427 Cobra Engine 1966

Excaliber · #1 (**permalink**) 10-27-2008, 01:59 PM

I would be interested in documentation that indicates a top oiler 427 was planted in an original Cobra. Could be, but it's news to me. The 428 was used for awhile and then Shelby switched back to 427's (after customer complaints). At any rate the Cobra most of us emulate is the S/C, only 30 or so being built of the approximately 300 total count. S/C, side oiler, stick a fork in it!

"Rumor has it", my favorite saying when it comes to nailing down Cobra history, is that nine of the original cars (later models not early ones) may have had a center oiler.

ng8264723 · #2 (**permalink**) 10-27-2008, 03:41 PM

There is no difference reliability wise b/t a CO and a SO. The only difference is bragging rights
chris

Excaliber · #3 (**permalink**) 10-27-2008, 06:42 PM

Reliability, hmmm, a relative term. Center (top) oiler rev limit is around 6000 due to it's inherent weakness of splitting the block at the main journal area. You can spin it higher, but it becomes risky. Side oiler is good for 9000 rpm plus because it is an inherently stronger block, that's why they use it for the SOHC version.

427's and the FE's series engines in general get a bad rap as far as reliabily issues go. They ARE a 100,000 mile motor and ARE extremely reliable when built and used within reasonable parameters. The original side oilers were putting out about 475 horse from the factory and were quite reliable. Today we see many builds exceeding 500 horse, the risk factor goes up accordingly. Stroke it, put in a wild cam, build it to 600 horse and rev the heck out of it and you will eventually break it! Of course thats true for all the modern versions of a side oiler block as well.

Side Oilers powered the GT-40's to a win at Le Man's, 24 hours of pedal to the metal. The FE series engines are certainly reliable and strong enough for even a hard core racer.

undy · #4 (**permalink**) 10-28-2008, 03:42 AM

Quote:

Originally Posted by Excaliber

Reliability, hmmm, a relative term. Center (top) oiler rev limit is around 6000 due to it's inherent weakness of splitting the block at the main journal area. You can spin it higher, but it becomes risky. Side oiler is good for 9000 rpm plus because it is an inherently stronger block, that's why they use it for the SOHC version.

427's and the FE's series engines in general get a bad rap as far as reliabily issues go. They ARE a 100,000 mile motor and ARE extremely reliable when built and used within reasonable parameters. The original side oilers were putting out about 475 horse from the factory and were quite reliable. Today we see many builds exceeding 500 horse, the risk factor goes up accordingly. Stroke it, put in a wild cam, build it to 600 horse and rev the heck out of it and you will eventually break it! Of course thats true for all the modern versions of a side oiler block as well.

Side Oilers powered the GT-40's to a win at Le Man's, 24 hours of pedal to the metal. The FE series engines are certainly reliable and strong enough for even a hard core racer.

Actually the inherent weakness of the center/top oiler had nothing to do with block splitting as both side/top oilers were cross bolted which took care of that problem. The non-cross bolted Fees had the high-rpm block failure problems, hence the desirability of the extra block webbing in the 428 Cobra Jet blocks and the later "ribbed" service blocks. I don't believe (not sure though) that the 66 Cobra's 428 PI motors received that extra webbing either. The chink in the top oiler's armor was the lack of priority main oiling. The center/top oilers received oil to the cam first. What was left made it to the crank, maybe. Minor oil starvation conditions caused catastrophic failures in the top oilers. Oil pressure (volume too) to the crank under all conditions was less than with the top oilers too. That's the reason where most will say, other than all out competition (meant to say severe track duty) the top oiler should survive just fine. Most performance engines today, to include my 6 bolt main LS7, receive priority main oiling. lessons learned....

DougD · #5 (**permalink**) 10-28-2008, 07:54 AM

Quote:

Originally Posted by Excaliber

I would be interested in documentation that indicates a top oiler 427 was planted in an original Cobra. Could be, but it's news to me. The 428 was used for awhile and then Shelby switched back to 427's (after customer complaints). At any rate the Cobra most of us emulate is the S/C, only 30 or so being built of the approximately 300 total count. S/C, side oiler, stick a fork in it!

"Rumor has it", my favorite saying when it comes to nailing down Cobra history, is that nine of the original cars (later models not early ones) may have had a center oiler.

Excal
I'd suggest revisiting this thread:

how many 427 cars had 427 ci engines

Jog your memory?

Repeating something that is not true enough times makes it fact? Sounds like our current presidential election. I for one would rather believe the esteemed Nedsel, SAAC's 427 Cobra registrar, who ought to know.

