Che70velle

0HP RESEARCH

The holidays, PRI show, and customer orders have swamped us down a bit so I haven't had a lot of time to come back and update these threads....sorry for the delay....now back to the build.





Camshaft and Timing Set





527 Street





RHS blocks come with their own rear cover and gasket kit which must be used. Front covers are available in std post and long post style so you can run either style oil pump, or aftermarket dry sump (short post). Since all RHS blocks use a raised cam location, this means you have to use the correct timing set and chain length as well. Comp makes a number of these in 2 pole and 4 pole gears depending on your application.






RHS front and rear covers with Comp Cam dual roller timing set.









Custom ground cam to our specs by CompCams



As you can probably tell by the picture, this is using a rather large cam, and rightfully so. Now that we have larger heads, and a much larger engine we can more than make use of a larger cam. For our street setup it will be in the mid 260 duration with a little over 0.750 lift at the valve. This engine is also retaining the OE 55mm size cam bearing size as well.









RHS cam retainer plate






Timing set installed





Now that the cam retainer plate has been installed and the Comp dual row timing chain has been installed we can go about the std cam degree process and make any adjustments at the lower gear to advance or retard the cam as needed. Nice thing about the RHS is that the block as well as the timing covers are all pre machined for dual row chain clearance, unlike the OE covers that require a bit more attention to fit.











527 Race





For the "race" version of the 527 we are going a bit more radical (and may go further than this in the near future) by using a larger cam core, larger bearing, larger lifters, and belt drive timing set. Given we need a cam with over 1.00" lift at the valve this means the cam base circle needs to grow as well to maintain stiffness in the cam itself. So the next logical step up is going to a 60mm cam for easy of availability as well as cam lobes. *We may go to a 65mm or larger depending on what the dyno shows* For now, Comp again is handing the grinding of the cam with some help of Billy Godbold for lobe design. At this time we are not disclosing exact specs but duration is greater than 285 and lift is over 1.080" before lash and deflection.






Sliding the new cam in

60mm on the left, OE 55mm on the right. you can see how much larger even 5mm is

60mm to the left, OE GM 55mm on the right. Notice the relief cut on the lobes to ensure the lifters to each side do not hit the wrong lobe

With this much lift and this large of a bearing size you can see how close we are lift wise of not going much larger unless a larger core is used.






Rather than try and use a chain, we are going with a Jesel Belt drive to operate the cam. This gives us a bit more adjustment on the fly, and ease of cam change if we want to swap cams without pulling the front of the engine apart. Belt drives also help dampen the noise between the crank and cam so in some ways it can help calm down your valvetrain operation....especially on stiff springs as we are going to use to control higher lift cams. The block does have to be machined for the cover to fit and it will replace the OE cover as well. These are dry sump only applications, no room for a OE style oil pump on the front of the crank with these.






Front cover, lower drive and cam plate installed

Cam gear and belt installed as Erik begins to degree the cam.

Jesel offers a number of adjustments as well as +/- 10 degree's at the cam gear by loosening the 4 nuts and sliding the cam.






While the 527 street is going to use your standard link bar style lifters, the race version runs a Jesel keyway lifter and bushing. Again larger than the OE 0.842 diameter, these increase the lifter body size to 0.937 and give us the ability to use a 0.850 wheel (0.700 stock) to further reduce stress on the cam lobe face.






Bushings installed. Make note since the key is only on one side these must be installed correctly or the lifters will not install properly.

0.937 x 0.850 lifter. On the left you can see the small key that guides the lifter and keeps it from turning in the bore. These are also offset to correct pushrod angles.







both lifters installed with offsets to straighten pushrods to the rocker arms.
















Next up we will be looking at the cylinder heads, valves, and springs!

1stls7

Wow,just wow! All the details you have to do to make this engine is incredible. What kind of numbers are you expecting for this to make Street version or race version?

0HP RESEARCH

Depends on what we do for the intake manifold on the street version, it should be north of 750 whp no matter what goes on it. If it does get the same or similar CID intake then it might see north of 800. The drag setup, its hard to say, but on paper north of 1200 would be nice as similar combo top end packages have made over 1100 on 450-460 cid versions.

Both are NA builds, no power adders.

If we get some time we are planning on doing some dyno testing on at least the drag setup later this summer so we will know for sure!