340/360 Exhaust Manifold On A 318?

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Johnny Dart

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Anybody running a 340/360 exhaust manifold on a 318 ?
Any issues I should be aware of ?
If I went this route do I use a 340 or 360 exhaust gasket ?

I might go this route.I like the reliability of the exhaust manifold,plus I wont have to change any of the auto shift linkage.Then down the road when I get a 340 or 360 motor I would be ready to go.

Make sense?

Any insight would be appreciated.

Thanks
John
 
not trying to highjack this thread but how about "302" casting heads? any difference there that the 340 or 360 manifolds wont work?
 
I have 340 exhaust manifolds on a 1970 318, I used 340 gaskets, no problems!!
 
Sedan,


Did you notice any perf gains from the 340 manifolds?
 
Yes I did, I also went with 2 1/4 dual exhaust, x-pipe, and flow master style mufflers, at the end I have chrome a-body exhaust tips. I used a 69 340 driverside manifold and a 71 340 pass manifold. Shortly after that I put on a 68 340 intake, 625 cfm carter carb, mopar performance electronic ignition. I also installed a 323 sure grip in the 8 3/4 rear. All this together really woke up that stock 318! All this was done on a 1970 Dart Swinger. Next I have a camshaft slightly larger than a stock 340 grind I would'nt mind trying out, also a comp cams timing chain and gears.
 
Sedan,
We are working on the same car 70 Dart Swinger.
So far I have added a Ede Performer,Ede 600.

Just got a 2 1/2" mandrel bent dual exhaust kit(made by heartthrob) from Summit.Dam pipes look big.Hope I didnt go to big. :-k

Picture 281.jpg
 
I had 2 1/2" pipes with turbo mufflers that dumped just ahead of the rear axle on my 273. The way that thing throbbed at idle was great. Sounded like a big block, it was almost scary. It would rattle the rear view mirrors on cars next to it at traffic lights. I remember sitting at a light next to a couple of cops one time. They were looking, but they didn't say anything. :)
 
I have 340 exhaust manifolds on a 1970 318, I used 340 gaskets, no problems!!
I am doing this swap on a customer car now (1970 318), seems the gaskets(340) are so big at bottom on center port they won't be able to seal. Did you use a certain # ?
If I lay gasket(felpro) on head flat the port opening of the gasket is right on very bottom end of 318 port. Worried about no seal surface.
 
I found this Mr.Gasket #358 in my pile that fits better but not sure how well a header gasket will hold up.
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I had 2 1/2" pipes with turbo mufflers that dumped just ahead of the rear axle on my 273. The way that thing throbbed at idle was great. Sounded like a big block, it was almost scary. It would rattle the rear view mirrors on cars next to it at traffic lights. I remember sitting at a light next to a couple of cops one time. They were looking, but they didn't say anything. :)
Probably not any louder than some of those boom box cars (the electronic ones that is).
 
Anybody running a 340/360 exhaust manifold on a 318 ?
Any issues I should be aware of ?
If I went this route do I use a 340 or 360 exhaust gasket ?

I might go this route.I like the reliability of the exhaust manifold,plus I wont have to change any of the auto shift linkage.Then down the road when I get a 340 or 360 motor I would be ready to go.

Make sense?

Any insight would be appreciated.

Thanks
John
I used 340 manifolds on a 273S in a early a body without power steering. I had to weld the bottom off the 340 manifolds to match the head ports. It depends on the head ports, so check them.
 
The gaskets you have include a provision for smog ports - look for set of nice thick 340 header gaskets like those shown in a later post
 
I ran TTIs and Dual full-length 3s on my winter motor; a 318. It loved it, 5 winters in a row.It was my transmission test mule: 904/999/A833/A833od/ A833od with GVOD, and splitting gears. Plus 2.76s to 4.30s. Great test engine, with stock heads and cam, plus a small-port spreadbore intake with a TQ. I miss her just thinking about it. Favorite trans? odBox and GVOD
Why?
Stuff her into waaaay too high a gear and floor it; 17 seconds of TQ moan.
Plus; hump her thru the gears splitting as you go, with 4.30s.
Plus; Double overdrive and 65=1250rpm with 2.76s
Second favorite?
A999 with a 2800 and manual shifting.
Why?
Stuff her into waaaay too high a gear and floor it; 17 seconds of TQ moan...........
Least favorite induction?
old Holley TBI on an Excellerator singleplain.
Favorite starter gear;13.29 (3.09x4.30), with a 4-speed. Why? tiresmoke of course.
Favorite with an automatic? 7.48 (2.73x2.74). Why? 17 seconds of TQ moan.......
But I'm turning into a post-hog, so; TTYL

PS; lol, I've run the 340HO manifolds on a couple of other combos, with the same test engine; she always liked 'em with the TQ, and duals. I ran the same TQ topped engine thru teener logs,a Y-pipe and single exhaust, and the only difference from stock that I could tell, was
21 seconds of TQ moan.
I put 340 X-heads on her one time with a 340 cam, 318 logs and single exhaust. The only difference I could tell from the 21 seconds of TQ moan , was the now total lack of acceleration up till about 3500rpm/40mph with 2.73s, what a pig-combo that was. That's when I got the 2800. And 4.10s quickly following.Nope, never got headers or duals for that combo.
 
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