Reasonable cost (NOT cheap) street flathead engine.

[Pete]

I have had 4 calls in the last 3 months about what parts to put in a "better than average" street engine.
For what it is worth, here is what worked for us when we used to do an ocassional street engine. Other stuff would work but this was a good combo with what was and still is available for reasonable prices.
As with anything, costs vary with your skill as a trader, bargainer and scrounger.

==================

Formula for budget go fast street engine with mild manners.
To build this engine you must first have a reasonable knowledge of performance engines and be willing to do any work you can, yourself.
This is a parts list only. Not a "how to do". These parts if assembled properly will produce a 200+ hp naturally aspirated street engine that will run on pump gas. This has been dyno proven.

Parts required:

8ba block. 3 3/8 bore.
4" Merc crank stroked to 4 1/8 with EARLY type cam drive gear and slinger.
One front crank damper as needed to match ignition clearance.
One set each of rod, main and cam bearings.
Reconditioned and shot peened 21A rods if you can negotiate a price cheaper than a new set of SCAT rods. Weigh cost of 21A rods and bearings against SCAT rods and bearings. Go cheap, both are good.
Ross street pistons with pins. Specify FLAT TOP and ZERO DECK HEIGHT for 4 1/8 stroke.
Totalseal gas ported low tension rings.
The cam of your choice. The "lumpiness" will depend on how mild or wild you want the drivability to be. BE CAREFUL WITH YOUR CHOICE HERE OR YOU WILL BE CHANGING IT TO A MILDER ONE.
One EARLY type cam drive gear, bolts and lock plate set.
One set of reconditioned stock hollow steel lifters.
One set of 185 springs, retainers and locks.
One set of stock 8ba valve guides with outside knurled.
One set of 8ba stock valves. (lightened)
One Aviaid 4 stage dry sump oil system.
One dry sump pan with windage tray.
One set of Edelbrock or Sharp heads with filled domes.
One 4 carb Edelbrock intake manifold with "48" carbs.
One computer type Jacobs or MSD battery ignition OR one H&C magneto. (note: type of ignition will determine model of cam)
One set of 2 inch "W" type headers with center baffle.
One aluminum SBC flywheel. (cheapest way to go)
One Hayes diaphragm clutch.
Two copper big bore head gaskets.
One pan gasket set with crank seals.
One front cover gasket.
One ignition gasket if H&C mag used.
One lead plate if H&C mag used.
One set of SOLID copper sparkplug gaskets.

[Brian]

Whew!! you're right...not cheap!!

[Will D]

Is there any noticeable difference in how long a valve guide will last, knurled vs stock?

[Pete]

Originally Posted by Will D

Is there any noticeable difference in how long a valve guide will last, knurled vs stock?

This is knurling on the OUTSIDE to hold them in tight. They are installed with high temp glue and you never have to touch them again. When they wear out you install bronze sleeves.

[Will D]

Originally Posted by Pete

This is knurling on the OUTSIDE to hold them in tight. They are installed with high temp glue and you never have to touch them again. When they wear out you install bronze sleeves.

Thanks Pete. I read "outside" but skipped the brain apparently.

[21stud]

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This is it.
The "thing for flathead performance" can be found with these parts.
What's different from usual shopping list? Read carefully and it is clear.

[Tim Ayers]

Pete:

Curious on the dry sump choice for the street. How much of a ballpark difference does this make?

Thanks,

Tim

[uncle buck]

What starter do you use with the aluminum Chevrolet flywheel?

[Ol' Ron]

258, milled heads, Holley 1 1/16 carb Load a matic dist on 12 v. Very cheap street engine.
Gramps

[Pete]

Originally Posted by Tim Ayers

Pete:

Curious on the dry sump choice for the street. How much of a ballpark difference does this make?

Thanks,

Tim

Combined with the narrow low tension rings, 40 hp.

[Pete]

Originally Posted by uncle buck

What starter do you use with the aluminum Chevrolet flywheel?

