Newbee need some advise - AMC401 Build

Hi guys

Kind of newbie here. Bought myself an 1979 CJ7 with an V8 401 engine and a torgueflight 727 auto transmission. We did a frame off restauration (exept the engine and transmission). Drove it this summer, but my Oil pressure is kind of critical when warm. Cold i have 60-70 psi of pressure and warm 0-5 psi at idle and 10-15 psi at 2000 rpm. One day at the Beach under an acceraltion, the engine starts making a ticking noise, so i think one of the lifters maybe gone bad. Allthrough the engine runs and drive good...

Well anyway, i decided to make what some would Call a semi renovation. I dont currently have the space and facility to Pull out the engine, so crank and cam bearings just have to sit tight for now.

The engine has a edelbrock performer intake with a 4bbl edelbrock Carb. The heads are iron and honestly dont know much about the pistons, valvetrain a.s.o. The exhaust Headers are Doug's fenderwell style - ceramic coated.

My plan Was to do an udgrade of the rockers, cam, lifters, timing cover, timing chain, HEI distributor, and all the Oil pump udgrade that bulltear Provides.

So here's my plan for parts..:

COMP Cams High Energy Die-Cast Aluminum Rocker Arms 17044-16
COMP Cams High Energy Rocker Arm Studs 4500-16

Lunati Voodoo Cam and Lifter Kits 10100702LK
Lunati 93018 Timing chain and gear set. AMC 401

Bulltear AMC-V8 Pushrods gold (increased crank oiling) with smaller feedhole
Bulltear HD Guideplates AMC V8 (71-91)

Bulltear Oil filter relocation kit
Bulltear AMC V8 timing cover
Bulltear AMC HEI unit w/o gear set
Bulltear AMC "HRC" oil pump gears

Any comments and ideas are welcome :sa::playingleapfrog::playingleapfrog:

Thanks
Morten Christensen // Denmark

Unless the 401 is 73 or older, you need to do quite a bit of machining to the heads to use individual rockers on the bridged rocker heads. There are roller rockers from Harland-Sharp and Scorpion that will work on the bridged rocker heads without machining or guide plates. They cost more, but you eliminate the cost of machine work and guide plates, so dollar-for-dollar, they're about the same.

I've never used Lunati Cams, but haven't heard anything bad. Be careful with any aftermarket timing set with the alignment of the oiling slot for the dizzy gear.

I prefer the Bulltear cam bearings with the smaller oil holes to the pushrods. They both serve the same function, so either is good.

Before you try anything else, get the HRC gears and a mid-plate. Block the filter bypass (use good quality filters like WIX or Napa Gold w/internal bypass). Make sure the pressure relief valve in the oil filter adapter is clean of varnish and moves freely in it's bore. Make sure the pointed end is away from the spring. (amazing how many I've found in backwards that have led to pressure problems).

If you're doing a full rebuild then the timing cover is a good idea. I'm not a big fan of remote filters. I'm not a big fan of HEI either. I've run a Mallory Unilite on many engines without a single hiccup.

Keep us updated on your build.

Bob
tufcj

//Bob

Thanks for your reply..

Okay i get your roller rockers point,- but can't Seem to find the Right one..? Do you have a link, or part number for let say scorpions rockers?

My current rockers are Stock and they are mounted with a straight bolt to the heads. I guess i'll need some arm studs for the New type of rockers than?

I belive my Oil adapter has the blocking filter bypass plate and from what i can Read almost every Oil filters today has an Internal bypass...correct? I know for a fact my pressure relief valve is mounted correct through ;-)

I decided to go with the msd distributor (non hei) instead and of course also with a New Msd matching cam gear.

Thanks

Morten

Do you have a casting number for the heads? Early heads (73 and older) use a Chevy style individual rocker. With these, you can use a small block Chevy stud, and use the Comp cams rocker you listed, guide plates aren't needed. 74-up heads used a "bridged" rocker, the intake and exhaust rockers are held together with a U shaped bridge. The Harland-Sharp # is S40046A, Scorpion # 3297.

To use an individual rocker on the later bridged head, you need to machine down the pedestal about .250" + the thickness of the guide plate, usually about .375" total. The stud hole needs to be drilled and tapped to 7/16", then you need to buy studs, guide plates and hardened pushrods.

Has this engine ever been rebuilt? I've found that about 50% of the engines I've done (14 total) that have factory cam bearings have cam bearing issues, which quickly causes oil pressure problems. If you pull the cam, be sure to shine a flashlight down the cam bore and look at the cam bearing surfaces. A bore-scope is even better if you can borrow one. The factory coating flakes off and causes huge oil bleed-off.

Bob
tufcj

I'll have to get back to you about the casting number..

I'm not sure about the engine Rebuilt. I bought the jeep from a guy in the netherlands. He bought it from germany and drove it to a lokal jeep buildershop. I have an invoice dated from around 2001, where he paid 10000 euro (approx 11.700$). On the invoice there is just specifyed an engine and type and I guess the total amount is because of Labour, tax a.s.o. He had it for 16 years and drove around 45000 km in it, so again.. Was the engine rebuilt in 2001?? Well i hope to belive so, or else I would say he's been ripped off hard.
I do have a bore scoope, so i'll take a close look then the time is in.

/Morten

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