I have purchased the Hyper-Pak and shorty headers from Clifford and the surface area where the small butterfly washers hold the manifolds to the head are not flat. I am sure I will not be able to get a good seal at this point. Has anyone been down this road before and have a suggestion?. I have searched the existing articles and find lots of negative comments about Clifford but nothing specifically addressing this situation.

Your are going to have to get a machine shop to machine the mounting flanges thinner but flat.

That's fine, you don't need crazy torque at those nuts. The aluminum will conform to the washer to a certain extent anyways. It's a cast piece, the only areas that will be true are the machined surfaces.

Is this one of their new/recent productions? Take some pictures, would be interested to see how good this casting is. I believe the previous ones had issues with how square the inside of the runners were.

Edit: Just to make things clear - the surface that touches the head needs to be as flat as possible to make good contact with the gasket. The surface touching the actual washer doesn't need to be super flat, just "more or less" even with the headers. You can use a burr, file or your favorite form of metal removal (load it with wax to prevent aluminum build up) to even it out if your that worried.

I have the Clifford intake/headers and believe me it's not a problem.I used the stock triangle washers and they sort of lay over at an angle and WILL touch/tighten/torque both intake an headers.Don't worry about the off angle it's really not that much even with Cliffords gasket.That being said I would highly recommend the REMFLEX gasket as it's uber thick and only needs like 5 ft lbs of torque to seal and hold.I was concerned about the same thing when I first installed my set and even called Clifford about this issue.They recommended modifing regular washers to fit the area and to oval out the hole(in washer) and maybe even 'stepping' the washer,sort of an S bend I guess.In any event I looked at the tight working area, thought about modifing stuff and said screw this and used the stock slant hardware=result,works fine.Might as well use new studs as long as it's exposed and brass nuts too.I can try for a closeup pic if you need.Good luck

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83 B-150 slant 6,4 speed. 79 B-300 360 pathfinder 4x4. 74 W-300 318 4x4 git-r-done 80 B-100 sl6,4speed

OK guys, thanks for the tips. After a full day of grind fit, grind fit, grind fit, I think that I have a descent seal.

Pierre, sorry I forgot about your request for pics until I sat down to make this entry.

Now I hope that somebody can enlighten me on throttle and kickdown linkages.

I appreciate the help.

What carburetor are you going to use?

Kickdown will be easiest with a Lokar or similar cable type.

CJ

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390 Holley

Cable pedal and so forth off a later A-body. Get the Mopar throttle lever adapter from Holley. (Otherwise you won't get WOT.)

Or you could go easy on yourself and install a 500cfm Edelbrock and avoid most of the tuning.

CJ

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Motor is 60 over, .035 off the head, 1.77intake/1.44 exhaust, pocket porting, 270 cam, balanced. I figured the 390 was plenty of carb, have I miscalculated?

No, you calculated just fine.
The Edelbrock won't open the secondary air valve past what the engine wants. It's just a whole bunch easier to set up, and it'll put down remarkably similar times at the strip.

Did you cc the head and compute your compression?


CJ

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53.2cc, did not calculate compression, Machinist stated approx 9.5

If you look at the "Sickness" article and some of my posts about making the "Hpak" streetable, you'll find you *WILL* have to use an angle grinder to hog down the outside runners a bit to accept the triangle washers, they just don't fit without a bit of "notching"...you will also have to take some time to get the thickness of the flanges right, I used to run the defunct Mr.Gasket #320, I now run a Remflex gasket and everything is sealed at the head nicely and stays sealed...

Carb options will depend on your goal:

I currently drive daily on the street with a Holley 390, it turns in good mileage and moderate power (10.3:1 compression, 280/270 Erson, 170/1.44 valves, dutra duals, true dual exhaust). Dragging around a 3400 lb Feather Duster I can pull down the mid 16's on the 390, and get 24 on the highway (3.55 sure grip and A-833OD helps quite a bit). Swapping to a Holley 600 with annular boosters, but restricting it to a "brown" spring dropped me down to a 16.28... at that point, I know the weight of the car, and the rear gears are now limiting me, along with the problem that the cam puts out as much power as a Comp Cam 252 at speeds below 2500 rpm...but the duration and grind likes things up in the Hpak Zone (3500-6000), where the intake likes to ram-tune... so I have a couple of wintertime changes to make before drag season.

I only chose the Holley for tuneability and the fact that my grandfather had left me quite a few cores to play with. I think given the data, the Edelbrock AVS 500cfm with Electric Choke is a good choice, and it may need a tuning kit to dial it in just right, it should in all respects deliver the same mileage and power with much less fuss (empty the bowl and change the jets and power valve...). Remanf'd versions are currently selling at Schucks/Kragens/O'Reilly's for $288, so I think next month I'm going to snag one and either try it on the Hpak, or use it on the offy on the Beater Valiant.

Glean through my old posts, there are some nice trial and error posts I made while getting things dialed in on the "mild" engine, key words "Hpak" by DusterIdiot.

Good Luck, once you complete the engineering feats of installing one fo these and getting it dialed in you'll have made quite a journey, and you will be rewarded by a smile when the slant under your hood grows the 7th cylinder after 3500rpm...



-DusterIdiot

That's a nice distinction DI, The AVS gives you the ability to set when the secondary air valve comes in. The Performer has a weight, so to change it, you have to take it apart and drill holes in it.
Somewhat less elegant.

The Edelbrock or Carter AVS and AFB series are the only carbs I wouldn't worry about coming from a reman house. It's much more difficult to screw a Carter/Edelbrock up sufficiently to make them run poorly!

CJ

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