Looking at having the cam in the 83 D-150 re ground to the spec's that Doc posts for the RV10 or RV 15

being an 83 it is a hydraulic lifter motor and plan to keep that one that way. The 83 hydraulic cam is on a 105 LSA, so it has that going for it, It is ground 3 degrees retarded, I could maintain that and set it 3 advanced to get it straight up. I know the service history of the motor since new, so likely the OP drive gear and cam journals are good.

RV-15 http://www.dutra.org/dutraorg/pictures/ ... am60bd.jpg

RV-10 http://www.dutra.org/dutraorg/pictures/ ... m-212-.jpg

been looking around the internet, found statements like,
1) mechanical ramps are ground less aggressive initially to take up the valve train clearance
2) hydraulic grinds are less aggressive at maximum valve opening to keep the lifter on the cam
3) you can use mechanical lifters on hydraulic profiles
4) don't use hydraulic lifters on mechanical profiles,,and so forth,,,

Basically what, if anything needs to be interpreted on the RV10 / RV 15 spec sheets to make that grind compatable with a hydraulic application?
Would like to know, so when I am specking with someone at a cam shop, I can get a feel if they actually know what they are doing, in this case.

also, is the RV-10, as shown really a RDP cam,, I see the exhaust as having more duration than the intake on the spec sheet.

thanks

I will be following this thread with interest since I will also be building a hydraulic motor with a custom cam profile for my brother's Duster.

I have done a bit of research, and the biggest problem I have come across is maintaining the proper overall height of the cam since the rocker arms have no adjustment. Most custom hydraulic cam cams require the fabrication of custom length pushrods to deal with the change in profile of the camshaft. Too tall of a lift and the lifter plungers will bottom out and the pushrods will get bent. Too short a pushrod and they won't fit or you won't get the full advantage of your cam.

I would love to see some specs of just how much play there is in a hydraulic lifter setup so people could figure out just how much material can be ground off a hydraulic cam when designing a custom profile. I am planning on doing the measuring myself, but if someone wants to do it before me, I won't complain.

One thing I will say is that on the cam I had reground to the RV-10 profile and put in the motor in my brother's van, the lifters are much louder than a stock mechanical cam. I would love it if hydraulic lifters would quiet it down.

To really get a good idea of a mechanical cam's characteristics you have to find the valve events with the lash set as it will be run. You can have two mechanical cams that look nearly the same on paper, but if the advertised duration is found using different lifter heights and/or the lash is different the two cams can have very different performance characteristics. So if you want to duplicate the performance of a mechanical cam you need to find the valve events and see what it takes to reproduce that in a hydraulic grind. Typically a mechanical cam will have more advertised duration to make up for the motion lost taking up the valve lash.

I like that Erson gives the duration at lash. You should be able to spec a hydraulic cam with those same advertised duration numbers and get really close to the same performance, but I would check the duration at .050" lift as well. If you give up much duration at .050" you'll lose performance. To duplicate the RV15 I'd try the Comp Cams Extreme Energy 262°/256° lobes as they are 218/212° @ .050" lift like the RV 15, but better valve lift at .455"/.447". I'd also run the lobe centerline at 106°. The idle won't be quite as good as the Erson mechanical at 110°, but I believe the torque will be better across the power band. I'd start with a 102° intake centerline with this and no less than a true 9:1 compression ratio.

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Joshua

Reed
who reground your cam? were you satisfied with the work. I know that Josh recommends Oregon Cams, they are in the running, but I was wanting to get my "ducks" in a row prior to making a decision.
Also on the push rod length, custom push rods are part of the plan. I know that there will be some milling of the decking surfaces, to get in the high 8's static compression ratio, this needs to stay a reg gas vehicle. Will the milling combine with the smaller base circle on the cam to allow the stock pushrods to be carried forward?
don't know if I will be able to tell until I start putting parts together and actually measure lifter pre-load.

Josh
you mentioned the Comp cams,,will a cam grinder have those profiles, I am wanting to re grind my existing cam.
Am I correct in thinking that I can control the dynamic compression ratio by physically advancing / retarding the cam?

the good news is,, nuts and bolts are about ready to turn on this 83 D-150 project. thinking that if I start in Feb, could be done by August, de-bug in Sept and drive down to Clay City in Oct,, sounds like a plan anyway.

Oregon Cam Grinding has masters which are duplicates of the Comp Cams lobes I mentioned and should be able to do the job for $70 plus shipping.

