I have searched post first, but wanted to make sure before I purchase them. So here is my idea, I am looking at getting a ZZ4 cam (cheapest roller cam I can find) to put in my carbed 350, and will be using 083 L98 heads. I know I should install screw in studs, but have been looking for a budget valve spring.

So the question is, can I use the ZZ4/LT4 valve springs and retainers that are being sold at performance GM dealers? I was told the stock diameter springs are 1.25 and the ZZ4 valve spring diameter is 1.32. Are the valve spring pockets large enough to do this?

Also, is it a bad idea to use stock roller lifters with this cam, or is it a pretty safe cam swap?

Thanks as always

 

i wouldn't run springs from gm parts. shouldn't be a problem with oem type lifters, the zz4 is a oem type roller right and not billet aftermarket style.

 

the spring pockets will need to be enlarged. had to do it on my L98 heads to fit the springs. i bought my springs, locks, and retainers from a GM dealership. no problems out of them. here's pics of the heads. http://www.fl-thirdgen.org/mrr23/mrr23-3.html you can use the stock lifters. just take them apart and clean them. honestly i spent enough money on the stock iron heads where i should've just gotten some L98 aluminum heads (or ZZ4). i have a line on some ZZ4 heads now for $500. 7000 miles on them.

 

Bummer, I was hopeing they were drop-in springs. So to make these heads to work good with, the zz4 cam, I would need to have the seats cut for larger springs, screw in studs installed, and port them! That sounds like alot.

I am buying the heads for $100
to machine the springs pockets would be about $50?
The zz4 valve springs are $50
To put in screw studs would be $150
Porting kit $50
and then to take about 20hrs to port them

man, I wish I had more money to dish out to just skip this bs and just get a set of dart iron eagles.

bill (sucks to be poor):lala:

 

Screwed studs should not be that expensive if the head is already set up in the mill to machine the spring pockets. A little angle change and the stud bosses can be cut in one plunge with an end mill. The only thing getting "screwed" here is you. If you pull the studs yourself, then drill to a full 3/8" and tap the holes yourself, all the machinist has to do is cut the stud bosses. Ask again, and see if they can "recalculate" the price. Maybe Jethro carried an extra naught or two when cipherin' it up...

 

I had not asked them about the spring pockets, because at first I was going to run a flat tappet cam and bought some valve springs good to .550 lift in the 1.25 diameter, but they are not recomended for roller cams.

And the machine shop said 8.00 to machine each stud boss if I supplied the studs.

So I am new to this, so how do you pull the studs? Do I just attach a nut and just attach a set of vise grips on and pull? I dont have any special tools that I can think of that will pull them. I should have some drill bits that are strong enough to drill them out, and planned on buying a tap and die set anyways.

thanks as always

 

They dropped into the as-delivered pockets of my World S/R Torquer 305's. Revs to 6300 with no float.

I picked those springs when I was planning on using a ZZ4 cam. That plan went by the wayside when my roller block turned out to have cracks in the lifter valley. I picked the cam I'm using now because it was the closest in specs to the ZZ4 in a flat-tappet, computer-compatible design.

An alternative to screw-in studs is to pin them. Drill a hole from the side through the casting and into the stud, drive a roll pin in to retain them. But, screw-ins are probably better. To remove the press-in studs, stack flat washers up to the mid-point or so of the threads, put on a non-locking nut and wrench the studs out by tightening the nut against the washers.