545" High Riser Build

[jayb]

Since I've already spent $1200 on the T&D setup I don't really want to switch to a different style of rocker.  Besides, the Blue Thunder heads are specifically designed to use the T&D rockers.

Looking at the T&D setup, when they offset the rocker they make the rocker itself wider.  To do that on the non-offset side, everything would have to change, including the stand with the studs that bolts onto the head, the individual rocker shaft, and the rocker arm itself.  So I don't think there's much of a chance to get an offset rocker in on the problem side of the port. 

I think I can live with a slight bulge in the port, and not really loose much, if anything, in horsepower.  We're only talking about a bulge .050" into the port.  Joe Craine also suggested that I could increase the height of the port at this point so that I didn't lose any cross sectional area.  That would also be a fairly easy change in the CNC program.

[XR7]

Yes T&D does offer offsets in both positions.... I have a set of T&D on a BT MR head that are .250 offset on the intake like yours Jay, and .080 offset on the exhaust. I did order these custom, but I think almost all T&D stuff is made to order for us FE folks. I was worried you may go through the port with the pushrod tube! I do like tipping or aligning the port on the manifold adapter to the head like you are doing, makes perfect sense. Blair Patrick told me he usually has .180 offsets in both directions... I see why now. I used a 180 offset lifter for the intake lifter and a centered for the exhaust, these are Comps new "Elite" roller lifters and you can exchange the pushrod cups (without tools in a few seconds) to either direction offset or centered.

I can send you a .080 rocker to try and dummy it up, to see if it would work better for you. I won't need it for awhile. It is a standard width body (they do make different width though) with just the adjuster offset so I would think it would fit on the shaft and stand. My shafts and stand look the same as yours as far as spacing of the studs, but not sure if exact.... I would maybe call T&D and talk with Sheldon to see if the stands are the same or if they make several different ones for the BT heads (I wouldn't think so but...). I would think the stands would be different for dual .180 offsets because of where the center bolt on each shaft would be located in a different spot.

I think you can buy just the rocker bodies separate. They would have the bearing and adjuster with it, but no stand. I think they are around 55 bucks each... so $440 for 8 exhaust rockers.

I was also thinking you could adjust your CNC program and maybe not tip the port so much, or gradually change directions to make a sort of turn or (short side radius sideways) to the manifold to correct to straight... to line up with the manifold runner ports. You have to change directions at some point as not all runners (the outer 4) will have a turn to make a straight shot at the head. Sort of like this...   ( (  versus this... / /   I don't think you have to make the complete turn, just 1/2 of it or so, gradually over the 2" thickness of your head plate, or adapter, or port plate.... whatever you want to call it.

On Randy's tunnel ram that he made for the BT heads, he used 1 1/2" adapter plates and then welded the front and rear china walls to it, then a tunnel rams with flanges that bolted to it, so basically a 2 piece "AKA" PSE type deal. He still had heat warpage and shrinkage, requiring a ton of machine work to get it right. The intake top was easy to correct the the lower was a bear. On the Schwartz/Patrick tunnel ram, it is a bolt together deal and completely CNC machined. That way there is no weld distortion. I think he has done a few tunnel ram tops where the flange is machines, then the tops, where they are then welded together about 2" away from the flange part way up the runner, they are thin and the same thickness, welding easily without warpage at the flange... like what Mario was talking about further up the thread.

I like the lower part of the plates where you leave a step on there to the china wall and for the valley tray. I think if there was a way to make a 45* lip instead, and then have a valley tray lay on that and have a few bolt holes along the side to secure to the head plate without welding might work out well. Most of the Yates/Cleveland and Ford/Chevy/Dodge Nascar  setups are like this. They run the water out of the head, bolt a valley tray to the lower part of the heads, and the intake is a "spider" or runners with flanges only. I would not run water through your plates, I would block it there, and drill and tap the heads, run a 12 or 16 AN line out to a Y or remote thermostat housing and then to the radiator. Make plumbing and welding machining etc, easier on the manifold adapter or base. Only thing you have to worry about is locating the distributor hole and sealing the china wall and to the heads. I have a few pictures of the Schwartz/Patrick billet valley tray and it does bolt to the head plates, no welding.

[jayb]

Well THAT is very interesting information.  Do you have a photo by chance of the offset rocker you described?  Also, any way you can measure the width of the body of the offset rocker?  If it was the same width as mine, I could just get the same rocker from T&D, and that would solve this problem.  If you can't get at the rockers to measure them, no sweat, and thanks anyway.

Looks like I'll be talking to T&D soon...

[XR7]

I don't have a photo handy but can sure get one later. I did measure the body width and it is .900" wide. There are thin shims on both sides, outside the bearing, inside the snap rings on the shaft. I'd say the distance between the two studs to mount the exhaust rocker to the shaft, is approx. 1.570", center to center. The intake rocker width is 1.150" and is actually a 1.8 ratio, the exhaust is .175.


How do these dimensions compare to yours?


I think they would have .125 offsets also... but, most likely that would have a wider body.

