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Discussion Starter #1
I just purchased a used Edelbrock 2171 Performer Intake on ebay. I also snagged a remanufactured Holley Truck Avenger 670CFM carb (90670).

I am working on gathering my parts to build up a 400M that I hope to buy soon. My stock original 351M (with 95,000) is running OK but I need more power......instead of shelling out cash for the 400 crank and 400 pistons I hope to pick up a recently rebuilt 400M soon.

I would like to know what parts I should look for next. I definitely need a Cam......anyone know anything about which Cam to buy?

Thanks,
Ol' Blue

 

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House of Windsor 4ever!
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I dunno...this is a build he's doing, so if the mods say it's okay, let it ride. Two things: 1) anytime you upgrade to a newer and more 'bumpity' cam your cam geometry may change, so it all requires measurements, including degreeing the cam and ensuring the valves and pistons will not hit each other. One mistake (whether the cam maker or yours) will cost you plenty; and 2) the pushrod length needs to be measured for rods that will match what you've installed, to prevent bent pushrods or binding valve springs. I also would recommend a set of "beehive"-type valvesprings with a higher lift cam to hold off spring bind. Now this cam will give a less smooth idle, and the tendency is to open the primary throttle plates to compensate, but that results in putting the plates past the idle transfer slots, giving you an idle tip-in flat spot the accelerator pump can't handle. Instead, look to see if the Avenger has adjustable secondary throttle plates. If it does, you can open them slightly to allow more idle air in and smooth out the shaky idle. Adjust idle mixture as needed.
 

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Discussion Starter #5
I started my first build page in the 78-79 section and the mods moved it here so I get totally confused.

I am also totally confused on all this cam stuff so I am going to take it to a mechanic......Cams cost too much to f*&k it up. Honestly, I know I can figure it out and I buy broncos to do the work but I get very frustrated when shit dont work.

I can buy an intake and carb, but the Cams need too many tools and perfection to mess with, I guess. If there was a clear cut kit to buy that had everything I would buy it and do the work but when you throw in rockers and studs and stalls and compression and duration and degrees....it's a vicious cycle.

Some lie to me and tell me it is easy......please!
 

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Discussion Starter #8
The tires are 37", the ratio is 4.10 and the front and rear have detroit lockers. The transmission is a C6. It will be 85% street and 15% trail.....I wont be driving over 55MPH very often. I am getting a rebuilt C6 also.

According to the previous owner of the 400 engine it was rebuilt 10,000 miles ago. I would like to get a mild cam, lifters, new springs and retainers......throw my intake and carb on and hit the road. Does that sound like enough? Obviously, I will inspect the valvetrain and the timing chain should be fine with the recent rebuild, right? Or will the timing chain need upgraded to a double roller? Pushrods upgraded? The stock rockers should work out fine, right? I don't want to open a can of worms.
 

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Discussion Starter #9
Most articles I see note it as a 400M......it is part of the 335 series. Either way ya'll know what I'm talkin bout.
 

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I'd ease up on the cam a bit. A good dual pattern rv/towing cam really shines in a heavy rig. The dual energy or extreme (Comp) in the 270H grind is a good choice. 284H is off the chain, and you'll hate it.
 

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Discussion Starter #11
Finally some good advise......so the 260 to 270 range would be good? It sounds like 270 degree is the most you can go before affecting the torque converter and power accessories.....

How about this?
CAM AND LIFTERS
http://www.jegs.com/i/Comp+Cams/249/CL12-211-2/10002/-1

With this mild cam should I even mess with the valve train.....springs, retainers???? I would rather not, budgetwise.
 

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Stock valve springs in 351M/400 can't handle over .480-.490 lift, so you definitely want to replace them with the recommended springs with whatever cam you choose. Jeg's sucks for cam selection IMO, here's a link to a very versatile cam:

http://www.summitracing.com/parts/CCA-CL32-241-4/

Before you spend your money, a call to the Comp (Crower, Edelbrock, whomever) tech line would be a good place to start.

If you have a stock timing set (smog retarded 8*) get rid of it and get a straight up (0*) timing set. There's the cheapest HP gain you can do for that motor.
 

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Discussion Starter #15
Thanks 78bronco460 for all of your advise.....now I need to figure out how I am getting this 400 that I am coveting home and get it apart for the installation of this stuff....and to get my 351m out and the 400 in....and get my C6 traded in for a rebuilt one. Wish me luck.....pictures to come as I go and I will use this thread to document the build.
 

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you gotta pull the radiator out to have enough room to put the cam in and out.
 
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