dale' that has been working with Buddy on the FlatCad engine for the last year and helped get the car on it's 'shakedown' runs at SW in August.   It is really exciting to be at the stage where I am down to the details, working through the final porting work and to start putting the engine together.  A tremendous amount of custom design/engineering and manufacturing has gone into this beast - top to bottom, everything has changed from stock.   Just wait until you see what this thing looks like in 'Full Dress'! 

If anybody has any technical questions on the engine design or build, feel free to ping me - will share what makes sense.   Buddy and I have been willing to share just about everything we're doing (we keep a few things in our pockets, but not many).   The whole Bonneville community has really embraced and helped us - want to give you ALL a big thanks and give back whenever possible.

I plan to complete the port matching and contouring work this week and get into the detailed lower-end work.   I'll make sure that Buddy has all the pictures he needs to keep the posts alive and up to date.

Have a great week!

B&S

[Elmo Rodge]

Good morning Dale and welcome to the forum. It was good finally meeting you at Speedweek after all these years.  I'd love to sit and chat but I'm heading out the door for Cook's Shootout.  Later. Wayno

[Tman]

Welcome Dale!

[38flattie]

One of the concerns I have is the cam selection. There really isn't any info out there on these engines, so the selection we made is really the proverbial 'shot in the dark'.

When I was on the salt, I was able to speak to several guys running vintage engines. The name Dema Elgin came up time and time again.I just had a long talk with Dema, about engine details, our goals for the engine, etc.

To make a long story short, we're going to ship the cam and a couple of lifters to Dema. He's going to plot it against his recommendation, and let us know where we are. I have another blank, so if it's needed, he'll grind us another cam.

[Freud]

Just like women and shoes, You can never have too many camshafts on the shelf.

Order more blanks.

FREUD

[Milwaukee Midget]

One of the concerns I have is the cam selection. There really isn't any info out there on these engines, so the selection we made is really the proverbial 'shot in the dark'.

When I was on the salt, I was able to speak to several guys running vintage engines. The name Dema Elgin came up time and time again.I just had a long talk with Dema, about engine details, our goals for the engine, etc.

To make a long story short, we're going to ship the cam and a couple of lifters to Dema. He's going to plot it against his recommendation, and let us know where we are. I have another blank, so if it's needed, he'll grind us another cam.

Thinking out loud - throwing out a few thoughts - and, of course, it's easier spending your money than mine. 

Stop me if I'm off the rails

Despite these great looking ports, it is an arduous flow path, both in and out of this monster.  Flow testing the block would likely get you some additional info that your cam guy can use. 

I'm looking at the firing order with respect to the exhaust opening and closing events (1 8 7 3 6 5 4 2), it looks like the 3&5 and the 6&4 could be a problem . . . Thinking overlap, your high pressure in the center shared exhaust port might not let you fully evacuate the 3 and 6 cylinders. 

As the 3 exhaust is closing, the 3 intake is beginning to open.  At about that same time, the 5 exhaust is opening, flooding the shared exhaust port, raising the pressure in the exhaust port and not permitting the # 3 chamber to completely evacuate - and possibly forcing some of the exhaust into the intake port of the number 3 cylinder (bigger valve, path of least resistance).

Some of the interaction might be able to be minimized by designing timing events into the cam that limit the duration that both the 3&5 and the 6&4 exhaust valves are open simultaneously. 

I'd also be looking at anti-reversion valve designs, if possible. 

I know you're supercharging this thing, and that negates some of the interaction.

By the way, Elgin makes some superior cams for the A-block, and I'm pretty certain he's familiar with some of the scatter pattern concepts.

Just riffing -

My 2 cents - worth about half that . . .

And I'm loving this build!