Small V8

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

stevehuckss396

Model Engineer
Project of the Month Winner
HMEM Supporting Member
Joined
Nov 19, 2008
Messages
4,932
Reaction score
1,680
Location
Sterling Heights, MI
Hello all!

I have hit a creative wall with the straight 8 so I have decided to put it aside and work on something else. This new project is something I have wanted to do for some time. I finally have the plans in good shape, well good enough to start. I like the size of the peewee V4 so i borrowed the 5/8 bore and stroke and will try to build a V8.

untitled-2.jpg



This V8 will be small by most standards. 5/8 bore and stroke. It will have splash oil system and have a coolant system. Unlike Peewee, It will have a more conventional head setup with valve covers. The block will be about 5 inches long with heads at 4.5 inches. I will shoot for 6:1 compression. The cam will be about the same as the peewee as far as lift and duration. Seems like a doable size for smaller equipment.

The down side is that I could only fit # 8 spark plugs in this one so I'll have to make my own. Also the distributor cap sold by Roy is too big so I will have to make my own. The ignition will need to be toned down to control spark.

It will be built using manual equipment and CNC equipment. I know that's a turn off for some but I didn't build a CNC mill so I could look at it across the garage. I'm hoping it will speed things along when making 16 rocker arms or 16 of something else.


The block is made from a 3 X 3 X 5 block of aluminum.

DSCN2125s.jpg


DSCN2127s.jpg


DSCN2132s.jpg


DSCN2137s.jpg
 
I'm really looking forward to this build, Steve, as I intend to build a small gas powered V8 once I have developed the necessary skills. I have learned a lot from your WIP threads so far, and I look forward to learning plenty more.

What type of aluminium did you choose?
 
Hi Steve
Nice beginnig on the V8. I'll be watching this build, for sure ;)
I have missed the stright 8,but I'm sure you will be finnishing it when you comes down from the wall :big:

CS
 
That is a monster of a project. Can't wait to see more pictures! Thanks for posting.
 
T70MkIII said:
I'm really looking forward to this build, Steve, as I intend to build a small gas powered V8 once I have developed the necessary skills. I have learned a lot from your WIP threads so far, and I look forward to learning plenty more.

What type of aluminium did you choose?

I used 6061. 6061 is good for every part of a small engine. I might use some 7075 for the pistons but everything will be 6061.
 
crankshafter said:
I have missed the stright 8,but I'm sure you will be finnishing it when you comes down from the wall :big:

I have made some motor mounts but have not put up pictures. I have to work out the ignition. I can make up my mind so i'll let it bake in my head for a while. I will make that thing run.
 
Well we are off to a bad start. I screwed up the block so i'll have to have it welded up before i proceed.


I thought that starting on the heads would take my mind off things. I worked on getting the blocks squared up and machining them to the correct shape.


DSCN2151.jpg



DSCN2153.jpg



DSCN2154.jpg





While the heads were being worked on the CNC machine was chopping away at another piece of the puzzle. In the time it took to make 2 blanks for the heads, the CNC spit out the oil pan.

DSCN2148.jpg



DSCN2150.jpg




Here is where i'm at. Bummer about the block.

DSCN2156.jpg

 
First thing I did was mill the valve cover surface and create the pocket.

DSCN2159s.jpg



The holes are drilled on the bottom and a small water passage was milled in the surface.

DSCN2161s.jpg


DSCN2162s.jpg




The exhaust port surface is prepared but will need to be drilled to the port after the valve cages are installed.

DSCN2165s.jpg




I still need to do the bottom to create the combustion chamber and I also need to do the intake surface. Hopfully tomorrow! It's starting to look like a head.
 
stevehuckss396 said:
Well we are off to a bad start. I screwed up the block

Apologies if this is a reminder of a boo-boo...but I don't understand what the boo-boo is. What needs to be welded up? The parts look awesome to me.
 
zeeprogrammer said:
Apologies if this is a reminder of a boo-boo...but I don't understand what the boo-boo is. What needs to be welded up? The parts look awesome to me.

Made a bad cut on the block after the last photo was taken. Just need to touch up 2 surfaces and redrill one hole.
 

Awesome work Steve!

Looking forward to this one.

 
Ok, you got my full attention Steve. This is turning out to be a pretty awesome engine.

This is your design?

Kel
 
kcmillin said:
This is your design?

Yes and no. I took some peewee and threw in a dash of nitro V8 and a tea spoon of big block chevy and walla.

I liked the size of the Peewee but I had to stretch the block to make the heads work. I had some plans for a nitro V8 that had a pretty good head, so i reworked it (alot) to work on the block. Then everything else I drew for this engine specifically.
 
Nice to see a new project start and especially one from you. I see Alibre features heavily and just the plans alone are a big project so well done.

I understand the comment re CNC and I go hot and cold on a mill for the future. Could you annotate any picture if its done by CNC? Take it as a compliment about telling the difference! If you want any help re camshaft design and a cutting chart them let me know....I know this chap......oh.. forgot, its you!

Looking forward to the build Steve, from design to running will be a great achievement.
 
lookig fantastic so far
will be watching :)
 
Hi Steve,
It looks like you're making great progress on this build already. Are you going to be making an intake manifold similar to the one on your other engine? I silver soldered mine out of two pieces and it worked quite well.
George
 
gbritnell said:
Hi Steve,
It looks like you're making great progress on this build already. Are you going to be making an intake manifold similar to the one on your other engine? I silver soldered mine out of two pieces and it worked quite well.
George

Going to try a one piece. If that fails . . . .. We'll talk.
 
Back
Top