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Old 12-15-2006, 04:16 PM
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Default Which rockers

Im currently using 1.7 YT's, which some people seem to think arent too hot. Generally I only rev to about 6500rpm, although have taken it to 7000rpm with no apparent problems. It seems to peak around 6300rpm

Cam is 224/230 on 115, 0.581"/0.591", but I wouldnt have any concerns about upping that to 0.610 or so via 1.75 rockers.
CNC'd Edelbrock 215cc heads as supplied by WestCoast Racing heads. My pistons have cutouts in them.

I cannot lift the valve covers, as my coils will foul my brake booster, so basically stock covers must be retained.

I'd also prefer non-adjustable for ease of fitment.

The Jesel SS series look nice, but I think they require substantial clearance mods ?

Could I find a 1.75 ratio rocker that will fit ? Or should I stick with 1.7...

Crane ? Comp camps ? Harland Sharp ??

Im already using Trickflow pushrods.

Any advice is appreciated.
Old 12-15-2006, 05:46 PM
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CRANE CAMS #144750A-16 gets my vote. there lightweight alum. body rocker with there quick lift geometery is an awsome feature. they are a variable ratio rocker, it will make the cam act bigger than it really is advertised. They are pricey, but diffently a killer rocker arm, besides going to there shaft set up. on average they make atleast 17rwhp, and 15rwtq. i srongly recommend double springs with these rockers though. have used them on three 4 different peoples engines and are very pleased with results. as far as what ratio to go with? the 1.7's would be great, but if you want to do the 1.8's your lift would be in the .613/.624 range.
Old 12-15-2006, 05:58 PM
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0.624 sounds like a lot....Im currently on stock lifters. Springs are duals....no idea what brand. I believe they are good for 0.650", although I dont feel the need to go that aggressive.

I'd just like that extra bit of lift to take me over 600

I see Crane offer this in kit form, or as a set of 16 rockers/studs etc

Can I just buy the latter ?? At least, I dont need pushrods ?? ( Im on 7.4" )

Last edited by stevieturbo; 12-15-2006 at 06:07 PM.
Old 12-15-2006, 06:20 PM
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your pushrods won't work, they are to long. the crane kit has been designed to be used with a certain length pushrod. it is much shorter than stock. you can buy everything seperately, but it's just easier to get the kit, and sell your stuff off used.
Old 12-15-2006, 06:40 PM
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Why not just save money and go with the Harland Sharp rebuild on the stock rockers?
Old 12-15-2006, 06:50 PM
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Originally Posted by 99blancoSS
Why not just save money and go with the Harland Sharp rebuild on the stock rockers?
I dont have any stock rockers.
Old 12-15-2006, 06:57 PM
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bummer, keep a look on ebay. You can sometimes snag them for real cheap money on there. Get them for $50 deliverd and you'll still be around $300 total. Which is about half of your other choices
Old 12-15-2006, 07:54 PM
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I am running the Cranes as well, great rockers. I have run both the 1.8's and the 1.7's. The adjustability gives you much better control of the wipe pattern on the valve stem as well.
Old 12-17-2006, 05:58 AM
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Any comments on the Comp Cams pro-magnum 1.75 rockers, compared to the Crane 1.7 Gold. obviously the Comp Cams are a lot cheaper. ALso not sure how the cranes quick lift will affect overlap.... It might introduce a lot more than conventional rockers, which may be a bad thing, or may not.

Or is the 0.624" lift I'd hit with regular 1.8's nothing to be concerned about ?

Do 1.8's have valve more valve cover clearance issues ?

Last edited by stevieturbo; 12-17-2006 at 06:29 AM.
Old 12-17-2006, 08:49 AM
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Either of the Crane rockers fit under the centerbolt valve covers. The 1.7's will still give you the faster valve acceleration off of the seat, just slightly less lift and apparent duration.
Old 12-23-2006, 10:20 AM
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Will these rockers fit under stock valve covers ??

http://www.sdpc2000.com/catalog/3082...ocker-Arms.htm
Old 12-23-2006, 10:36 AM
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I'm not sure, but when I looked into the Jesels before I bought the Cranes I found that the pushrod holes needed to be elongated and there were a couple of other things too. Guess all I am saying is do some research on them before you pull the trigger. They are good rockers though.

Also, I think the Crane's are 1.72 fully open.
Old 12-23-2006, 11:28 AM
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The trigger is itchin !!!!!

I do want to be sure what I buy is right for me.

I wonder which would actually offer more useable lift....regular 1.75's or the crane 1.7's

By that I mean, which would hold the valve open more, for the longest time for more air to actually enter the cylinder to make best use of the heads airflow ?

The cranes are starting to get tempting...
Old 12-23-2006, 01:44 PM
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Originally Posted by stevieturbo

I wonder which would actually offer more useable lift....regular 1.75's or the crane 1.7's

By that I mean, which would hold the valve open more, for the longest time for more air to actually enter the cylinder to make best use of the heads airflow ?

The cranes are starting to get tempting...
I would say the Cranes, since they come off the seat at 1.79 and then settle to 1.72 (I think its 1.72) at about 0.300 lift. Your duration at each lift point will increase compared to the stock rockers that come off the seat at 1.54 and achieve 1.69 at open.
Old 12-23-2006, 01:56 PM
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Cranes nose heavy rockers are a ripoff. Why spend $700 when you can get a new Comp XER cam for half that price.
Old 12-23-2006, 02:06 PM
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I don't agree with Cranes being nose heavy, irregardless it is rotary inertia that matters and they are less than stock and much stiffer.

Look at his car, I think he may need to yank the motor to do a cam change.
Old 12-23-2006, 02:28 PM
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i would agree with doing the cranes, have used them on several different motors, and a by far the best rockers out there right now. they are pricey, but you are getting what you are paying for. i don't know of any other rockers who can deliver 20rwhp.
Old 12-23-2006, 02:36 PM
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I can do a cam swap in situ...I just dont want to. Its a PITA

Rockers are easy, and as a few guys seem to think the YT's ( including W2W, so I take it they know ) arent that good....I want to change them anyway.
Old 12-23-2006, 02:39 PM
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I just had My OEM rockers with 80,000 miles rebuilt by Harland Sharpe for $250 for a 408 in the works. Lifetime warranty. All the aftermarket rockers IMO is a bunch of hype.
Old 12-23-2006, 05:18 PM
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Originally Posted by bigdsz
I just had My OEM rockers with 80,000 miles rebuilt by Harland Sharpe for $250 for a 408 in the works. Lifetime warranty. All the aftermarket rockers IMO is a bunch of hype.
Did you happen to check your wipe pattern on the stock rockers. One thing that pushed me to aftermarket was the wipe pattern on the stockers that was all over the place, not only front to back but side to side also. I tried shimming them, and could get the front to back better but the side to side still bothered me especially with the much increased spring pressures we are all running. I spent a week last winter setting up my heads on the bench before installing them.

The added spring pressure and poor wipe pattern can lead to excess wear on the valve guides. Don't get me wrong, the stock rockers are excellent for a factory rocker, but at the same time GM set them up based on tolerance stack-ups so they could be bolted in place and have acceptable guide wear over the life of the motor with the low spring loads they were using. Then we come along, put in honking valve springs and fast ramp cams and all bets are off. I found with the Cranes, due to the adjustability, I could tighten up the wipe pattern to right where it should be and it was consistent between each valve. In my opinion, this is one area a lot of guys overlook when building their motors.



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