Thread: Question about break-in with big springs.

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Okay, I am very close to starting my engine... it is a 396 with a solid flat-tappet cam, so I'm getting worried about break-in failure. I'm wondering if I should take the inner springs out before I start the engine up? Are the springs big enough to cause a problem?

Here are the spring pressures--- It is a Iskendarian solid camshaft, 240 duration, .530 lift. They are dual springs with an inner damper too.

8005-A TYPE: dual w/damper DIA.: 1.530"
RATE: 400 lbs per inch
INSTALLED HEIGHT: 1.875"
SEAT PRESSURE: 135 lbs
OPEN PRESSURE: 395 lbs
COIL BIND: 1.160"

My best advice is don't do it. Replace those springs with some worn-out stockers (single outer). Been there, done that.

I don't have any worn out stockers, I will try to get some though... would it be ok to just take out the inner springs?

That would be my suggestion, I alway's remove the inner spring. So far no problem's.

Ron

Originally Posted by Ron B.

That would be my suggestion, I alway's remove the inner spring. So far no problem's.

Ron

Ron,nice picture.
Now there is something you don't see every day.
A chimp wearing a pink t-shirt with a semi-automatic pistol.

I'd go find a set of well worn stockers, lots of people having cam break-in problems lately. Why risk it?

Originally Posted by erik erikson

Ron,nice picture.
Now there is something you don't see every day.
A chimp wearing a pink t-shirt with a semi-automatic pistol.

The lighting was off I never wear pink, and that's an old picture I've had my ears pinned back since then, nose job is next.

I would either confirm that by removing the inner spring the rate is very similar to stock or use old ones. I would coat the cam lobes and lifter bottoms with cam break in recommended moly lube and add a couple bottles of GM EOS. I would also make sure the engine oil pump is primed up and ready to go. There's recent stuff in here on oil as well. Seems like the 20W50's are much better for break in than the 5W30's for example.

Kitz

Originally Posted by Ron B.

The lighting was off I never wear pink, and that's an old picture I've had my ears pinned back since then, nose job is next.

Your ears seem rather large.

They do make breakin Rocker arm to breakin the new cam with out change springs.

I have a eng standing by to be started with the inners removed. heads came back from my machine shop that way, inners in a box.

Originally Posted by Racecar100

They do make breakin Rocker arm to breakin the new cam with out change springs.

Yes they do,but not for a BBC.

I'm using HD30 Castrol oil, I bought 2 bottles of GM EOS, I used the supplied moly that came with the cam. I have 3 springs... should I take out both inners and leave just the single outer? or just take out the damper in the middle?

I would take all the inner springs out..prelube the eng ,make sure the carb has gas, and don't keep turning the eng if it dosen't fire right off. spark and fuel can be determined before eng start.