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davidmij
01-04-2012, 11:22 PM
I found a set of rebuilt 390 heads for $300 that I am thinking of buying as opposed to having mine rebuilt. Getting mine rebuilt with hardened seats and 3 angle valves will run about $450 a pair. Here's the difference, the ones I currently have are from a 67 LTD and numbered C7AE-A. The ones that I can buy for $300 are numbered C4AE-6090G. The guy selling them said something like they are a "poor mans cobra jet head"(?) He said they have bigger exhaust ports and thus will give better performance at higher RPM ranges when flow is at its maximum. Anyway, I found this link that has some info;
http://mustangtek.com/heads/Heads.html
I'm not car savvy enough do figure it out - can anyone enlighten me as to whether one is all that much better than the other and if they should work OK?

Thanks, Dave J

simplyconnected
01-05-2012, 01:51 AM
David, in my book cast iron heads will always be just that. I don't care what you do with them, they just don't perform as well as aluminum.

Look at what the new engines use and consider why they get 250,000 miles out of each one.

Heads are THE most important component in an engine. You might save money on some parts but NEVER go cheap on heads.

Aluminum heads transfer heat much better than cast iron,
they eliminate ping and knock,
they allow higher thermostat temps to raise the boiling point,
higher temps also allow better burn which saves fuel,
aluminum heads are LIGHT WEIGHT over your steering wheels, allowing faster turns with less oversteer.

Get a set of Edelbrock Performer heads. They already have stainless valves, new springs and hardened seats. - Dave

davidmij
01-05-2012, 09:21 AM
Yes, that would be nice Dave, but this is just a RatRod car that's gonna be driven a couple hundred miles a year. Besides, aluminum heads are way out of my price range.
I just want to know if the two sets of heads I listed are comparable and compatible. If so I can buy the ones for $300 and sell my old ones.

I just bought a 4 speed top loader close ratio big input and output shafts #RUG-AJ, included a Lakewood Bellhousing and block plate - that set me back a bit more than I wanted. It looks brand new inside and out and I've had a hard time finding a tranny in state.

Thx, and let me know if any of you can tell me anything about the head numbers I listed.

- Dave J

scumdog
01-05-2012, 01:15 PM
Yes, that would be nice Dave, but this is just a RatRod car that's gonna be driven a couple hundred miles a year. Besides, aluminum heads are way out of my price range.
I just want to know if the two sets of heads I listed are comparable and compatible. If so I can buy the ones for $300 and sell my old ones.

I just bought a 4 speed top loader close ratio big input and output shafts #RUG-AJ, included a Lakewood Bellhousing and block plate - that set me back a bit more than I wanted. It looks brand new inside and out and I've had a hard time finding a tranny in state.

Thx, and let me know if any of you can tell me anything about the head numbers I listed.

- Dave J

Hah!
Back in the 80's I bought a big-input Top-loader while in your state, it was from a private wrecking yard yard near Gallup, you could just see it from the I-40!

Now using it in my '37 Ford coupe project rod.

redstangbob
01-05-2012, 02:52 PM
The C4AE-6090G heads will be fine, check the 'thumbprint' to get an idea if they've been milled to death. Do some looking around at the FE website http://www.network54.com/Index/10214 anything you want to know about FE heads can be found there. Good luck, Bob C

davidmij
01-05-2012, 04:43 PM
That's pretty funny Tom, never would have imagined anything from Gallup NM ever ended up in NZ. Sure would love to visit there one day.
The one I have is a close ratio out of a 69 Torino, from what I see online I think it's fairly rare because it's listed as an option for that year, the wide ratio was standard equipment.

Bob, what do you mean by "check the thumb print"?

The heads were still wrapped in plastic and the plastic looked pretty old. The guy said they had been sitting on his shelf for several years, he said the springs were heavy duty or something like that.
I mostly want to make sure I don't give up any HP or torque if I buy them and switch. The 390 I have (with the 4 barrel carb) is rated at 315hp and 427ft lbs. It has a single exhaust pipe, I figure some headers could up that at least 25hp. Not sure how much of a tire spinning hole shot I'll get with a 3.10 rearend and a close ratio trans, but I can always put on a better intake and change out the pumpkin to a 3.73 down the road as money and time permits.

We used to have some really good old junk yards in New Mexico when I a kid back around 1975 - you could find tons of stuff.

thx, Dave J

redstangbob
01-05-2012, 04:56 PM
This should help with the thumbprint http://www.network54.com/Forum/74182/thread/1170601460/1170612683/cylinder+heads Good luck, Bob C

davidmij
01-05-2012, 05:00 PM
Indeed Bob, even I can check that.
Thanks a ton!

gaffney1951
01-05-2012, 07:35 PM
what you have to watch with seat replacement on FE heads is that it is VERY easy to run into the water jacket and you won't know if it is problematic until you run them. Generally not needed for street use with unleaded gas unless there is serious degradation of the seat. You will probably be better off having your heads re-worked and use the factory seats. Mike

davidmij
01-06-2012, 10:12 AM
Thx Mike, I had to google "water jackets".
So you're talking about IF I were to have my current heads rebuilt and have hardened seats put in the welding can impede the water jackets around the valves??

I called the guy selling the heads again, he said they have good finger prints - he said they weren't milled, just resurfaced. They are still wrapped and taped up in the plastic from the shop that did them in Albuquerque. They have the paper from the shop with the receipt still stuck on the plastic. The guy tore some of the plastic back so he could show me the large exhaust ports. Still don't know what he means by "poorman's" CJ heads??

Anyway, I think $300 is a fair price from what I've seen on line. They aren't hardened seats, just stock, and they have the single valve seat - that shouldn't be a problem if I'm just going to drive them a few hundred miles a year.
Yes, no?

Steamboat Springs is the same altitude as here in Los Alamos, actually Albuquerque is a mile high, just like Denver (not many people know that). Any advise for altitude adjustments on my car?

thx, Dave J

gaffney1951
01-06-2012, 03:38 PM
the original exh seats are cast in the head and need to be machined for inserts. When cutting holes for the inserts is were you can run into problems hitting water. Not sure which carb you are using, but if it was setup for sea level I would try dropping down 2 steps on the primaries and see how it likes it. And then try the same routine on the secondaries. the best way to do it is with an O2 meter on a chassis dyno, but that can get pricey fast. Mike