headers for 302 and 351W interchangeable?

[cobra427mnsi]

I am pretty sure that the headers for a 302 will fit a 351W and visa versa. I just need confirmation from those in the know.

Paul

[Rick Parker]

They fit the same pattern on the heads however the 351 block is wider and taller making some changes in vertical lengths necessary.

[Double Venom]

Hmm,
Rick you might be right but I was under the standing they were the same, I'll check on that.
DV
(Are you comparing windsors ves. Clevelands?)

[cobra427mnsi]

Originally Posted by Double Venom

Hmm,
Rick you might be right but I was under the standing they were the same, I'll check on that.
DV
(Are you comparing windsors ves. Clevelands?)

Let me rephrase the question. Are the CR small block headers the same for a 302 as for a 351W or did they make different headers? I have headers that I used on a 351W. Will they work for a 302?
When I ordered them from CR, I bought the "small block" headers as opposed to the "big block" headers. I don't think they asked whether I was using them for a 302 or 351W.

DV, no I am not comparing 351windsor vs 351 clevelands. I think they are completely different engines.

Thanks,
Paul

[SuperHart]

Although the header flanges will fit both engines (both engines use the same heads) the headers for the 289/302 will not fit the body in the same way because the 351W is taller and wider than the 289/302. You will need to swap the headers for a pair specifically for the 351W engine. The side pipes, however, will remain the same. If you use the 302 headers, the side pipes will exit the body higher and you will need to modify the cutouts in the body. Also, the side pipes will appear to be too far away from the body if you use the 302 headers. Take Home Point - get the 351W headers or you are asking for major headaches.

[CobraEd]

Just mill the block down to 302 deck height and get shorter rods.


.

[Jimv455]

If your using after market heads watch out for the shape of the port also. They are not all the same..

[tcrist]

I have 302 headers on my 351. The newer CR frame mounts lower the motor about 3/4". I only had to remove the material on the body cutout by about 1/2" to clear the sidepipe. Was not that big of a deal. Pete at CR told me that that they use the same headers for the 302 & the 351 (for what that is worth).
There are pictures in my gallery.
Terry

[Double Venom]

Paul, after hundreds of Cobras built I never had to order a different header. [i] see no problem at all. Talking to Don he only made one size small block headers.

I assume Superhart, couple of posts up, is talking about an entirely different Cobra and as far as I can tell he has never worked on a CR. ? SH- I apologize if I am wrong, but CR's are a totally different breed.

DV

[tcrist]

DV,
My headers (CR LTD) are actually stamped 302L & 302R on the header flange. To get the side pipes to line up if you are replacing a 302 with a 351 you should use different headers because of the deck hieght. CRII gets/got around it by selling different frame mount brackets that lower the 351 by around 3/4". This is according to Pete when I ordered the motor thru CR. I still had to remove material from the sidepipe cutout in the body to clear the sidepipe.
So what I see, in an older CR (as mine is a CR LTD) with the old type frame mount brackets, if you were replacing a 302 with a 351 and using the same headers, you would have to change to the new style motor mounts and brackets or your sidepipes will not clear the body.
In my case I changed to the new style brackets and still needed to modify the body anyway.
This really all depends on how much clearance was cut into the body in the first place.

Terry

[SuperHart]

Well, Double, you guessed correctly. I have never worked on a CR. Mea Culpa for assuming CRs were similar to most other Cobra replicas. I guess removing 1/2" of body material to allow the headers to fit ain't that bad. I wonder, though, how ground clearance for the oil pan and scatter shield is affected if CR lowered the 351 installed height by 3/4".

[tcrist]

Superhart,
My oil pan sets about 3 1/2" from the ground and the frame in the front under the nose has 4".
Terry

[Double Venom]

OK,
To clear up all the techinical questions that have risen, and right fully so, the CR's small block headers ARE the SAME, whether 302 or a 351. On 351's all that is needed is to cut a 1/4 to 3/4's inch higher on the body for the opening, They WILL fit the same and still mount in the same place on the rear of the frame.

Heads: Yes you have to be carefull on special heads as the opening may be "oval" or "square" ports not matching the headers that are used. Nothing that I have seen can not be modified at the headers to fit though.

Yes, different motor mounts have been used since the original ones. Simply because the original ones have gone by the way side but do not have any adverse effect.

Bottom line: CR's small block headers are the same, actually coming from the sme jig!

DV

[cobra427mnsi]

DV

Thanks for the info. You can always be counted on to get the correct information. Your experience building CR is an invaluable asset to us CR owners.

Thanks again

Paul

[Don]

I checked the extra set of headers purchased from Don Scott a few years ago. Stamped on the middle of the flange that bolts to the head is 351L & 351R. When ordering, I had specified the headers were for a 351W. Don had built both the CR I and the engine with Ford GT 40 heads. Do not know if this influenced the stamping identification.

Just mentioning what is stamped on the headers, DV's reply is the expert's answer.