4 cylinder ohv engine plans

[gbritnell]

I have found 2 omissions on the plans for my 4 cylinder OHV engine. I am posting a picture of the additions for those who bought a set of drawings. I appologize for any inconvenience this might have caused. I don't have everyones mailing address that purchased these plans so if you contact me I will be more than happy to mail you out the new sheet.
Thanks,
gbritnell

 

[stevehuckss396]

Got it G! Thanks for the update!!

 

[gbritnell]

Steve, I have your address so I will be sending you out a sheet with the new dimensions on it.
gbritnell

 

[stevehuckss396]

Good deal! Thanks

 

[gbritnell]

I got the copies printed up today so they'll go out in Monday's mail. I have 6 names and addresses so if anyone else reads this forum and bought a set of drawings at NAMES just let me know and I'll send you the drawings with the additions.
gbritnell

 

[DickG]

I wonder if someone can explain. Looking at the crankshaft of a 4 cylinder engine like this one, the same as the normal full size ones, why are there always 2 pistons TDC and the other 2 "BDC"? Wouldn't it be better to "space" them 90º of each other? In this way one could have a power stroke at 90º intervals probably making the engine run more smoothly. At least it's what I think. Maybe it's easier to build them the way they do.

If they are spaced at 90 degrees it's called a 'crossplane' crankshaft. Yamaha use this configuration for their MotoGP 4-cylinder, 4-stroke, across the frame, engines. The sound is pleasant compared to the awful sound of a Harley. Best sounding engine of all times is the 1.5 litre supercharged, V16 BRM, closely followed by the V12 Rolls Royce Merlin.
DickG

 

[Charles Lamont]

A Deltic sounds pretty good too:



And the Cosworth DFV.

 

[johwen]

I wonder if someone can explain. Looking at the crankshaft of a 4 cylinder engine like this one, the same as the normal full size ones, why are there always 2 pistons TDC and the other 2 "BDC"? Wouldn't it be better to "space" them 90º of each other? In this way one could have a power stroke at 90º intervals probably making the engine run more smoothly. At least it's what I think. Maybe it's easier to build them the way they do.

The reason is simple, it is to balance the rotating motion two pistons going up balanced by two going down

 

[LSAGuy]

Yamaha builds one. Here's a video;



Do yourself a favor and turn off the crappy music for the first minute and a half or so.

 

[oliomio]

Interesting video, and thanks for the noise warning. Unfortunately I was a bit slow turning it off. Horrible!

 

[myerscw2]

Are these engine plans still available for purchase?

 

[gbritnell]

Hi Meyers,
Yes the plans are still available. Send me a personal email.
gbritnell

 

[myerscw2]

Ok. I just upgraded my membership today. Not sure how to send you a personal email....

 

[splodge]

I'm interested in a set of plans, but live in the uk. Do you have them in pdf format to save on the postage etc ?

 

[ruben]

hola donde puedo encontrar los planos del motor

gracias

un saludo

 

[Mike1]

I wonder how the Audi's 5 cyl engine's crank looks like.


Helder

See here. https://www.hemmings.com/stories/article/gimme-five

 

[cyborg45]

@gbritnell , are the plans still available? Apologies for the intrusion if this request is ill-timed.

 

[gbritnell]

Yes the plans are still available. Send me a PM and I'll give you my email address for the information

 

[gbritnell]

The plans are sent as PDF files and are in Imperial size sheets 8-1/2 x 11 which is close to Metric A4 I believe.

 

[L98fiero]

The plans are sent as PDF files and are in Imperial size sheets 8-1/2 x 11 which is close to Metric A4 I believe.

Is there a picture of the completed engine somewhere, I tried the link in post #15 but it didn't lead to any thread or picture.

I found a Youtube video