Yep, I agree. You don't need any more than this^ for a hydraulic cam like the 268H. The aluminum heads seem a bit like overkill but at the price you paid they are head and shoulders above any factory iron head you could have had modified, and likely cheaper too. The spec sheet calls for the Fel-Pro 1004 head gasket and you will be giving up a bit of compression compared to the thinner head gasket mentioned in the Super Chevy build up but I would stick to the head manufacturers recommendation. Also, you should be fine with .100 longer pushrods, it won't hurt to check, but the heads and block haven't been surfaced so .100 long is perfect for the .100 long valves they use. Read up on camshaft break in, use the correct lube on the cam and lifters and use some on the rocker balls too, and lastly get oil with zinc, also known as ZDDP.
You've got to measure the Pistons depth in the hole before you pick a head gasket. That fel-pro 1004 gasket is 0.041 compressed height. Perfect for a zero decked block ( yep! measure push rods when that happens) but if the Pistons are down 0.018-0.020 then that 0.041 gasket is too thick. Quench distance is very important. Too much distance there will drop compression (least of troubles) at the same time the bigger gap will cause way more harm than too much compression. Doesn't anyone ever wonder why there are a number of different compressed height head gaskets? Doesn't anyone ever wonder why the rebuilder Pistons have the compression height moved and sit 0.045 ish down in the hole? How the hell does that head manufacture know where the Pistons are?
...... - .. Oh yeah, those aluminum heads can not afford to gain even 1 cc of combustion cHAMBer (see what I did there ) the need to gain compression not loose
I hate to see this turn into a thread hi-jack but as I mentioned before my pistons are.115 in the hole. 1970 LT-1 forgings that were 11-1 comp., I cut the domes and an additional .065 off the crown, IIRC my head gaskets are .028 and the deck averaged .020 before cutting the pistons. 34* total advance with a 6-71 and 600 Holleys and I never saw a down side to the poor (non existent) quench. Did I leave something on the table by cutting the pistons? Maybe, but it was the most economical way of getting near an 8.5-1 compression with the heads I had. With the build in question without going to new pistons right away what kind of "proper" quench can be achieved with factory slugs that have the sump in them? OK, run the .015 gaskets but with any gasket I see no benefit either way.
as Fordors says the build in question ..... is EXACTLY where we're at...and i'm trying to stay on track...lol
I don't know, I wasn't there, & It's not my engine, your happy. I can't say much because my name isn't David vizard and neither is yours. Fitting Pistons in the hole 0.115 would make me re check everything
I have a set of Harlind Sharps with about 5000 miles on them and posi locks you can have for $150+ shipping.
And for 10bucks less than from northern, the 60.99 ones i was telling you about, you can get these Elgins 49.99... and like most internet sales places 99.00 will getcha free shipping. http://www.competitionproducts.com/...-3_8-150-Ratio/productinfo/6150/#.WIG1AtQrKt8 And because you DON'T want to spend 300.00 bucks this is an option for this /your build Recap 1) Stock crate motor with a bump up cam. 2) New alu heads with the stock size 1.26 OD springs. 3) You're not intending this to be a R A C E engine but only a cruiser.
The Scorpions were on my short list of rockers. Nicely made, good reviews. The imported ones have gotten better, but they're still a knock-off of something else. They would probably be fine for something driven mostly on the street. Lunati has one similar to the Scorpions for a little less. The link shows what I wound up buying for $259 and they are very nice. I went with a 7/16" stud instead of the 3/8". http://www.lunatipower.com/Product.aspx?id=2677&gid=198
Let me warn you about those heads, the exhaust valve has been moved from stock a few thousandths, no big deal if you use stock stamped rocker and push rod. But, if you use guideplates the guideplate is no longer in a direct line and angles the rocker (it tips or cants it). If you use a good roller rocker and get down low enough to see across the face of it you'll see it isn't sitting flat and true. The engine will run for a few thousand miles and things will go south. The 'fix' is an adjustable guide plate offered by Isky. You have to have that rocker sitting flat and true.
Back in the day we pinned press in studs. We also split, or cut, the non-adjustable guide plates, when and where ,we needed to, and few years later they became offered for sale . In the (OLDEN times) we Double nutted those high lift 30-30 and higher lift cams, on the press in studs to help hold the adjustment/lash setting ( solid lifters ). the poor man's way...lol When you say canted i'm thinking pigeon toed, or the other way where the roller might not be touching completely across the top of the valve tip, would you articulate more on your explanation, for clarity...? or even show us a picture...if you want to or can... thanks oj
No pic available and I'm not good with words. What I have seen from those chinese heads is that they move the exhaust valve so a larger intake valve can be installed. The guide plate has that slot cut for pushrod and is in a precise location to keep the pushrod centered in the cup of the rocker when it is sitting in the stock location. But now it is moved a few thousandths inboard, not much just .002 or 3, the guide plate will still bolt up under the stud because the hole is generous but the slot is located to direct the pushrod into where the stock rocker would be. Remember the lifter is not a straight shot to the rocker, the pushrod runs at a notceable angle up into the cup of the rocker, the guideplate locates the pushrod into the middle of that cup. When the rocker stud is moved the guideplate puts the pushrod into where the rocker used to be and it'll land on the side of the cup. When the pushrod comes up it isn't pushing in the middle anymore it pushes on the side of the cup and puts a sideload on the rollerrocker bearings that are designed to spread the load across the rocker axle. It will last for a while but after a few thousand miles the engine will start running rougher. The Isky guideplate moves the pushrod to center it in the rocker cup, the rocker stud locks it in place but its a good idea to tackweld them together - you'll see what I mean if you have a look at how they are made.
......saving a space.....will try to MAKE sample PICTURES Edit: I get it... .002-.003 and the roller has (most are) .386" of AREA to touch the valve stem that is only .341" ....
I got a set of Crane aluminum roller rockers that I have been running since late '97. They are just 1.5s. I like them real well. If you want to buy one set of rockers for the rest of your life than like @seb fontana has suggested Harlan Sharps are the way to go. I got a friend that races a BBC, it is stout enough that he unloads the valves between rounds. He has a set of Harlan Sharps that he bought back in the '60s. he finally had one fulcrum go bad in about '90, sent the rocker to be rebuilt and they just sent him a new set no charge.
Another tidbit of info. When running posi-locks. Before anyone pisses on them for them coming loose, you are suppose to have the rocker studs spotfaced before using so the setscrew has a flat place to seat.
Close but not quite. Look at the axis the roller tip runs on, it is parallel to the tip of the valve stem. You could say the axis runs from 9 to 3 o'clock, right? What I've seen those heads do is push on the side of the cup and the tip which cants the rocker to run at an angle from 9:15 to 3:15 so the roller axle is not running parallel to the top of the valve stem, it will be higher on the left than the right.
Yes, thats the idea. It won't get to that extreme angle, you'll be taking stuff apart trying to figure out why it isn't running right. Things will get loose on the axle of the rocker itself (where the needle bearings are there'll develop slop) so the first few thousandths of cam lift will be just taking up slack, no valve movement, and the motor just won't run right. Of course, theres lots of people thta will just keep driving and they're the ones you hear about busting rockers etc and blame all sorts of things 'junk assed chinese rockers' come to mind.
I agree with the Harland Sharp guys. Used to turn the old Gasser 8200 rpm every pass and ran it for 3 years running probably 35-40 events a year. Sold the motor and they were on it ,so don't know how long they ran. The rockers were used when I got them. .060 over 350 ,AFR 220 heads .630 Crane roller. Car ran 9.80s
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