So the last bit of valve lash is the headers leaking at the collector.

Right aroung the welds where 4 become 1 is where it's leaking, now I know why the floor is so hot. I thought the header may be too close or touching but it's that the headers leak.

Now for the dumb question. If I want the new headers to line up with current exhaust I have to buy hooker headers? Will they match up at all?

The current headers were hooker small block, previous owner cut & welded to fit instead of waiting for the right headers. Now, I guess I don't even know if the right 351 headers would fit to the exhaust, I am only assuming.

Anyone play enough? The small block headers were cut to fit and I don't know if it's due to the placement of the exhause or if it was due to the small block headers not lining up.

 

Getting the same headers may or may not fit right. Anything different is almost guaranteed to be different. There is simply no standards in headers as there is in factory manifolds. Header manufactures simply come up with a design on the fly to fit - some are tuned, others aren't, and wherever the outlet winds up is where the exhaust needs to be made to fit.

 

If its just a pin holes in the welds you could have the holes welded shut. A exhaust shop would probably do this for 20-30 bucks and you wouldnt have to mess with getting new headers to fit.

 

Sounds line a good thing to do now. The drivers side is pinching on the frame and I would want to fix that.

Good call on the temp fix.

 

Since the headers themselves appear to have been cut and the ends miter-joined to clear the floor, I strongly doubt that anything else will fit up to the rest of your current exhaust without some custom tweaking of the collectors, your pipes, or both.

Welding the hole(s) shut is probably the simplest and probably cheapest way out, even if a piece if sheetmetal needs to be used to cover a larger repair area.

I'd inspect the floor and the top sides of the collectors carefully. From here it isn't clear whether the leaks developed all by themselves, or were the result of poorish welding, or from occasionally rubbing on the floorpan itself. If it's the last one, anything you do by way of repair will be kind of temporary.


Norm

 

The good news is that the collectors/exhaust is not touching the floor pan. the holes are small and I don't know if it's just outside welds or in the middle. They were hot and even knowing it was leaking and was facing towards the engine compartment, it was hard to tell it wasn't valve lash.

I stuffed a towel up between the engine and leak to hear the leak. It's spot on the leak but sounds exactly like lash.

 

ya, header/exhaust leaks sounds exactly like a valve lash problem. Only when you heard them both once you can tell the difference. the exhaust leak has a bit of 'pff-pff-pff-pff' with that, which valvetrain problems don't. especially if the leak is at the head (manifold/jheadergasket) it's hard to determine.

I'm the very same opinion as the others. Take the header out and repair, nothing will fit without cutting/welding. You won't gain anything by buying new I guess

Kalli

 

Yes it looks like someone has used 302/289 headers on a 351 and the taller engine has the headers into the floor boards..Even if there is a hair of clearance when parked what about when the engine torques up under load?..You don't want to wear a hole in your floor!....The proper headers would be much cooler and quieter...All you would have to do is cut off the angled part of the exhaust at the front and reweld on some pieces of straight pipe to mate up to the new headers..

 

Good catch on the taller issue, I didn't think of that and now I see the issue with the drivers side against the frame. Time to hunt for 351 headers.