[chiphead]

I've got a '69 400 with 62 heads with a bad aftermarket cam. The 62s appear to have the stock upper valvetrain. What's the max lift I need to stay under, with stock length valves and guide heights? I need a low-buck repair until I get the rest of the car sorted. I don't want to pull the heads, but I can change valvesprings and rocker studs. Car already has stall converter and 3.55s.

Unsure of compression ratio, but it pumps 150 PSI with a cam that's very rumpy at 1000 RPM. I'm guessing 9.5-10.1 range. I'm thinking Crower 60243 but don't know if the heads can take .495" lift.

Thanks!

[Matt Meaney]

stock springs, about all you want is .450ish lift.
to ball park what you have now, you could bottom out the lifter and turn the engine over manually, measuring how far the retainer moves. use a tape measure in a pinch.
when you pull out the old cam, maybe the numbers on it will tell what it is and you could go by that.
last resort, use a dial caliper on the base circle and then over the nose. the difference being the lift, than multiply by the rocker ratio.

[25stevem]

Here’s what your dealing with if the head is totally stock.

The uncut valve guide height is about .670”.

With a stock valve and stock retainer that accepts the valve seal O-ring you have .560” before the retainer hits the guide as in my photo here.

The stock valve spring installed height is 1.590” or so, this gives about 110!psi on the seat.

I

If the springs are stock I would not run more then .480” lift.

Note that at even .470” lift if the springs are stockers then there gonna give up pretty fast!

Ask me how I know this.

If your guides are not cut for positive valve seals then you must run the stock retainer with its O-ring and the stock valve spring oil shield.

Note that this shield limits the type/ kind of aftermarket valve spring you can run.

If you do not want to run the shield then you must cut the valve guide tops for positive seals.

[MarkS57]

For my 62's, I used something like this but the Crane version, same idea. Gives you options. But, I'd at least go w/ 7/16 studs, ask me how I know.

https://butlerperformance.com/i-2445...tegory:1459605

[chiphead]

Thanks, that's a great tip on those valvesprings.

What do you guys think about the Summit 2802 in this application?

[Jay S]

2802 would be a good choice. If your looking for something cheap, the Crower’s are a lot more money and might not be easy to find.

I have done a few Melling spc-8’s (041’s) with stock spring height and 1.5s. I would do comp 988-16’s instead of Crower 68404’s spring unless you decide you want a more aggressive profile.

If you leave the springs alone I would drop down to the 2801.

[chiphead]

Thanks for the input. I'm going to have to do something, I just confirmed this cam is likely dead. The #8 intake lobe looks suspicious as anything. In addition to that, the upper valvetrain geometry is totally whacked.

It looks like somebody installed a large HFT cam but reused the bottleneck studs, the stock retainers, the spring shields and the drippers. The guides have the white PC seals fitted, but the retainer has been mashing the snot out of them. In addition to that, there are chevy crimp nuts doubled on top of the bottleneck nuts. WTF, over.

At least this head has screw-in studs, so it's easy to replace them. So I need a full recipe for 1.6IH. Studs, retainers, springs, etc. Are there still pro builders on here that can supply parts? Thanks!

[25stevem]

Since you have found proof that whoever stuffed that Cam in did not know what they where doing and likely had the geometry off, first pull the heads and take the valves out so you can check the condition of the guides and valve stems.

You can then have a complete shopping list of what you need seeing as you might find that both heads need all or some new guides and that new valves maybe needed also.
New /needed parts are not hard to get a hold of these days other then certain Cams, and you need to pick a cam in order to know what the other proper parts are needed to go with it.

[Jay S]

Sounds like you need to add valve seals to the list also. They don’t take hits very well.

[Verdoro 68]

Originally Posted by chiphead

The guides have the white PC seals fitted, but the retainer has been mashing the snot out of them.

I had this happen with a 60916, stock-ish #16s and 1.65 rockers. The issue was that the machine shop didn't cut down the new valve guides far enough (or evenly - very sloppy work). Once that was repaired, I ran shorter retainers to add clearance and all was good.

When I tore down the engine earlier this year (8 years later), it was clear that the trash from the seal had done quite a bit of damage to the bearings. There was still a good bit of Viton in the oil pump pickup. Something to keep in mind if you have the opportunity to tear this engine down further.

Mashed seals: https://forums.maxperformanceinc.com...0&postcount=86

Bearing damage: https://forums.maxperformanceinc.com...5&postcount=20

[chiphead]

So I got the cam out tonight. The #7 exhaust lobe was scrubbing the lifter, it was indeed going flat. But I caught it early.

The cam is a Crane HIT-284-2NC from the late 1980s.

Adv. 284 - 292

.050 228 - 236

Lift .490 - .510. w/ 1.5 rockers

LSA 114

So yeah, a little too much lift for the PC seals and factory retainers.
Is this cam still made, or how can I get a copy of it? It ran great and chopped wood at idle. I'd put another one back in! It looks like the closest grind would in fact be the Crower 60243.

Dur @ .050” Lift: 228°/235°
Gross Lift: .479”/.494”
LSA: 112°

Now if I can only get my hands on one!

[25stevem]

Comp cams has Lobes in there Magnum series that are very close.
230@.050” .480” with 1.5
236@.050 .490” with 1.5

You should ring them up and see if they have a core to grind you one up on with the 114 spec.

Actually since it’s one of your exh lobes that is going bad they may be able to regrind your Crane core and you would just have to drop down to a .050” spec of 234 to 232.

How much is number 7 lobe worn when compared to another exh lobe on the cam.

[Jay S]

All cams from crane are special order from Compcams. I run some crane cams, but have not tried to have one duplicated since crane got bought out, you might need to know the right person at comp to make an order. Ken Crocie would know who to talk too, he is the only one I know of that has had a crane cam ground since they got bought out by the conglomerate that owns Compcams.

If you want to get the car going again quickly stick with something off the shelf or a custom grind that has a cam core available. I don’t know what the wait would be to get a custom crane ground by Compcams? Guessing it would be a llloooonnnngggg wait.

[chiphead]

Yeah I need to get this thing rolling. So it looks like Crower's stuff is backordered.

Summit 2802 be the next best thing?

Duration at 050 inch Lift: 224 int./234 exh.
Advertised Intake Duration: 298
Advertised Exhaust Duration: 303
Intake Valve Lift 0.466 in.
Exhaust Valve Lift 0.488 in.
114LSA

What lifters? Hi-lift johnson? Are the camsaver lifters worth the money?

[Jay S]

Best HFT lifter for the price is these hylift J’s at Butler

https://butlerperformance.com/i-3164...tegory:1234799

There is a set of new HYlift Johnson on eBay for $85 that has had the box opened. I noticed them the other day, was tempted to get them. I still may, unless you get them first. Lol

The summit 2802 seems like the natural choice if cheap and available is two big criteria. It will idle slightly smoother and lack a little of the top end of the crane, but it does pretty well. The crane is more aggressive, with more assymetric's in it’s design.

[77 TRASHCAN]

I've been told, here, that the 2802 and 60243, are very close.

[Jay S]

If I am shopping for lifters the Crower cam saver lifters are the next option if I can’t find HLJ’s.

I have done quite a few super lube Rhoad’s lifters, which are modified HLJ’s with the groove similar to Crower cam savers.

[phil400]

Not to hijack but At what rpm would the 2802 nose over in a 400?

[25stevem]

Phil, are you talking about a stock 400 and if so what heck year?

[phil400]

Steve let's say your typical. 030 over 400 large valve D-port heads with 9.5~10 to 1 comp ratio.