I thought it was really interesting seeing the difference between just being bored, and being honed.



I don't think I'll worry about having the rods shot peened/grinded, etc. Seems like a cool idea, but I imagine they're plenty strong as is.

 

When is AB going to bless us by conveying his cam choice to the forum?

 

No new updates yet. Stopped by the machine shop this morning and he's just been swamped with work, and putting in 7 days a week.

He said for balancing that he's going to need the flywheel and clutch. Unfortunately, they're bolted to my current engine! I bought a new flywheel/clutch about a year ago and don't know if I really want to be buying a whole new setup. However, I don't want to pull it off so he can balance it or I'd be without a vehicle for too long of a long time.

Thoughts? I know the 300 is zero balance, but that doesn't mean everything's perfect. Should I just bite the bullet and buy another flywheel/clutch setup?


As for the cam, I still haven't decided. Kinda put that on the shelf for a bit. =P I am thinking something comparable to (if not the) Comp 260. He's an Erson/Comp reseller so I should list out all the lift/duration numbers, etc. and compare them all.

 

That can only be answered by you. I'd ask him if you could make an appointment of sorts so that when you brought them in, he could get on it right away. If it were me, I'd probably spring for a new setup because of the time and aggravation involved in pulling it, then back in to the running truck.

Do you have another way to get around? Is there someone, maybe another FTE member, that has a flywheel laying around that you could use in exchange for the one in your truck now?

The cost of a rental car can add up to what a flywheel/clutch would cost. On that thought, is there either someone from who you could borrow an extra vehicle for a bit, or maybe there's a "rent a dent" type car rental place around you someplace.

 

Thanks for the thoughts.

I won't be pulling my current clutch setup out to have it balanced, I can't have my Bronco down that long since I'd probably leave it out until the engine was done (which has been a slow process).

I guess I was meaning more along the lines of does a zero balanced clutch setup need to be on the engine to balance everything? Or would it still be better to balance it all together? If so, I'll probably bite the bullet and get another setup.

I do have the old flywheel / clutch that came off the engine in my garage, but I imagine it's not going to be exactly the same as the one I'd be putting back on since I wouldn't reuse it.

 

Oh, sorry; yes, I misunderstood. You hate to buy a new one as had planned to reuse the fairly new setup that's in there now. If you bought a new one, then a perfectly good setup would be extra no matter what.

Dunno if a zero balance needs the flywheel to do a precision balance. Perhaps if no one knows here, then a few calls or emails to those in the business should be able to answer "more better".

Good luck; I'm interested in that answer too, and can be fairly sure others here would also like to know.

 

I personally don't think balancing the crank with the clutch is a good idea. So what happens if the clutch needs to be replaced? Are you going to pull the crank and have it all rebalanced?

I don't think I'm going to have my crank balanced. I'm just going to balance/weight match the rods & pistons. I just don't feel that's it's really needed. Unless you are building a high rpm race engine. I just feel the money is better spent on other parts.

But if you are having it done just give them the flywheel and Dampner you are going to run. Just make sure they aren't V8 parts.

 

Go with the Erson RV10H. It has the needed 280 adv. duration to keep your dcr down, and will also wear easier on valves and seats with a more gradual lobe ramp. It also has relatively mpg friendly lift at .448". It would be torqier (is that a word?) with a 108* lsa, but what the heck.

It says for heavier vehicles, towing, city, mpg, rpm range from 1k up.

 

ETA on this build? It's pretty badass!

 

And for me, that begs the question: what do you do with the clutch disc? Assemble it too? What centers it up?

I have never had an engine balanced with the clutch. Conversely, I have never had a flywheel balanced with the rest of the engine.

 

Thanks! I'm hoping to have it done within a month or two. It's moving slowly and as funds permit, but I like that that gives me time to plan and change plans accordingly.

That's definitely something to think about. Because, yes, what does happen when I need a new clutch? Is it going to throw off the balance of the engine? It'd be a lot easier to zero balance the crankshaft and then take down a flywheel/clutch/pressure plate and have them spun up and checked for zero balance than to always be trying to balance the crankshaft and clutch assembly together. I would like the crankshaft balanced though, even if it is separate.

I imagine that simply may be an errant thought he has from working on race engines that only see 1000 miles a year.

The engine's also only going to be hitting 5k RPMs max.

No worries on V8 parts... I don't have any!

I'm not sure how balancing works, but if it's done while in the block, doesn't the pressure plate just hold the clutch disk in place? Every time I've put a clutch in, there's a centering tool that's put in place.


But either way, you guys make some good points. I may dissuade the idea.

