Inliners International Forums General Discussion Engines 292 with a possible 194 head??? 3788380

Is it worth it to install this head? I think it is a 194 which has been worked on. It has 1.94 intake valves installed. This is going onto a 292 for a 1966 C30 dually flatbed. We did purchase an OFFY intake with a holley 390 2 bbl carb and installing some shorty headers. It will have the stock cam as of right now. We did purchase some screw in studs.

Also I do not think they can take lump ports because of the work done to the bottom part of the valve.

We did some pretty extensive dyno testing several years ago and found the 194 head made less power and torque than a comparably prepped open chamber head in every test that was performed. Sages for decades have claimed miracles by using the 194 head, but professional head porters and engine builder like Kay Sissell mentioned in his own catalog that "a 194 head only belongs on a 194 engine because of severe shrouding that can't be corrected!" I'm not saying Yea or Nay, just pointing to the evidence and research that is out there, so you can draw your own conclusions.

This is for my son's c30 dually. He is 17 years old so I really do not not want his truck to have a lot of HP. I would think 200-250 might be enough for him to drive on the street. Also, I think the current head on this truck has a valve problem. I am going to install this one and maybe redo the other one at some point. Right now, he is only into it for 200.00 so I guess that's not too bad (got it checked out at a machine shop). This is not his daily driver.

So it is 194 head??? I was not sure. It does have 1.94 valves in it.

Its looks like it, but a casting number check will confirm it.

Does it look like the head was worked on? Looking at the intake ports...

Did these come with 1.94 valves?

No, they all came with 1.74" valves. The ports have been ground on a little but, maybe to smooth out some rough casting.

Okay, thanks!

Jim,
Can you give a few more pics. One straight over the head and show a few chambers.

It looks like someone put larger valves in that head. I would install the bolt in lump kit since the bolt bosses are cut. Every little bit helps.

I can get some more pictures tonight.





So I could install a lump port on this head? Would I need to remove any more material?

That head is a small chamber that has been worked on. New guides, hardened seats, larger valves (maybe 1.94 intakes) Opened the chamber around the intake valve. Personally , I would open the chamber more around intake valve on spark plug side.
All in all, this looks like a great head. Install the lump kit.

Some material may need to be removed around the lower bolt bolt in the floor of intake port, but not much.

Okay, we can handle that.

I will buy a set of lump ports from your ebay store soon. He picked up the head at a swap meet for 80.00. Pretty smart for a 16 year old to grab it when he saw it. At the same time I picked up a set of headers trading off his old large Rochester carburetor.

I had it pressure tested and magnafluxed.

The valves and springs look fine. I bought new seals for it. Plus have poly locks and screw in studs for it.

The valves are 1.94. I measured them to check the size to order the lapping tool.

How much material can we remove? I have the inline 6 performance book.

You need to watch the install video. It show what metal needs to be removed to put in the lumps. In your case, right in the area around the lower intake port bolt boss. It just needs flattened out.

Your head is also one of the oldest ones. It has siamesed exhaust ports also.

Is Siamese exhaust bad or good? we do have a set of headers for it.

It is not as good, but that is what you have. You will not notice a difference.

Is it worth it to install lump ports with the stock cam? He will be running the SM420 transmission and 539 gears for now.

This is a truck he will only drive occasionally as he probably cannot park it at his school.

Maybe down the road he can switch out the cam.

The lumps will help, even with a stock cam.

The lumps will not help a head with stock size valves.

The valves in your head are 1.94, stock is 1.72.
Notice the dyno chart at bottom of this link. It shows a comparison of a stock head/ cam to a built head with stock cam.
http://www.12bolt.com/65279inline-cylinder-head-flow65279.html

Interesting how the lumps detract flow at low lifts and then kick in as the lift increases. Similar to cam duration trade off in relation to RPM.

That may have been something with that particular head. But more flow does not always produce more power. But look at the dyno sheet. More torq at almost every rpm.

When the valve starts to open, piston speed, flow rate and velocity is relatively low, and the charge is largely "glued" on to the floor, the shortest distance between the two points - the carb and the cylinder. So sticking a lump on the floor would make for a longer, circuitous path for the initial charge.

On the other hand, at high piston speeds and high lift the charge is swiftly moving and the inertia of the fast-moving mass packs the charge up against the roof of the port. This is when the lump helps funnel the charge into the cylinder at high velocity with a minimum of turbulence.

So one can infer that a bigger valve - and a higher lift cam - will amplify the effect of lumps.