That’s not the only one I’ve seen that happen to. The compression of the tightened gasket appears to put pressure on the inside wall of the plastic lip and after enough heat cycles it begins to bulge out and crack from the outside in the passage. It happens underneath the crossover too(to be fair, Ford intakes can have this happen here, though it’s not as common due to thicker wall thickness and better material)
The notion that this is user error is pretty humorous, you must work in Apple support :tongue: The only reason I posted that pic of mine was to show there’s a downside to:
IMHO, this was good from several points one of which when installing the intake, there is much less chance of damaging the gasket (although slim, it you got a little rough with it by accident, it could cause an issue)
Less chance of damaging, eh? I have never, ever, had a issue with separate OEM gaskets, the OEM design itself is pretty foolproof, as they clip into the heads. The additional convenience of Dorman’s integral gaskets is outweighed by the failure point they introduce. The issue of installing it wrong somehow to cause the failure on the Dorman(overtightening? Tightening out of sequence perhaps?) still wouldn’t lead to this to happen with OEM. I’ve even pulled OEM intakes from junkyard engines that had signs of overheating where there was no apparent damage to the manifold.
I bought a couple of PI intakes from the junkyard yesterday. They are hard to find. One was off a 2007 Town car and the other a 2007 Crown Vic. I have to wonder though if they are original. No where does it say "FoMoCo"
or have the Ford oval on either one. They do both say Made In USA and have a "W" logo on the upper surface. They also specify the P/N for the gaskets to use imprinted right into the upper runners. Do these sound original or? Is there a difference between these junkyard manifolds and the FPP one? Even on the junkyard ones, it says Made in China on the aluminum crossover piece.
Made in China doesn’t sound right, there should be a Ford part number cast on the bottom of the aluminum crossover between ports. The other tell with Ford intakes VS dorman is there are no holes into the valley between the 2-3 and 6-7 runners, just solid plastic.
The FRPP is identical to the production part though.
Made in China doesn’t sound right, there should be a Ford part number cast on the bottom of the aluminum crossover between ports. The other tell with Ford intakes VS dorman is there are no holes into the valley between the 2-3 and 6-7 runners, just solid plastic.
The FRPP is identical to the production part though.
I looked at several newer Crown Vics at the junkyard. They all had this same manifold and there are holes in between 2-3 and 6-7. The plastic part is Made in the USA but the aluminum part is Made in China. The number on the bottom of the manifold is 615-175 and the number on bottom of the crossover is RN003-05. It appears that Ford is using these manifolds as original equipment on these newer cars. One was a 2007 Lincoln Town car and the other a 2007 Crown Vicky. I bought both manifolds and they are identical as I described with all the same numbers.
I have come to the conclusion that they are both PI Dorman manifolds. Don't know what plastic engine covers are. Those two cars were definitely not from the same owner or fleet. It's strange that both had been replaced. Doesn't say much for the original Ford piece if two random 2007 cars had been changed to Dormans. These manifolds look fine, so I guess I will run them.
I'll have to get the Dorman gaskets though because the Ford ones won't work.
It’s not unusual for a company running those cars for taxi/livery would replace the intakes even if they haven’t failed, just based on their experiences with the OG all plastic ones they would have been operating in the past, it’s better to replace them preventatively than lose fares and an engine on duty. It doesn’t say much about the Dormans either, those may not even be the first ones they installed.
It’s not unusual for a company running those cars for taxi/livery would replace the intakes even if they haven’t failed, just based on their experiences with the OG all plastic ones they would have been operating in the past, it’s better to replace them preventatively than lose fares and an engine on duty. It doesn’t say much about the Dormans either, those may not even be the first ones they installed.
Why would they replace the Ford ones on a 2007? The plastic crossover manifolds were long gone back in 2001. And these cars were from different junkyards and not fleet cars.
Already explained why. How do you know they weren’t fleet cars? The manifold failure isn’t a secret to any company operating these cars for their business, and wouldn’t be out of the ordinary for them to do the same procedures - replace the Ford manifold regardless of whether or not it they’ve gone bad. No surprises. Why did you buy two manifolds from two junkyards?
I can tell you with absolute 100% certainty that Ford never used Dorman intake manifolds on the assembly line.