I like that recommendation. I need to figure out what my DCR is with the Erson cams. The number used in the DCR equations isn't directly supplied like it is with the Comp cams so I haven't done it yet.
I do find it interesting how much more advertised duration Erson cams have than Comp cams. Erson's cams are 280 - 292 whereas Comp's are 252 - 268. Granted, when looking at the lift @ 0.050", they're much more similar.

Comp 252
Intake @ 50 - 206
Exhaust @ 50 - 206
Valve Lift - 0.433
Notes - Good torque and mileage for 240-300. Excellent throttle response.

Comp 260
Intake @ 50 - 212
Exhaust @ 50 - 212
Valve Lift - 0.447
Notes - Excellent torque and power for towing in 300 c.i. Smooth idle.

Comp 268
Intake @ 50 - 218
Exhaust @ 50 - 218
Valve Lift - 0.456
Notes - Moderate performance camshaft for 300 c.i. Strong in mid range RPM. Noticeable idle.

Erson RV10H
Intake @ 50 - 208
Exhaust @ 50 - 208
Valve Lift - 0.448
Notes - Broad power range. City and expressway driving and towing. Cars, wagons, pickups and heavier rigs. Good idle, throttle response and fuel efficiency.

Erson TQ20H
Intake @ 50 - 214
Exhaust @ 50 - 214
Valve Lift - 0.478
Notes - The "Performer". Superior low and mid-range power. Good idle, fuel efficiency and drive ability. 4 barrel carburetor and headers recommended.

Erson Hi-Flow AH
Intake @ 50 - 220
Exhaust @ 50 - 220
Valve Lift - 0.504
Notes - Works great in slightly modified engines with up to 9.5:1 compression. High-lift and short duration builds good torque and mid-range performance.

 

Okay, I did the math. Dynamic compression ratio is calculated from the Advertised duration, not the duration at 0.050", so it does make a difference that the Erson cams have a much bigger advertised duration.

The Intake Closing Point is what is used to calculate the DCR.

ICP = (Advertised intake duration / 2 + Lobe Separation) - 180 - Degrees advanced

These are all calculated with a 9:1 static compression ratio.

Comp 252
Intake/Exhaust Duration - 252
Lobe Separation - 110
Advance - 4°
Intake Closing Point - 52
DCR - 7.87

Comp 260
Intake/Exhaust Duration - 260
Lobe Separation - 110
Advance - 4°
Intake Closing Point - 56
DCR - 7.69

Comp 268
Intake/Exhaust Duration - 268
Lobe Separation - 110
Advance - 4°
Intake Closing Point - 60
DCR - 7.49

Erson RV10H
Intake/Exhaust Duration - 280
Lobe Separation - 110
Advance - 4°
Intake Closing Point - 66
DCR - 7.17

Erson TQ20H
Intake/Exhaust Duration - 292
Lobe Separation - 111
Advance - 4°
Intake Closing Point - 73
DCR - 6.77

Erson Hi-Flow AH
Intake/Exhaust Duration - 284
Lobe Separation - 110
Advance - 4°
Intake Closing Point - 68
DCR - 7.06

All of the Erson cams really help to keep the dynamic compression ratio down. That really may be something to consider.

 

I thought the Erson RV10H has 220 duration @ .050. What I learned from Pmuller9 is that the adv. duration, when far greater than the @.050 number, indicates a more gradual lobe ramp, making for less wear on v.seats, etc. I would have that cam ground @ 108 lsa to give more down low power.

Crower will do make it for less, $181 iirc. Call Jerry at Crower. (That's the Blondie grind! 280 adv., 220@.050, 108 lsa +4*) refer to my post on other forum for clarification.

*I learned that with Ford's small block 6's Ford ground the oem cams at 107.5 lsa for the above reason. Interesting stuff. That was stock.

 

Hmmmm I must be getting old lol. The Erson RV10H sounds like what I would be interested in my F250. It'll be my tow a camper and a 18ft Champion bassboat rig. Occasional wood truck if my knees hold up.

 

This is what I was going off of:

USA Performance Parts - Erson 6 Cyl Ford Hydraulic Cams

RV10H specifically:
Ford 6 Cyl 240-300 CID Hydraulic Cam & Lifter Kit - 208/208° @.050 .448/.448 li - USA Performance Parts



That makes sense on the advertised vs the @0.050. I kept up with your cam thread over on fordsix for a while, but haven't looked at it in a bit. I'll have to reread it. That'd be cool if there was one that was close to what you were coming up with, and then just tweak it a bit! 110° seems to be an extremely popular lobe separation for the 300. I'm curious why that is.

Either way, I kinda dig that cam. I also like that the greater separation puts less stress on things.