[jayb]

I measured mine tonight, and they are the same as yours, with the 0.900" wide rocker arm and about 1.570" center to center on the studs.  My rockers are both 1.75:1 for the ratio. 

I'm going to call T&D about this.  If I could get rockers with the same offset as yours, .080" towards the outboard side of the port, I wouldn't have to change the port in the spacer plate.

[cdmbill2]

Jay, hopefully the T&D deal works out on the pushrod hole location. The other factor that might help is going to a lrger diameter lifiter, a .904 or .932 with an offset push rod cup would give even more room.

I am really pleased with how the .904's worked on the 588" build.

As to manifold, XR7's idea about a dry manifold, e.g. the wet parts are separate along with a vally tray would really simplify a lot of other considerations and allow you to experiment wi the dry side only in terms of runner length, plenum configuartion, carb or TB or IR etc. You might want to add a bolt hole or two in the head to make the attachment process easier and cleaner or look at bringin water into the head from the front like the C460 and other 385 style heads.

I know all this moves away hrom certain FE centric design ideas but you are pushng the evelope anyway and most of these parts are after market custome stuff as well instead of NOS unobtainium so why not?

Keep up the great work its inspiring for me too.

[jayb]

In fact I spoke with T&D yesterday, and they confirmed that I could get those rockers with the offset adjuster, just like XR-7 said.  So, I have ordered a set, and I think that will eliminate the need for any bulge in the port wall.

I actually would like to go with a larger diameter lifter, but the short block is already together and I've had the lifters for a few years, so I didn't want to tear it all apart and remachine it for the larger diameter.  But its good to know that they work well; maybe if I go through this engine again in a few years I'll machine for the larger lifters, along with upping the compression, reducing ring tension, etc.

After your post I looked tonight at the front of the heads to see what would be involved with just running the water straight out.  Looks like it could be done, but I could also bring the fitting out the front of the port plate block, which would avoid cutting the head for a fitting.  I think I'm going to go that route.

Bill, I'm definitely not married to the base FE design, so modifications like this are not off the table for me.  I just want to go FAST 

[XR7]

Well I'll try to insert a couple pictures here, but if they don't load... I'll just send them to you Jay.

[jayb]

Yep, that's what I need, all right.  Thanks for the pics!

[machoneman]

Way cool, XR7 to the rescue! I like the idea of not tubing those sidewall cutouts that could impede airflow.

[XR7]

Happy to help, in any way I can.

I was curious what the cam specs for this HR build are Jay. I am thinking it would be pretty stout to take advantage of those awesome flowing HR heads.

Was also wondering how long your valves are... I went a little longer than normal, @ 5.550" and still need to mill about .030 off the rocker pads on the heads for .822 net lift. Your valves must be even longer if you need to shim, and/or less lift. The T&D shaft height gauge for the FE is designed for .650 lift and is stamped as such. For lifts over .650, the shaft height should be lowered by 1/2 the difference, or if less lift.... raised up with shims by 1/2 the difference. So if it were .850 lift as an example, the shaft should be below by .100 according to the gauge when in contact with the valve tip. You probably already know all this, but just find it interesting how your set-up is so much different than what I have here. I guess that is why they supply the gauge, component stack ups for individual builds are different. They are basically after a "mid-lift" type rocker geometry to where the rocker is in the center of its travel pivot or arc, exactly at 1/2 or "mid-lift".

One last question (for now)...LOL. How long did your push-rods end up being and what wall thickness? OK, sorry... that is 2 questions.

[jayb]

The cam I have for this engine is a ZT series Comp mechanical roller, with the 4821 lobe on the intake and the 4827 lobe on the exhaust.  This is 272@.050 on the intake with lift in the .720" range, and 282@.050" on the exhaust, with .730" lift.  Funny you should mention the cam, though, because I've been rethinking it lately.  I'm using the 26099 Comp springs, which are good for about .800" lift, and I have enough piston to valve clearance to accomodate that, so I've been giving some consideration to going bigger on the cam.  The only issue is that I have had to grind the rod shoulders already for cam clearance with the 4.500" stroke, and if I go too much more on lift I might end up without sufficient clearance there.  So right now I'm leaning towards getting a different cam for this engine that uses the 4827 lobe on both intake and exhaust.  This would get my horsepower peak higher in the RPM range; I'm thinking with the existing cam it might peak down around 6200 or so, and I'd like to see the power peak at 6800 instead.  Hard to say for sure until its on the dyno, of course...

On the valves, I can't remember how long they are, but they are very close to stock length.  However, I did use +.050" retainers to get the spring installed height at 2.050".  Thanks for the info on the T&D rocker gauge; I knew that the .650 on the gauge indicated .650 lift, but I did not know about raising or lowering the shaft to compensate for more or less lift.  I ended up eyeballing the motion of the roller tip across the valve as I tested for different shim heights, and I ended up with less shim than I needed to make the gauge perfectly square, so it sounds like I went in the right direction.  It will be nice to be able to measure and calculate exactly next time I mock up.

