How to tell 351W exhaust manifolds from 302?

Hi guys.

My turn to pick your brains.

As the title says I´d like to know how I can tell if stock exhaust manifolds are really 351W ones. I know the encoded data tells the year and the car that the part was originally designed for and the number tells me what department of the firm the part was made by ( engine, interior etc).

But is there anything that identifies the part as such? A code or anything that says "Manifold for a 351W"?

The story behind it is that I can get manifolds from a 1970 Ford LTD. The owner thinks it has the original manifolds but we all know that those might have been replaced in the past. Now, I have my old 302 ones here (one is dated "D4", so much for "original"!), so I don´t wanna risk buying the same ones......

Thanks!

This may help. http://mustangtek.com/exhaust/Exhaust.html Chuck

Even if it is a 351W manifold from a LTD it may not fit because it is from a different chassis. I'll see if I can find some more information.

Mike,

I would suggest that the easiest way to tell the difference is to measure the ports. The 302 size will be 1.82" X .90" while the 351W will be 1.82" X 1.02".

If you know it is a small block intake and the width of the port is less than 1", it is probably for a 289/302. If the width is a little over an inch, you probably have a 351W.

Hope this helps.

BT

Hey Mike,

Got this info from Fordication:

Windsor engine characteristics


Thermostat housing bolted to the front of the intake manifold

 


All 289/302/351's have intake bolts 90 degrees to the ground

 


289/302/351's have evenly spaced exhausts aimed 90 degrees from length of head

 


5/8" (18mm) spark plugs

 


The 351W and 302 are very different:

 


The 351W has a taller deck height than the 302. (a 302 will have the intake almost flush with the base of the distributor... where it goes into the block..... a 351w will have about 1/2 inch lip there where the intake meets the block.)

 


Since the deck height is taller the intake manifold is wider on the 351w than on the 302.

 


The 351W uses a larger main journal than the 302. there are 2 physical ways of telling a 302 vs. a 351w. Also, in between the frost plugs on a 351W there will be what appears to be a triangle or diamond (the way I was told) indented cast into the block...a 302 doesn't have those.

 


a 351W is wider between the heads compared to a 302 (the intake manifold is wider by about 1-1/2") and 351 pistons have a different pin height. You can use 302 pistons in a 351 if you stroke it to a 393

 


quick ID tip: The lower thermostat housing bolt on the 302 will be below the top of the water pump and you won't be able to put a socket on it. On the 351W you can remove the bolt with a socket.

 




 


DJ

BT, I thought he was talking about exhaust manifolds, maybe not.

Luxstang, Why do you want to use stock manifolds on your Ford Racing crate engine? Also, I can not find any info on 70 LTD 351W manifold casting numbers. If someone has a master parts list they may be able to help.

Chuck

BT, I thought he was talking about exhaust manifolds, maybe not.

Luxstang, Why do you want to use stock manifolds on your Ford Racing crate engine? Also, I can not find any info on 70 LTD 351W manifold casting numbers. If someone has a master parts list they may be able to help.

Chuck

Click to expand...

Duh!!

Reread the original post and as my Daughter would say, "My Bad!" he does say "Exhaust" in his post.

BT

Hi Guys,

thanks for your replies.

However I had to edit the subject and the text in the post.

I really meant exhaust manifolds.

As English is not my native language, I forgot that in fact a manifold could be both intake and exhaust. My bad..:blush:

Sorry!

As for the reason I thought about having stock manifolds on the car: I need the ground clearance. The long tube headers I´ve had on the car for 8 years now end underneath the floorboards and scrape the ground on speedbumps and driveways. I got only barely 2 inches between the headers and the ground. Not good!

Now I got a stock replacement exhaust for a 351 C Mach1 and I got some shorty headers but I thought, while I´m at it, I might as well go back to factory look.

LOL! Now those are interchangeable. For the 1970 302 and 351w this should be the same part numbers: D0OE-9431-D and D0OE-9430-D

Not sure if this helps but I thought I would post it again if anybody needs it.

Ford part numbers.

http://www.fordmustangparts.com/inv1213b.htm

Hi Guys,

thanks for your replies.

However I had to edit the subject and the text in the post.

I really meant exhaust manifolds.

As English is not my native language, I forgot that in fact a manifold could be both intake and exhaust. My bad..:blush:

Sorry!

As for the reason I thought about having stock manifolds on the car: I need the ground clearance. The long tube headers I´ve had on the car for 8 years now end underneath the floorboards and scrape the ground on speedbumps and driveways. I got only barely 2 inches between the headers and the ground. Not good!

Now I got a stock replacement exhaust for a 351 C Mach1 and I got some shorty headers but I thought, while I´m at it, I might as well go back to factory look.

Click to expand...

If the shorty headers solve the clearance problem I'd leave them on. However it is your car. Do what pleases you. Viel Gluck, Chuck

Hi Guys,

thanks for your replies.

However I had to edit the subject and the text in the post.

I really meant exhaust manifolds.

As English is not my native language, I forgot that in fact a manifold could be both intake and exhaust. My bad..:blush:

Sorry!

As for the reason I thought about having stock manifolds on the car: I need the ground clearance. The long tube headers I´ve had on the car for 8 years now end underneath the floorboards and scrape the ground on speedbumps and driveways. I got only barely 2 inches between the headers and the ground. Not good!

Now I got a stock replacement exhaust for a 351 C Mach1 and I got some shorty headers but I thought, while I´m at it, I might as well go back to factory look.

Click to expand...

THANKS for the clarification, Mike as I thought I was REALLY losing it!

That having been said (and I don't mean to insult you), I am not so sure that you will be "happy" with the stock exhaust on that crate motor as it sort of defeats the purpose. Remember, as you increase what is going into that "air pump", the more important it is to make sure there are minimum restrictions on getting it out.

To me, the better idea would be to go with the shorty headers with the crate motor as you won't (or shouldn't) have the problem with ground clearance. After running the long tube headers on your Cleveland, I found it hard to believe the "satisfaction levels" will be there with the stock relatively restrictive exhaust manifolds on the Windsor.

Of course, in the end the decision is yours.

BT

Yeah, I´ll probably end up using the shorties anyway, as I got them here.

But I´, still interested if it is possible to identify the part as being a 351 manifold. Before I got the shorties I was looking for original ones and I found all kinds of information but none that helped.

I had found the page that Chuck posted (thanks!) last year,but again, it only shows the parts but the code on my 302s is exactly the same as the one shown on the website for the 351s......:huh:

Losing the long tube headers might not make that much of a difference, as my engine is build for torque, not for high RPM horse power. So the shorties or even the stock manifolds might even be slight improvement.