Hi, I need a little advice. When I dyno'ed my car, the power was falling off at 5700. It has a healthy hydraulic roller cam, and I am running the E-Tec 200 heads. We used the valve springs that came on the E-Tec heads, because the pressures on the Edelbrock springs were very close to what Comp recommended for the cam. When I called Comp about it, he told me the spring pressures were indeed close, but the main benefit is that the Comp springs are duals, with a damper. In order to put the new springs and retainers and such on, my engine builder wants the heads back off the motor, and in his shop. If at all possible, I'd rather not pull the heads, and I started to consider the AFR Hydra Rev. Seeing as the springs on the heads already are close in pressure, is it possible that the Hydra Rev could do the trick until maybe the winter of 03? At that time I'm sure I'll have the motor back out, but then will a person benefit from the stiffer valve springs and the Hydra Rev? Its a touchy subject, and I really am not ready to tear the heads back off my new motor already. Any thoughts guys?

 

If I were you I'd get the AFR hydra-rev kit

 

Not to sound stupid, but what is the hydra-rev kit, I assume it helps to keep the valves from floating?

 

guess you could run that idea by comps tech again. i'd run the duel springs. i'd say the thing your builder wants to do is machine out the spring seats for larger diameter springs and that's why he wants to pull the heads off.

 

If the heads already have the right size pockets for the springs you want to use, there's no reason to pull them to change the springs. Measure the diameter of the springs that are on there now. If they're the same size as what should be there, then just change them. If they're only 1.25" diameter (stock size), you'll need to pull them and get them machined for real valve springs.

The Hydra-Rev kit is a plate and a set of additional springs that go under the head, and press down on the lifters. It attempts to assist the valve springs by overcoming the inertia from the mass of the lifters. I would not use it except as a last resort. It is totally unnecessary in a properly built motor with a street cam running at less than 7000 RPM. Get the right valve springs.

 

The heads already have the 1.45 pocket, and comp has a spring that is 1.45 that is perfect, but my engine builder wants to disassemble the heads and work with the installed heights, etc. etc. Another concern is the clearance between the roller rocker and the retainer. If the Comp retainers are physically any bigger than the Edelbrock ones, we'll have problems too, because he already had to take the fly cutter and take material from the bottom of the rockers. These are the reasons he wants the heads in his hands, and I want them out of mine for the valve spring job. So the Hydra Rev is more or less a band aid?

 

If the retainers are hitting the rocker arm could that be an indication that taller pushrods are needed to correct geometry? And are the installed heights the same on the two different springs? If so there shouldn't be too much work to do.

Just throwing some stuff out there cause I know how much more painful it is to pull the heads than just the vavle covers. I swapped out springs this weekend with the heads installed and it was not to bad at all. I used the attachment for my compression tester(removed the little shrader thingy inside) and plugged it into my air compressor to pressurize the cylinders. A spring compressor that works with the heads in the car only cost me 20 bucks.

 

Actually, the retainer clearance problem is a whole other war. My engine builder went round after round with Edelbrock saying that there is a problem with the heads. The people at Edelbrock were not helpful at all, and were even being a bit obnxious about the problem. He told them that the geometry was right on, and that he was using the EXACT Crane Gold rockers they recommend. He also told them it would take a .300 longer pushrod to solve the clearance problem, and that the roller would be off the tip of the valve at that pont. The best they could come up with was that it needed a longer pushrod. I called Edelbrock one day to ask about it and I got a very helpful person. All he was concerned about were the casting numbers on the heads. He didnt come out and say anything about faulty products or anything, but he was very concerned about what the casting numbers on the heads were. Kinda makes you wonder.......
My engine builder knew that notching rockers is by no means recommended, but at the point where the heads and everything are bolted on, there isnt awhole lot of other options. If they had said something to him about possible casting problems, it may have been a different story.