My pushrods are 9.55" overall length, but I'm currently using some SBC lifters in the engine, so my pushrod length will probably not translate directly to yours.  That's another thing I'm thinking about changing this engine; since I bought the parts for it, I switched over to Crower roller lifters, and since I can get FE Crower lifters with the offset pushrod location I'm thinking about buying a set of those and putting those SBC lifters on ebay.  Wall thickness of the pushrods is unknown, but Smith Brothers said they were good for up to 900 pounds of open spring pressure.

[jayb]

I had a big change in plans on this engine this week.  About a week ago I spent some time talking to Blair Patrick about my camshaft dilemma.  When I caught Blair he was in the truck coming home from a dyno session where his latest 511" FE made over 850 HP (I hope to post some details on this engine in the next few days).  The engine wasn't all that radical, and other than Blair's superior engine building skills, it didn't really get any overly specialized treatment, just a really good set of Edelbrock Pro-Port heads and a tunnel wedge intake with a couple of 660 center squirter carbs.  The cam was relatively small at around 270 @ .050", and the engine peaked in power at 6400 RPM.  My concern with my camshaft is that it may be too small to make power where I want it; with the extra cubes in this engine, and the ports in the heads, I wanted to be making peak power at around 7000 RPM.  But my cam has about the same duration @ .050" as the one in Blair's engine, and his engine is smaller.  No way I was going to peak in power at 7000 RPM with this cam.

Another cam problem was that I really wanted to run more lift in addition to more duration.  The head flow of the high riser heads is still increasing at .800" of valve lift, and my cam has intake lift of around .720".  And I can't run any more lift with the big stroke on the crank, because the rods are within .015" of hitting the cam lobes.

Sitting over in the corner of my shop is my third engine project.  I will start posting on this one shortly, but basically it is a smaller SOHC, that I plan to put back into my Galaxie this spring.  It is apart for a new set of pistons and a general freshening up, including a grind on the 4.375" stroke crank. 

Over the Thanksgiving weekend it dawned on me that I might be able to play a game of "musical motors" with the high riser and the smaller SOHC, to the benefit of both engines.  If I swapped cranks in the two motors, I would gain an addition .062" of clearance from the cam lobes to the rod shoulders in the high riser, allowing me to run a much bigger cam.  I would lose 15 cubic inches and the associated horsepower, but I was pretty sure I'd pick up more than that with a cam swap.   On the smaller cammer motor, bore is 4.285, and the 4.500" stroke would get me to 519 cubic inches, which the heads on that engine will definitely support. 

The bad news was the associated costs.  I'd be setting the existing pistons in the high riser engine aside in favor of a new set of slugs.  But I kind of wanted to increase the compression ratio on the engine and go with a smaller ring package anyway, so I guess I could handle that.  But on the smaller SOHC, I had just received my new pistons from Diamond, and didn't want to order another set.  This meant shortening the rod from 6.700" to 6.637" in order to maintain the correct piston height in the bore.  This was a custom rod, and was probably going to be expensive.  Hmmm....

I called Blair back up and bounced some of these ideas off him.  He agreed that I would get a net gain if I dropped cubic inches and picked up cam on the high riser engine, and thought that 900 HP wasn't out of the question for that engine.  THAT would be cool...  He had a couple of grinds that he thought would work well in the engine, and he's going to send me the specs in the next few days.  And he also had a great suggestion on the rods.  Crower makes a forged 1000 HP capable rod in a 6.625" length, just a little shorter than what I need.  Blair suggested I just get a set of custom Cometic head gaskets, in a .027" thickness instead of the .040" standard thickness.  This would get the piston to chamber relationship back where it was supposed to be if I swapped in the 4.500" stroke crank and the off-the-shelf 6.625" rods.  I wasn't sure if Cometic made the custom thickness gaskets available in the SOHC version, but it was sure worth checking on.

Next day I emailed Cometic, and sure enough they could whip up the head gaskets I needed.  So, I pulled the trigger on the musical motor deal.  My 545" high riser project is going to morph to a 530" high riser project, with a bigger cam and more compression.  And my smaller SOHC is going to get a little bigger as a result.  Plus, I'm a lot happier with both projects after this decision.  I should get more horsepower out of both engines!  I'm pretty psyched up about this...

[plovett]

Sounds like a good plan to me.

I gotta ask though, how do your Hi-riser heads and intake compare to Blair's Pro Ports and intake?  I'm not sure I'd make an ironclad statement that since a certain size cam peaked at a certain rpm in a smaller engine,  the same size cam must peak at a lower rpm in a bigger engine.  I think if your induction system has more capacity it may rpm the same or even higher than the smaller engine, with the same cam.  I'm sure you've taken all this into account.  Just curious about it.

paulie

[cammerfe]

Hey Jay---

I just read back through this thread, and had a thought. If you just bend the pushrods over a little bit, you'll eliminate the interference with the holes and not need to go for all these hardware changes!!

KS