HOW TO: BBC VALVE SPRING UPGRADE. DOES SPRING RATE MATTER? 

I live for the big block Chevy content he drops

I’ll take the air gap any day, that long flat torque curve is what I’m after. 👍🏻

Great test and comparison Richard !!!!

I love what you do man I love how specific you are great practical testing ideas wonderful information for all the shade mechanics

This is a comment because I like comments. It's a really good demo. There is probably lots of guys thinking about getting a gen6 and wondering what a proper head will do.

Man, does anyone else think that Richard's office is the best green screen background ever?

dang GOOD video!... ALL things I've been thinkin about lately...as I'm planning a bbc 454 big oval assembly. BIG THX 💗 richard...you been readin my mind.

I've been running a similar combo for almost 20 years with AFR 305 rectangle port heads, they didn't have ovals back then. Compression the same, and similar 242/248 hydraulic roller but custom grind from Comp with .638 lift, 110 lsa. I use the RPM air gap on it with a 1" open spacer. I liked the curve better than the Victor Jr. since it's primarily street driven and the spacer helped a pinch up top. This combo makes a very fun street engine and has gone a best of 11.38 @ 118 in a 4100 lbs chevelle through a full exhaust system and DOT tire.

I will never own a BB Chevy, but I love these videos. Thanks

🔥🔥Great Info for my Gen VI L29 K2500 EFI motor, Awesomeness Richard 🔥🔥

Even if you're not into big blocks, some of this info is still helpful.

Great explanation as usal

I remember an old mechanic telling me about the problems with the 409 dropping valves. Must've been pretty common, apparently whenever they revved the engine to around 6000 rpm. I learned later that the valve springs were the weak link in the 409 and better springs became available. I have no experience, just a lot of useless second-hand knowledge, but that's the story I heard..

We had a 396 on the Dyno that was in trouble at 5600. Swapped the Comp steel retainers for the Comp titanium versions. Picked up 400 rpm and 30 hp.

Great test, that’s the heads what I want for my 502 for my Motorhome, everything is out of stock now

What about the air velocity on the AFR heads? David Vizard talks about this on his Channel in episode 9. The combustion cambers receive more air when a higher velocity air column rams more are into the chambers as the rpms increase.

Exhaust is a big key If you can't get the exhaust out You're screwed 1.75 exhaust valves on 406 ford heads Woke my 428 ci up back in the 70s

Alot of Area over 500hp after tuning with pedestrian heads and a 541 peak. Good job, Right Cam ...

Could you take the cylinder head flow test data and put it on a graph, with valve lift on the x axis and air flow on the y? It would be really interesting seeing head-to-head (haha) tests done.

Absolutely

I agree on higher spring pressure with HR cams. I'm running 150 closed and 420 at .6 on sbc with 1.7 rockers. PAC 1.275" duals so light weight. Also need to remember if your springs are a little soft your lifter wheel will come off the cam, causing damage and wear. There think there was evidence of this at lower rpm with the softer springs.

I've found on the BBC a weak link is the stand-alone rocker stands themselves. Increasing spring pressures substantially I think requires the use of a stud girdle.

Hard to beat those AFR oval ports for the street. Just for grins overlay a 6.2 LS3 with a 469 cam over the iron rec port head dyno curve. I always thought comparing the LS to a BBC was nonsense, but in some cases not. Once you put the good heads on it it certainly IS nonsense, though!

I've seen that ugly curve drop on the dyno more than once, and with a worse drop off. Some times all that was needed was a .060" shim under the springs to fix it. Some of the worse flat tappet cams are the small Extreme Energy since you wouldn't typically put a big spring on such a mild cam that is intended to peak at 5200.

Can't get over how well the engine responded to the AFR oval port heads. They absolutely blew the big rec port heads into the weeds. I would take that 468 combination with the dual-plane manifold. It gained 30 hp at 4000 rpm, and lost 20 hp at 6500. I think the average power advantage would go to the dual-plane manifold in that case.

Richard, do you remember the lifter return spring idea? They were springs right above the lifters in the early days of roller cams. It was in a mag article back in the day. Every time I see big valve spring numbers, I think of that crazy idea.

Perfect timing Richard. I’m trying to guess my spring pressures. 5500 red line so I can use much softer springs than recommended. Have you tried LS style small beehives on a 454?

I really wounder what the numbers would be with a stock ls gen 454 w the top end kits onnit.

Yea let’s see the difference when you throw a proper cam in that motor to match that head. If you put a cam in it that’s got .800 lift, I’d be curious which head makes more power then. It’s not just a set of heads, you gotta have the other parts to match what those heads are good at. This cam was engineered better for the afr heads. With a higher flowing head, you’ll make more power with a bigger cam and at higher rpm.

