Technical Game over for double hump heads?

This was probably decided years ago and I just never got the memo. In the last couple weeks I have pulled apart a couple engines I was running with early heads. One had 461s, the other 441s. These were on cl***ic trucks that aren’t daily drivers, low miles on both engines. Severe exhaust valve recession on both, both ran poorly obviously. I know the deal about bad gas and hardened seats, but I got away with this for years, and now clearly that’s over. Maybe the fact that I used to run cams with lots of overlap and rich jetting helped, maybe the gas is that much worse. Based on my dad’s bad experiences with valve seat inserts in flatheads I’m a skeptic. Sometimes you hear that they’ve figured it out finally, but I don’t know. And I’m not running racing gas. So is it down to Vortecs and aftermarket for non-show cars? I still have a pile of 462s, 461s 487s, etc. trying to figure out why.

 

I still run camel humps on all my small blocks. With hardened seats, I have not had a single issue with my heads.

 

Running a set now.
Drove it today. No issues.
Had hard seats installed 5 years ago. Over 30k miles.

 

My 3W has an old set of Mondello 461 heads that a friend had on his engine in the '60s. When I built the 360" engine in the early '80s I had a local machine shop install hardened seats, guides, springs and retainers. If you have access to a quality machine shop I'd personally have them rebuilt. Depends on how much I'm sure.

 

My last set of 462s are at the engine shop getting rebuilt right now. They'll be getting hardened seats, that is of course if nothing else is wrong with them.

 

I just spent way more money on a set of 462’s than I should have. Dad set a National record with them, so I figured I would pony up and do it. I had hardened seats installed.

 

I use them in my BB mopar iron heads, the last time the 12.5 motor was on the dyno it made 650 hp 620 tq seats have been in there since 1990 and seen 7200 RPM.

 

While we're on the subject, what is a normal cost for having hard seat installed in 462 heads? Don't include the cost for a valve job, guides etc, just the cost for updating the seats?

thx.

 

I really don’t know. I have $600 in mine for every thing and mine were decent.

 

Depends on where ya at.
My local guy built mine for $300.
+ the springs I bought.
He provided the guides and seats.
He also tossed in a set of valves for my old 882 heads I had.
He did another set for $350. That’s working the existing valves, new guides and exhaust seats.
Both hot tanked and surfaced.

 

Had a good set of 461s, took them to a reputable performance engine builder, wanted screw in studs, valve seats 2.02/1.60 valves and surfaced...told me to go buy a set of Dart Iron Eagles.

 

And there we have it. Kentucky ain’t California and every machine shop experience I’ve had here—or even heard about—was a tragedy. My next build is going to be a 406. I have 487x heads I was going to use, but even the bad machine shops tell me to get Iron Eagles as well.

 

If they can’t fix a seat I wouldn’t let ‘em touch a block

 

Exactly. I’ve been given the names of a couple of places that specialize in race engines. I’ve been told that won’t mess with these old heads, but they will do the block and crank, but they have a wait list

 

I think the problem with the hardened seats is when you go to a 2.02 valve. If you stay with the 1.94 it has more room for a seat.

 

I found a local guy that only does heads. He did a set of 882 casting heads for my kids vette and he charged me $300 including new springs. I asked him about doing a set of 461’s I have and he said they are typically $400 for everything including hardened seats. But, he does it in a shop in his backyard, so overhead is low. He does lots of heads for local roundly round guys as well as some of the street outlaw guys. I was very happy with his work and need to get my 461’s to him. Anyway, I would still rather spend money on these old heads than run something newer.

 

That’s pretty cheap Jeff.

 

Usually costs me around $600 to do camel hump heads with new valves , guides and hard ex. seats. That does not include cutting em for screw in studs and guide plates... My machine shop said they would rather not do that anymore so I made my own jig and do it on a bridgeport. It doesn't make sense to use them anymore unless you are doing a vintage build.

 

He’s not an engine builder but an engine ***embler, there’s a big difference…

 

A buddy had the same experience. Wanted a set of double humps built for his car. Machine shop told him go buy a set of aftermarket. Don't waste your money on these heads.

 

Cost of machine work on them versus a different set of heads. That's the tradeoff. I have a few sets of double humps on the shelf, most double humps I find have been beat to death.

If I can find someone like @guthriesmith did - I'd have them worked up.
Good call on circle track guys, farmer/racer in my hometown did heads for claimers 20 yrs ago, may have to look him up. I doubt he sold his equipment.

 

One of my trucks is already back on the road, some here may say an act of blasphemy was required. Pulled a set of Vortecs off a ‘98 Tahoe several years ago. Got them for $35 on half price day at the pull-a-part. Lapped the valves, installed new seals. Sat on a shelf a long time. Eventually got a Vortec specific intake at a swap meet, still with nothing in mind. Until this week. So far I’m impressed. They are factory GM parts, did it all myself with the same “techniques” I’ve been using since high school, never darkened the door of a machine shop. Whatever it takes.

 

My machine shop guy must be different.
He’ll build whatever you want.
Replacing with new makes better sense. But so does driving something new compared to the old junk we focus on here.
But, I got to drop off a flathead block for my son.
Yea, I told him he could get 2-3 times the hp out of something else cheaper but non of those options were a flathead.
Darn hard headed kids these days.

 

No, a realist and a pragmatist that "***embles" NHRA cl*** racing engines...

 

Some shops are performance oriented shops.
Dollar for dollar, suggesting new heads is a better option for the customer. These guys could care l*** about a “look”. It’s function over form.
The shop I use mostly is a small, one man operation. Builds local round track stuff and lots of tractor stuff.
The equipment is ancient, the shop cluttered and always busy. He builds whatever ya drop off.

 

This is eggzactly what we experienced here locally. I gave my dad a set of Camel Hump heads he was going to use on his 56 and got the magic $600 quote. They bare, cleaned and ready to machine...............we are just going to sell them at our next swapmeet.

 

I've got 14,000 plus miles on my rebuilt SBC camel hump heads. All heads worn enough get new seats, valves and guides replaced, and that's not some new technology that's not been tested and done for decades. It works great and never a reason to be concerned or hesitant to have done.
My heads have hardened seats, iron guides, and stainless valves. They're basically a completely new head in an old casting. My local machine shop just did another set for me about a year ago. All the above was done, plus screw in studs, guide plates, new high lift springs, also added. Cost was $550.

 

It's been a couple of years since I price shopped, but the last time I checked the lowest price for aftermarket heads was about twice the price of rebuilt double hump heads. I picked up a set of rebuilt 461's a year ago at a swap for $300. The guy who builds race engines will advise you to buy aftermarket, because he's focused on performance per $, not nostalgia.

 

Luckily I have all the equipment at the college to do my own heads, seats, guides l and surfacing. The parts are cheap, and it’s easy machine work.

 

Of course early hemis came with factory hardened seats. And forged cranks. And ***y valve covers.