If you mill to get the compression ratio up near 9:1 you're going to take a lot more off the head and/or block than off the base circle of the cam. I should take one of my hydraulic lifters off the shelf and see how much travel they have.

I recently traded a mechanical cam core and valve gear for a hydraulic cam core and valve gear. I'll probably use these parts on a turbo build. Might even do EFI and a knock sensor.

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Joshua

I had Delta Camshaft here in my hometown of Tacoma, WA do the regrind.

http://www.deltacam.com/

I took them a core 1964 stock 225 cam and $90 later I had a cam ground to the Erson RV-10 specs and 12 reground lifters. I was only a two or three day turnaround on the cam and they had the lifters in stock.

My only complaint has ben the excessive lifter noise. However, running Mobil 1 synthetic 5W-30 oil has quieted them down greatly. Also, my understanding is that it is the profile of the RV-10 cam that makes the lifters noisier. Aside from that, the cam had been excellent. I run the valve lash at .012 intake and .022 exhaust. It gives 20-21 inches of vacuum at idle in neutral and has excellent power.

I would love to find a comparable hydraulic cam for my brother's Duster.

Reed considering the engine in your brothers van
besides the cam,, what else was re-newed or upgraded in the engine,
can you quantify how much of the added power is due to the RV-10,, why did you choose that one instead of the RV-15?

thanks

Although the van is a 1983 vehicle, the motor is a 1976 mechanical lifter motor. The cylinders have been bored .060 oversize, the cylinder head has been rebuilt with Ford 300 valves (but no porting ) but no milling to increase compression, it is currently running a "Super Six" distributor, it has a Ford e-core coil, it has dual exhaust merging into a single 2 1/2 inch exhaust pipe, it was upgraded to a two barrel intake with a NOS Holley 2280 carb. The cam was also advanced six degrees, if I remember correctly. I also installed a factory clutch fan and welded up a cold air intake for the engine.

Future modifications include upgrading to HEI ignition and fine tuning the distributor advance curve.

I cannot quantify any power difference. When I first started bringing my brother's an back to life a few years ago, it was a non-driveable vehicle that had sat in a storage lot of about five years. The best thing it had going for it was the rebuilt short block motor that I had installed about eight years earlier. It got 3 MPG and was a single barrel carb with stock exhaust. The transmission was shot so it couldn't even move. Too much has been changed on the van for me to give you an accurate description of any power difference. What I can tell you is that the van now hauls a band made up of five adults and all their gear (guitars, amps, drum kit, etc...) and does fine on the highway and around town. It is not underpowered for its job, and the fuel economy is 12-15 MPG mixed driving. With 3.2 rear gears and a worn out 1973 904 transmission, it cruises around 27-2800 RPM on the highway doing 65 or so.

I went with the RV-10 because that was what was recommended to me to give the best low RPM torque and fuel economy. I have been heavily influenced by Aggressive Ted's motor build. If I were going to build another truck motor for power and economy, I would build it exactly the same but keep the stock size valves and only overbore the cylinders as much as was necessary to clean them up. I would also Take the time to get the head milled to increase the dynamic compression ratio to a smidge over 8:1.

I am only referring to things said earlier in the forum, without having any personal experience in the matter, but isn't the general complaint about cams from Clifford, that they in fact sell hydraulic spec cams? Could this be a case where you actually should take a closer look at those specsheets? Just thinking loud...

Olaf.

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Aspenized

Bigger valves,no pocket porting,and not increasing the compression doesnt make sense to me.Bigger valves,pocket porting,and higher compression with the rv 15 cam is a proven winner combo.My Opinion.Mark

You are right. The motor was assembled over a period of about ten years using parts from other projects. First, the motor was a stock short block except for the double roller timing set and the oversize pistons. It ran a stock, unrebuilt 1974 head. Then I had the big valve head built but before I knew about how important porting was. Years and years went by and then I decided to try a custom cam, so I opted for the RV10 cam grind since the motor is a daily driver in a van and not a 1/4 mile racer. The motor truly never gets above 3500 RPM, and rarely over 3000 RPM. After running that for a while, I decided to try bumping up the compression. I had a head rebuilt with stock valves but with lots milled off to raise the dynamic compression ratio to a bit over 9:1. I must have messed up the math somewhere because with the milled head the motor pinged like crazy even on premium with the timing back way off and two heavy heavy distributor springs and no vacuum advance. So back on went the unmilled big valve head, the timing got advanced again, and now it running pretty dang good. Maybe not optimal, but I am working with what I have and within my budget.