Once and for all, not all 427 Cobras had side oilers. Starting with 3101, 427 top/center oilers were produced first, 428s second, and finally sideoilers for the last group. (Not including the comp and S/Cs). "Factory records suggest the first few
33xx cars came with 428's, and then the swap to the 427 side-oiler was made."

"All comp cars and all SC cars had 427 SO
CSX3101 - CSX3199 427 TO
CSX3200 - CSX3299 428 PI
CSX3300 to the End 427 SO"

Excaliber · #6 (**permalink**) 10-28-2008, 10:05 AM

Thanks for that link Doug. From that thread Tom Kirkham says:

Quote:

All comp cars and all SC cars had 427 SO
CSX3101 - CSX3199 427 TO
CSX3200 - CSX3299 428 PI
CSX3300 to the End 427 SO

I would consider Tom, certainly Nedsel, authorities on the question of which and how many Cobras came with top oilers. It is difficult to nail down the numbers, but one could be lead to believe it is more than 8 or 9. A number which has been stated on different forums for many years.

While the side oiler offers superior main bearing oiling Keith Craft himself has noted the potential failure for the top oiler block to crack at high rpm. Not all top oilers had the cross bolted mains. I'd bet most of them do not in fact. Granted 9000 rpm for a side oiler is lofty rpm indeed and subject to immediate failure at that rpm. The SOHC engine was capable of such rpm in drag racing, but certainly NOT a sustained rpm number!

undy · #7 (**permalink**) 10-28-2008, 10:18 AM

Quote:

Originally Posted by Excaliber

Thanks for that link Doug. From that thread Tom Kirkham says:

I would consider Tom, certainly Nedsel, authorities on the question of which and how many Cobras came with top oilers. It is difficult to nail down the numbers, but one could be lead to believe it is more than 8 or 9. A number which has been stated on different forums for many years.

While the side oiler offers superior main bearing oiling Keith Craft himself has noted the potential failure for the top oiler block to crack at high rpm. Not all top oilers had the cross bolted mains. I'd bet most of them do not in fact. Granted 9000 rpm for a side oiler is lofty rpm indeed and subject to immediate failure at that rpm. The SOHC engine was capable of such rpm in drag racing, but certainly NOT a sustained rpm number!

The only non-crossbolted 427s I've seen was a couple odd ball irrigation motors that surfaced a few years ago over on fordFE.com. Has anyone else seen a non-crossbolted 427 FE??

Don · #8 (**permalink**) 10-28-2008, 10:30 AM

The narrative in the book mentioned below, from the author's ,George Reid ,viewpoint includes detail comments and pictures on all the BB regarding reliability, casting etc, Too lengthy to type , some very brief excerpts regarding 427:

" Undoubtedly the most desirable Ford high performance block going is the 427 because it shares nothing in common with the rest of the " FE " line up. It's high-nickel content gives it extraordinary strength "

" The earliest 427 blocks had the 390 High Performance oiling system. Ford soon learned that at high revs, the 427's # 2,3,4, and 5 main bearings could sometimes become oil starved, resulting quickly in bearing failure-or worse."

".......Ford cast an entirely new FE casting called the Side Oiler block early in 1965 where the mains receive a wealth of oil pressure thanks to oil galleries which fed the mains from the sides of the block "

Only mentioning what the author states, but the book appears to be a resource.

Previous post:

The CarTech publication " High Performance Ford Engine Parts Interchange " lists 20 Ford numbers from 1963 to 1968 as 427 High Performance including Side Oiler, Industrial and Marine, Chapter 11 page 94, available as a download @ $4.00.

http://www.cartechbooks.com/vstore/s..._ID=2933&DID=6

Excaliber · #9 (**permalink**) 10-28-2008, 10:42 AM

Let me reiterate, the 427, top or side oiler, is in fact a very reliable and strong motor! Side oiler is of course superior.

Gessford Machine offers a service to modify a 427 for cross bolt mains for those that did not come with it. I think the first FE to come with factory cross bolts was the 406.

Question: When were the top oiler blocks discontinued, or were they? Perhaps manufacture of the top oiler continued along with the side oiler until the demise of the FE series?

Don · #10 (**permalink**) 10-28-2008, 11:09 AM

Mentioned in the Car Tech book by George Reid:

" Cross-bolting the main caps began with the 406 block mid year 1962 "

undy · #11 (**permalink**) 10-28-2008, 11:41 AM

I think a few of the early 406s were not crossbolted, eventually leading to them being crossbolted until the 427s came into being. The "aftermarket" installation of the crossbolt systems were/are targeted towards towards the 428s and 390s, mostly. To my knowledge the only difference between the side and top oilers was the oiling system, to include block casting variances to allow for the oil galleries. None of the variances included strengthening of the side oiler block over the top oiler though..

Dave