Really enjoying seeing info on how to keep the Old Skool relevant with modern engines. Curious...did the AFR heads want the same amount of timing as the rec ports?

Richard. Did ya'll use the rod bolts in the SpeedMaster connecting rods or did you upgrade to ARP's?

OHC engines use valve springs like the OHV engines. Yet, they don't suffer from valve float until much higher in the RPM range. Why is this? The OHV has the lifter and pushrod linking the cam to the rockers unlike that of the OHC. Obviously those components are the real issue that needs addressed. Placing higher pressure valve springs is just a bandaid on a bullet wound. And, you CANNOT "cure valve float." You can defer it later in the RPM band.

in your opinion...do you feel the AFR oval preformance heads would be a significant amount more representative to what the 049 stock ovals would do... when compared to those rec port head? do you feel the 049 heads w/some port smoothing would work well and adequate to a solid roller 255@.50/ .680 lift (7000 rpm range) ???

Put an air hat on that 5.9l magnum, i'd like to see the actual cfm that engine is pulling at the various levels of modification.

Oh snap,

What happened to project Nova?

My bell rang... That means a video posted by Richard.

Isn’t the purpose of a green screen to enhance a background? Silly Richard. You crack me up 😂

What's your experience with those stainless style rockers, are they better/worse than alloy ones?

Do you build engines or put together parts for certain up ranges for payment?

I would like to no what a 4 7 swap firing order cam and a4hole super sucker 1inch spacer on single plane intake would make I believe the cam will load and unload the cylinders more efficiently more power with the. A. F. R head thank you I watch all the time

A 1.8 ratio rocker would help the square port a lot.

I know these are basic setups! But normally today, spring companies want the spring setup within a certain distance from coil bind! 50 thou, 100 thou, whatever they tell you! Unless you’re using a 30yr old spring design! I guess it worked fine on puppy cams. But we rarely setup springs on seat pressure anymore! I’m also wondering why you never mention about cylinder head material grade? If it’s going on a basic rebuild, it probably doesn’t matter! But normally people looking to your channel are looking for the most power possible, not just a rebuild! Also probably worth mentioning about the rocker box of the head! If it’s a rebuild with low power/puppy cam, it doesn’t matter, but put a big shot of nitrous or boost on the engine & some heads will rip the roof of the intake port completely out! This stuff is probably worth mentioning even to the guys doing basic stuff! So he doesn’t have to upgrade head again when he gets bored with the power! Who doesn’t? Thanks for trying to point all the morons straight! I love how you make a video on something, back to back, whatever, than they say, oh I wish you tested with this head/cam/intake! I very surprised you have not said, why don’t you go test it you lazy couch potato mtherfker! 😜😜😜😜😜😂😂😂😂😂👍🏻👍🏻👍🏻👍🏻👍🏻👍🏻

I wonder if AFR uses less spring rate since they use lighter valves? NOT MUCH... PAC Racing Springs #1940 Street Hydraulic Roller Spring 1.550 O.D. 175 lbs. on seat .725” max lift Max RPM 6500-6700

Dont know about gm engines, did they overlook testing during development. This goes with that at susans.

Would afr 305s run better on 454 over the 265s? Thankx.

What about lifters when changing spring pressure

What about valve springs and seat pressure for boosted engines. If cam was left stock and no increase of rpm was sought after.

can it do the reverse..does a too high spring rate or too high rocker ratio make you loose power??

Test don't guess. Cheers!

I contend that flow values at low, mid or high lift, or even average flow fail to express meaningful information given they don’t provide total cfm flow per valve actuation cycle.

I can’t find those valve covers anywhere.

Flow testing heads with just some playdough around the port, I still can't get past that. I'd rather see an intake / exhaust manifold bolted on as there has to be some sort of influence no? .

I thought going over 36 or 38 total was frowned upon? 41 total sounds nuts, but the dyno doesn't lie

The lighter the spring the better. The hydraulic roller is heavier than a mechanical flat tappet and the mechanical has faster lift possible, So if you want to rev it real high forget the roller and go with a flat tappet.

have you tested the benefits of degreeing a cam?

i feel like this video was for me lol

Richard what brand rocker arms

My mrs says she loves BBC, strange she has never owned a Chevy

All srings matter

What did you guys do beat that poor engine for a week straight and port the dual plane and re run the test

Hit it with 200🍼 and you have a 9 second 3600lb street car

Personally I blame squirrels

BUILT!!! It was a built BBC!