If he runs a shop, he does this work for the general public. How do you know the customer didn't run it hot. He would have no idea of the history. I have never had a manifold do this. But then again, I have never gotten one this hot. This is obviously heat damage, not just over tightening the bolts. And besides, these manifolds have steel sleeves in the bolt holes to keep excessive stress off the manifold.
I bought two because I have two 97 T Birds. I know the Dormans didn't come with the cars on the assembly line. The two cars were different colors and different makes. Not the same fleet.
The same question can be posed for the OEM failures. The gaskets squash when tightened in order to seal, it’s not a matter of overtightening, when the seal is squeezed onto the manifold, force from the gasket is applied in every direction, the one 1/8” from the port naturally is the one that gives way. Heat is a factor, of course, but there’s nothing to prove it’s from normal 200° heat or 230° overheating. After enough cycles it just tends to weaken. Do the Ford intakes that fail only fail when overheated? I didn’t think so. And Ford’s composite is a damn sight better to the brittle Dorman plastic.
I asked how do you know they weren’t both fleet cars, not whether or not they were part of the same fleet, you answered that several posts ago and I responded to it. If they were both in operation from two different companies, it’s just as probable they’d each have new intake manifolds for the same reasons I already outlined in my two previous posts.
I have never been able to post pictures to forums. I don't have a smart phone, just a 35mm and when I try, they always tell me I have too many pixels to transmit. Anyway believe me or not, I ended up with two Dorman manifolds from random 2007 cars.
The Dorman plastic on the manifolds I bought yesterday are also made in the USA. It's molded right into the runner. Have you had a lab analyze the two materials? Otherwise you are just guessing. I know we like to think of original Ford parts as being better. It's possible that this Ford one is made outside the US. Someone would have to send both manifolds to a materials laboratory to know for sure. No, I am not a Dorman employee but these PI Dormans do look mighty fine. If these manifolds are both off of fleet cars, maybe they know something we don't to go to all the trouble of changing them so early. It doesn't make sense that they would change them just for preventing a future problem since the plastic ones were long gone by 2001.
I like to replace parts once. I'm overall happy with the PI manifold, but the Typhoon appears to be a aluminum version of the PI essentially, with potential for port work to be done. So my question is, is the powerband on the Typhoon essentially the same as that of the PI? If so, I'd rather replace my PI intake with one of those just so I don't have to keep doing it. But, I can buy two and a half PI intakes for what the Typhoon costs, so I'm mildly torn.
Admittedly I’m judging the Dorman by the fact that when compacting the thing for trash pickup the thing shattered like porcelain to my big hammer, while the all plastic broken Ford one needed a couple sawblades to accomplish the same.
If these manifolds are both off of fleet cars, maybe they know something we don't to go to all the trouble of changing them so early. It doesn't make sense that they would change them just for preventing a future problem since the plastic ones were long gone by 2001.
If you were operating a taxi or livery fleet, and bought a few Panthers at an auction, would you just send them all out as is? When you’re running an operation for 30 years and have memories of the Ford plastic intake recall debacle and the lost fares and consequential maintenance, it’s not a risk they’re willing to take and the cost pays for itself in short enough order. Fleets use them because they’re easy to get and quick to service, and reliable enough to get probably 100k miles before they start leaking. Good enough. Not better.
Fleets know better, of course, better than to buy one used. In my anecdotal experience the Dormans tend to stay on the cars until they’re dismantled and crushed, Ford intakes are missing and reused(how do I know? the telltale separate gaskets remaining on the heads). Hmm.
Ford intakes are made either in the US or Canada, I don’t recall which since I don’t have any lying around here anymore. I’m sure someone will chime in and verify.
@Woodman, the Typhoon is a Chinese PI with casting flash in the runners. Portable, yes, worth porting, no. Better options at that price point.
Admittedly I’m judging the Dorman by the fact that when compacting the thing for trash pickup the thing shattered like porcelain to my big hammer, while the all plastic broken Ford one needed a couple sawblades to accomplish the same.
I made it pretty clear I destroyed them both to fit in the trash, because both were trash. Would have been more convenient for me if the Ford one immediately shattered into a dozen conveniently small pieces like the Dorman instead of bouncing across the garage like a basketball when I hit it.
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