Checking Intake Manifold

[Felix]

Okay, guys, forgive my ignorance...

I've got two intake manifolds that I can use when I put on my rebuilt carb. They look pretty much the same. What's the best way to check to see if the mating surfaces are warped? Is just using a straight-edge good enough? Should I just get one of them milled? And if so, do you have any recommendations on where to take it?

Thanks

[fjman]

I would think that careful inspection of straigtness should work well enough but I htink a lot of folks would say have it milled (Economy Autoparts machine shop in Merrifield is great). I have also heard that some will use 2 new gaskets instead of just one new one to protect against slight warpage.

[greytandy]

Originally Posted by Felix

I've got two intake manifolds that I can use when I put on my rebuilt carb. They look pretty much the same. What's the best way to check to see if the mating surfaces are warped? Is just using a straight-edge good enough? Should I just get one of them milled? And if so, do you have any recommendations on where to take it?

Thanks

If you take the manifolds and put the corresponding open sides together, do you see a gap? If not, both are either warped in exactly the same way or they're both flat. If there's a noticable gap, one is warped with respect to the other. I'm assuming the surfaces are fairly clean. Does that make sense? I'm just guessing here. It won't guarantee a nice fit to the engine, but if you have agreement between the two manifolds your chances are good of an even fit (I would think).

[colangut]

Originally Posted by fjman

I would think that careful inspection of straigtness should work well enough but I htink a lot of folks would say have it milled (Economy Autoparts machine shop in Merrifield is great). I have also heard that some will use 2 new gaskets instead of just one new one to protect against slight warpage.

Felix: Just take a straight edge to it. There is also a trick where you need to leave the two manifolds loose where they bolt together under the carb and then tighten up to the head and to one another at the same time, sneaking up on the torque not all at once. Don't use a crappy torque wrench either and make sure the bolts you have are not too long. I recently saw a leaking intake on a 2F that was caused by bolts being too long where they bottomed out in hole and left the manifold loose. If the manifolds are tight together when you bolt up to the head, they may be slightly offset from one another. The other option would be double check the alinement of both, tighten together and then bolt to head but I figure just use the head as the guide as it might not be perfectly straight. Works for me...if you don't get what I mean, call me and I'll explain further.

Fjman: Do you mean Fairfax Auto Parts Machine Shop in Merryfield? (Fairfax and Economy are the same). At the intersection of 29 and Cedar?

That place used to be great 20 years ago, now I think they send most of their stuff out to be done and just do basic stuff in house. Last I heard, they send their stuff to Kenson up on Picket road near the Economy/Fairfax Auto head quarters. Kenson is OK but not going to impress anyone who's picky. They did my F motor 15 and it turned out OK, but there were a few issues.

Simon at Tyson's Machine is OUTSTANDING. He just did the motor for my friends Bently and it turned out great. Milling the manifolds correctly is not easy, don't do it unless you have to. I've seen a few get fawked up instead of fixed. As with any machine shop, get a 1st hand referal before you go there. Because James Asti at Land Cruiser Connection/4x4 connection sent all his motors there, Simon is VERY familliar with F/2F. The club used to do a lot of business with him as well.

Bill Mathis of Powerhouse Speed is great but is really hard to deal with if your not a "regular" or a "old school local". He's the best around for specialty hi-po gear and has some great know how. He did Stelite valve Seats and sodium filled valves on my BMW R90/S with a diamond seat cutter, I could not get anyone else to touch it and he only charged me $20 bucks a valve. Unless your building a race motor, he's not a good source. Stick with Simon.

-Stumbaugh



-Stumbaugh

[fjman]

Yeah, it was FFX autoparts. I was pretty happy with things but I'm also not an expert. It seemed to be priced out really well and cut me a break when my first used head proved to have a crack in it. I believe they did it there (the rebuild atleast and hottanking)