Gear drive SBC starter mounted similar to stock SBC.

[Pete]

Originally Posted by Ol' Ron

258, milled heads, Holley 1 1/16 carb Load a matic dist on 12 v. Very cheap street engine.
Gramps

But weak....lol

[alanwoodieman]

Ol Ron--sound like a good, solid, inexpensive street motor from the man who would know

[Ford Freak]

Ok, I didn't see any prices. I know it's not cheap. So, what would (ballpark figure) an engine like this cost me? I allready have a excellent running 1950 8BA.

[Pete]

Originally Posted by Ford Freak

Ok, I didn't see any prices. I know it's not cheap. So, what would (ballpark figure) an engine like this cost me? I allready have a excellent running 1950 8BA.

All prices can be readily be had from parts stores catalogs or the internet.
Everything is currently available somewhere.

[Tim Ayers]

Originally Posted by Pete

Combined with the narrow low tension rings, 40 hp.

Interesting. Do you lighten the crank as well or just clean up the bob weights?

[Pete]

Originally Posted by Tim Ayers

Interesting. Do you lighten the crank as well or just clean up the bob weights?

That is up to the individual but stuff like that helps.
By the way, I know what you mean but cleaning up the bob weights will only make them look shiny.....lol

[Tim Ayers]

Originally Posted by Pete

That is up to the individual but stuff like that helps.
By the way, I know what you mean but cleaning up the bob weights will only make them look shiny.....lol

Haha. Yeah. Poor choice of words. Next time, I'm going to really work on the crank and knife edge the weights, clean and lighten it up as much as feasible.

[Pete]

Originally Posted by Tim Ayers

Haha. Yeah. Poor choice of words. Next time, I'm going to really work on the crank and knife edge the weights, clean and lighten it up as much as feasible.

Lightening the crank is actually very cheap because you can usually do it yourself as long as you understand the basics, BUT, it will generally add to the cost of balancing due to additional machine work.

[Yoyodyne]

Originally Posted by 21stud

This is it.
The "thing for flathead performance" can be found with these parts.
What's different from usual shopping list? Read carefully and it is clear.

I see 2 items that I don't recall being discussed here - the dry sump and the heads. I'm very interested in how well the filled chambers work.

[Tim Ayers]

Originally Posted by Pete

Lightening the crank is actually very cheap because you can usually do it yourself as long as you understand the basics, BUT, it will generally add to the cost of balancing due to additional machine work.

Yeah, I'm going to give it a try next go around.

[Pete]

Originally Posted by Yoyodyne

I see 2 items that I don't recall being discussed here - the dry sump and the heads. I'm very interested in how well the filled chambers work.

On an all out vintage circle track engine we get well over one hp per cubic inch.

[Bored&Stroked]

Originally Posted by Yoyodyne

I see 2 items that I don't recall being discussed here - the dry sump and the heads. I'm very interested in how well the filled chambers work.

There are a couple things to note in Pete's post:

1) The dry sump is something that is combined with low-tension total-seal or metric rings. The goal is to reduce reciprocating friction and overall "oil drag" in the lower-end. You need enough "stages" in the pump to really pull oil and create a vacuum inside the engine.

2) On a full-on racing engine, some may add a vacuum pump as well.

Obviously in order to run a dry-sump setup, you also have to have a dry-sump reservoir.

The combination of a correctly designed dry-sump setup, low tension rings, oil scrapers, windage tray, etc.. - results in the important extra horsepower Pete was talking about --> I believe he referenced 40. That is a LOT in a flathead - so you can see the value in all of this.

3) On filling the heads, I believe what he is talking about is to fill/remove the dome and run a flat-top piston with a tight quench.

In days past, one could get some of the head manufacturers to deliver heads without any of the dome work done - so you could do what you want --> run a flattop, run a pop-up flat-top, etc.. Not sure if one can get anybody to do this today, but it beats having to TIG weld the heck out of a "normal" head to get there.