Inliners International Forums General Discussion Blown and Injected 4 valves per cylinder

Hello everyone, this is my first post and I would like to share an idea a few friends and I have had. (I am also not sure where to post this as it is a Performance/EFI thing so I will make 2 posts one in Performance and one in Blown and Injected)

If you do not care to read my story... please skip the following paragraph

Well, it all started in high school when I was your typical V-8 crazy not actually knowing much but loving cars kid... After my first car died (a 1994 Oldsmobile 88) I began searching for something cool, something with a big V-8 something American and from the 60s... After realizing limited funds I settled for a 1966 Chevelle with a 230 straight 6. Fast forward 4 years and now I am in College(Mechanical Engineering) working in my Engineering departments Machine/Fabrication shop. The 6 is a true workhorse engine never actually breaking more than say wasting 30 min of my time on the side of the road fiddling with things to get it to run. However, I came across a deal I could not refuse for 300$ a 1985 Toyota MR2... After a quick rebuild and many hours cursing and wishing the Japanese had taken any consideration into people who work on their own cars... It is up and running. It also came with 2 spare cylinder heads. NOW HERE IS THE INTERESTING PART.

What if I scaled up the peppy 4AGE(1.6L, 4 valves per cylinder, Dual Over Head Cams, 112hp, 98ft-lbs tq, and a redline of 7600rpm) to the 230(3.8L)?

Has anyone tried something like this?

MY boss, who has been in the CNC business for 20+ years, has agreed to help me out.

I have already started hacking the 4AGE head to pieces(good old band saw) and will start the process of modeling it in AutoCAD Inventor.

Megasquirt will provide the EFI and Distributorless Ignition into the equation.

What I need to know is what will take a Chevy 230 to 7000+ rpm, rods, pistons, cranks, etc?

What does it take to cast a 40-50lb piece of Aluminum?

Any Input on the matter will be greatly appreciated

Some other items that will need to be designed are the cam drive/front cover assuming DOHC. The oil pump drive will need to be addressed as well since it runs off of the bottom of the distributor. With the stock cam removed the lifter bores would need to be blocked off to maintain oil system integrity.

As far as casting goes if you have unlimited CNC resources then fabricating the patterns can be done. You will need to find a good aluminum foundry to do work with. The foundry can advise you on where the risers and vents need to go.

Most likely this would take 2-3 itterations before you have castings that are good enough to start machining.

Once you have the head casting ready, then comes the entire valvetrain which most likely would be custom designed. Also the short block would need good pistons and rods to support the target rpm.

Rough estimate this will be a 3000-4000 hour project before your done to the point where you have a running engine with enough testing to validate the design with parts ready for production.

Consider the time investment, is this a one off or are you considering producing parts? Then the ROI has to make sense with a target sell price that folks will pay. If its more than $2500 for a complete head with cams most likely your market will be under 20 set.

That is a pretty massive undertaking, considering all the additional components that are also going to be required to complete the total package. Just make sure the end result yields a better head than what you started with. The factory siamese head can be made to do some pretty spectacular things when ported and have the "lumps" installed. Good luck with it, and keep us informed with your progress should you decide to continue on with this.

For now a one off(maybe a 2 off for a friends 240z) is what I am looking at. I have always been a "DIY" person. Hopefully with my bosses and other faculty support. Just the satisfaction of poping the hood at autocross and people seeing a "24v DOHC EFI" straight 6 that revs to heaven, and when they ask me where I got it "oh, I built it."

As for cam gears I plan on finding a nice sized timing belt and making some pulleys on a CNC.

Did not consider that the oil pump runs off the dizzy any ideas?

Valvetrain, there was a smallblock chevy with lotus designed 4 valves per cylinder in the 90s with very a similar bore to my 230(smallblock bore = 3.9in, 230 = 3.875 + .030((for rebuild))) I need to do some checking but I could design the Head around those valve sizes.

I am still in the "is this actually possible" phase so I am trying to gather as much info as I can.

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Did not consider that the oil pump runs off the dizzy any ideas?



[/quote] You can go external with the oil pump, and use a belt drive like most dry sump systems use. You also will need to consider how to route oiling to the head for the cam journals and other components that will require it. You might consider the newer 4.2 trailblazer engine/head for a comparison. It already shares a similar displacement to the 230 engine, and the valve sizes, port volumes and combustion chamber size and shape could save you a lot of guess work. They are dimensionally similar in length, and intake and exhaust manifolds could even be made to work if you pattern your design to use them, saving you additional designing and work developing those pieces. Try to utilize as many components that already exist from other engines.

[/quote] You can go external with the oil pump, and use a belt drive like most dry sump systems use. You also will need to consider how to route oiling to the head for the cam journals and other components that will require it. You might consider the newer 4.2 trailblazer engine/head for a comparison. It already shares a similar displacement to the 230 engine, and the valve sizes, port volumes and combustion chamber size and shape could save you a lot of guess work. They are dimensionally similar in length, and intake and exhaust manifolds could even be made to work if you pattern your design to use them, saving you additional designing and work developing those pieces. Try to utilize as many components that already exist from other engines. [/quote]

With the Trailblazer 4.2L are you talking about 4.2L Vortec? I believe those already have 4 valves per cylinder and make about 290 hp?

I would love to see one of those heads. However, I can not find much info on them, or even a picture of one off of the car... It would be pretty hilarious if they shared the same bolt pattern.

as for things like intake, exhaust, and other misc components I plan on making most things that will not be insane. My shop has an abundance of aluminium sheet metal for an intake(plus that way I can do all that fun number crunching and come up with optimal runner length, shape, and of course some Computer Aided Engineering fluid dynamics) Exhaust can be made by piecing sections of stainless mandrel bent tubing.

If anyone knows where I can find info on the chevy 230 blocks(actual schematics and such) or, more info on the 4.2L votec?

You can see if efi-diy on the board here can post some pics of his engine he is building. It would be neat if these engines shared the same bore spacing and other things with the early engines. I think its the same engine as the 4.2 Vortec you mentioned....