If I were to build a motor from scratch, I wouldn't put it together like the one in my brother's van. Knowing what I know now, if I was building a motor for torque and fuel economy in a daily driver van, I would keep the stock valves, only bore enough to clean up the bores, port the head, install a RV10 or RV15 cam, and mill the block to get a low or mid 8:1 dynamic compression ratio. I would stick to a single barrel carb, or maybe a small two barrel. That isn't a recipe for high RPM performance, but that isn't what I am going for.

spent some time looking over the Oregon Cam hydraulic lifter spec sheet

http://www.oregoncamshaft.com/Hydraulic-Cam-Specs.html

the combination that I see that may give the closest to a rv-15
would be to use the
1410 intake, as the intake profile , would get 218 duration at .050 and .441 lift at the intake with 1.5 rockers
1333 intake as the exhaust profile, would get 212 duration at .050 and .447 lift at the exhaust with 1.5 rockers
would that make sense?

Josh, you mentioned
1) the Comp Cams Extreme Energy 262°/256°,
are these the one's you thought would match those? When I called Oregon cams today, Ken mentioned some new profiles, not on the sheet on the web site.
2) lob center line angle (lob separation angle) of 106 vs the RV 15 of 110, am I correct in thinking the increase in torque will come from, given a X value for a intake and exhaust duration, the closer these are brought together there is more time when the intake and exhaust are both open at the same time, and as a consequence the intake closes later with respect to crankshaft position,,so the cylinder will have more fill time,, also the exhaust opens sooner, so there is a loss of blow down,, but it is a long stroke motor anyway...I have struggled with this one,,,I need some help here, as to increase torque across the power band, one would close the intake sooner,,
3) the comment "intake centerline of 102 ,, has to do with degreeing the cam 2 degrees advanced on installation.

is the analysis wrote out in 2 and 3 on track?

thanks

I would have Oregon grind you #1333 only swap the intake and exhaust lobes and close up the centerline to 106°. Then it would be 218/212° at .050" lifter rise and .455/.447" valve lift just like the Comp Cams XE lobes. I would bet $1 those lobes have the same profiles, but the advertised duration is different because of different checking heights.

A narrower intake-to-exhaust lobe centerline increases overlap, opens and closes the intake valve sooner and opens and closes the exhaust valve later. The idle may not be quite as smooth as with a 110° lobe centerline, but it will make more torque so long as the exhaust system is free flowing.

A 102° intake centerline means the intake valve is at peak lift 102° after TDC. This is considered 4° advanced if the lobe centerline is 106°. Since the factory cam is ground retarded you will need offset bushings or a multi keyway crank sprocket to get the cam timing correct.

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Joshua

That's what I'm doing on my build, hope it works out as I've read it should

I had the head shaved .090 - but didn't put larger valves in DANGIT!
So stock valves but a complete rebuild
I ported and polished the head myself.
Pistons are .060's
New crank, etc. block decked a little to straighten (about 10g's).
Two barrel intake with a 500cfm Holley - 2305
Plain jane exhaust into a 2.25" single pipe
Msd6AL ignition
Rebuilt 727 automatic with shift kit - took out the three on the tree
New drive shaft
Rear end completely rebuilt with 3.55's

Here are the specs for the cam:
ISKY Part No. 152116
Grind VA-160

Cam Lift - 298
Valve Lift - 448
Dur - 264
050 Dur - 228
Lobe Center - 109
Valve Lash Hot - .018

This is the description for this cam on the ISKY web site
ISKY - Grind No./Type VA-160 SOLID
Good mid-range power cam.
Fair idle;
3.55-3.73 axle ratio.
RPM-Range 2500-6000
Valve Lift - INT .448 EXT .448
Valve Lash Hot - INT .018 EXT .018
ADV Duration - INT

It runs pretty well - at times - and others it takes a dump on me! All in all though - I REALLY like it!

best I've done at the Redding dragstrip was 17.36 I think ?
I'm running 15's on the rear and 14's in front (makes stearing a little bit easier)

dan

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"I may be slow, but at least I'm not very fast!"
'69 A108 - 225, 727, 3.55, MSD6AL, a.k.a.-the brick