Hey..

I am going to be installing a Crane PowerMax 2032 hyd. roller camshaft into my 87 IROC.

Valve lift for the cam with my 1.6 RR's is as follows.

0.482 on the intake
0.496 on the exhaust

The engine is a completely rebuilt 1987 350 roller block which was punched out 40 over.

The heads are the 083 L98 heads which has been ported out as far they will go. There is a set of 1.6 Roller rockers installed.

Two questions

1. Can I use a set of K-Motion K-700 springs with this cam/rockers/head without worrying about me busting a spring or worse dropping a valve? I have been trying to find the specs on these springs and what the maximum lift they can handle, no real results, think they can handle up to 0.500 lift. Does anyone have any other suggestions for springs? Good real life feedback is what I am looking for... I know I can go and spend $100's of dollars on springs but I am on a budget and if I don't "really" need to spend $300 on springs then I won't, I am sure a lot of you have been in the same situation.

2. Will I need to machine the valve guides?...will the push rods be ok or will they rub?


Any help on this would really help before I make the purchase.

 

"K-Motion" and "without busting a spring" don't belong in the same sentence. Those are GARBAGE.

Use the springs that Crane recommends; or the equivalent from a top-line cam mfr such as Comp, Lunati, Crower, etc., or Manley. Don't mess around with "budget" (cheeeep) stuff. Life is too short to spend it cleaning up after failed cheeeep parts. If you can't afford to do it right ONCE, you sure can't afford to do it cheeeep once, and THEN do it right besides. They're not $300, regardless.

With 1.6 rockers, you probably will have to cut the guides down; or, use .050" offset keepers, and shim the springs up more to get the "spec" installed height.

Impossible to predict about the push rods. In my personal experience, they rub about half the time with 1.6 rockers; sometimes one head on a motor will fit, and the other won't. You just gotta put em together and see. Or, just do the work up front, and be confident that it's OK.

 

Thanks for the reply..... I was talking to Crane and told them my setup. The tech guy I spoke to told me this...

"Go with the Crane Valve Spring kit, P/N 11309-1... it contains the 99915 retainers, the 99846 valve springs, and the 99095 locks. When you get the kit remove the damper internal springs from the 99846 springs so it will work with properly without any interference. The 99846 springs are the same as the 99845 springs without the dampener's"

Does that sound right?

Anybody here running this Crane cam (2032)/springs/rockers in their L98 heads? Any issues?

 

Check your retainer-to-guide clearance, including the stem seal if you use over-the-guide type. You should have .556" travel minimum to provide .060" clearance with your .496" lift.

I'm not sure why he's saying to remove the dampers. Sounds a bit strange to me, but. . .

 

On some heads (Vortecs are a particularly good example) the damper will not fit down over the valve guide, and so a spring with a damper cannot be used. On some heads, especially with the stock seals, the damper will interfere with the seal even though it clears the guide.

Most likely the reason he told you that was because he thinks that you may have that situation, but it's cheaper to buy the "kit" and throw away the dampers, than to buy the springs without dampers and the other components separately.

That spring (99846) is their standard 1.25" diameter spring. It's the one I would expect them to spec for your setup. It's roughly equivalent to the Comp 981 for example.

 

99846s have the dampener, 99845s do not.

And don't confuse how much lift the spring will handle with how much lift the heads will handle. Even if the springs can handle the lift just fine, there is still the other limiting factor- how much retainer-to-guide (or guide seal) clearance you have. Most factory heads the retainer will contact the guide/seal at about .470" lift. Changing springs won't affect this limitation.

 

Yeah... that is how he explained it to me. I told them I had the GM 083 L98 heads and I think he mentioned about the seals. He also said that these springs will hold a lift of up to .575 - .585 lift... so that is a good amount of headroom for me.

I was wondering if I should go the "kit" route or just buy the springs.

My local speed shop can get me the kit for $310 Canadian and just the springs for $240.00 Can.

Will my stock retainers and locks work?

 

Well that is a good thing to know... so that leads me to other questions.

1. Is there anybody on this board running the Crane 2032 with 1.6RR's on stock 083 L98 heads??? If so did you run into any problems?

2. If there will be problems how will I solve them? How can I get around the guide/seal from hitting the retainers?

 

No.

Lots of people have run that cam with 1.6s on about all the motors in these cars. It's one of the more popular ones. With the proper prep work, which is really just the springs retainers & keepers, they've mostly liked it.

You may well find that the Crane retainer is not as tall underneath around the keepers as a stock one; and so gives more clearance to the guide.

Check your retainer-to-guide clearance. If you don't have enough, use .050" offset keepers, and add .050" of shim under the springs to keep the installed height right.

 

Newb questions (I haven't done any valve train work yet)

How do you check the retainer to guide clearance? How much clearance is required?

What is the proper installed height? And how do you check it?

If I install shims will that increase the pressure on the spring?

Will my stock pushrods be OK?

 

With the spring off of the valve, and the seal, retainer, and keepers installed, measure the height between the head and the retainer on the spring mounting surfaces. Now push the valve down until the retainer contacts the guide, and measure again. Subtract the 2nd measurement from the first, and you have the valve travel. Subtract .060" from that, and that's how much lift you can tolerate. Or, measure the travel with a dial indicator, if you have one available.

Installed height is determined by the spring manufacturer. Measurement #1 above is the installed height. Add shims if it is too much.

You install shims to get the proper installed height so you have the proper spring "pressure" (it's actually force, but it's gotten to be called spring pressure, somehow or another).

Your stock pushrods will most likely be okay if they are in good condition.