490 SBC pumpgas 23* dyno results, need expert "power" advise

[67RS502]

the NHRA Stocker Racer/Builder , especially Chrysler Racers , were doing everything possible to make the then Legal "only" Hyd Flat Lifters
"act" like Solid Lifters

Some NHRA SBC were as little as 0.390"/0.410 Valve Lifts and some Street Hemis were 0.490"/0.480 Valve Lift Hyd Flat Lifters tricked out
to "act" like Solid Lifters

now, NHRA lets them use Solid Lifters in the place of Hyd Lifters

yea, if I was doing a track only deal it would be solid roller or at least limited travel HR lifters.
My "late" (great Christian) ford buddy had a 64 falcon, 302 (stock short block) 351N heads, pumpgas limited travel HR lifters, car ran 10.70
10" verter 410s, didn't have a rev limiter, would shift at 7500, one time shifted it a bit late at 7800, no issues, granted the lobes were mild.

Wheres the LUV for girly rollers?
Theyre fine for 10 and 9 second street cars

[attachment=0]Resized_20190412_095646_5627~3.jpe

Some love of girlie rollers, the old work truck. The comp 260 magnum roller that is still in it was originally installed in the 383 I built for it in the early 90's that 383 lasted many years. When I changed to a 391 and then a 406 the 383 had cracked hyperutectic pistons so it was rebuilt as a 355 for my Dad's '69 Longhorn pickup with the same comp 260 and 1.6 stainless rockers. That mill stayed in the Longhorn till it was sold many years later. The 355 wound up as a band aid engine back in the work truck after I got tired of feeding the 406 premium fuel. I don't think the valve covers have been off in decades. True it is only 260 advertised duration 206 at .050 and .533" lift with 1.6 rockers.

My 420 valve covers haven't been off in forever either, so long in fact that one gasket started leaking.
I like engines were you just add gas and change oil... my kind of street engine.

[Steve.k]

No the last two sets i had bled down not pump up. I contacted the mfg and they said yes was a issue and they working on correcting.They had defective piece that leaked and wouldn't hold pressure. Unfortunately so many sets out before they caught it. Early lifters from years ago fine. Packaged so many who knows where they are today. Id rather set valves than worry about that.

[GARY C]

I personally run hyd flat on what I would consider a street engine, anything beyond that and I go to solid roller, mainly due to cost but also to assure valve motion consistency... If I was to ever run a hyd roller performance engine I would reduce the lifter travel to almost nothing at set up so I knew it was going solid at rpm.

The only way to know for sure how much your giving up with a hyd lifter is to try a solid, most hyd roller performance engine builders run min travel lifters for a reason, even Top Stock with a .525 lift rule, hollow stem 2" valve and 160 seat pressure.

Anytime you increase valve weight and spring pressure you add to the bleed rate of a hyd lifter and decrease it's ability to deliver consistent valve motion, their is a good chance that the engine never sees the full lift and duration of the cam your running and may see different lobes cylinder to cylinder depending on the bleed rate differential between those 16 lifters .

[Orr89rocz]

It always seemed to me alot of guys dont get hyd rollers to work well because something is wrong with what they are doing. Either wrong cam lobes, bad geometry, too little spring or something

So many guys are going fast with them in lsx world. But even sbc guys have done very well. Hell even bbc. I’ve run 7200 rpm at 30 psi boost on the street for 2000+ miles and no issues. 2.10” ss valve sbc deal. Rock solid stability and went 8.20’s at 3800 lbs at 170 mph. There are guys in the 4’s in the 1/8 with them, well over 7000 rpm.

Yeah throw a solid lobe and 300 lbs seat you’ll make power and more so than most any hyd roller. But for a street car that actually sees lots of idle or low rpm driving you cant beat a hyd if you know what you are doing

[GARY C]

It always seemed to me alot of guys dont get hyd rollers to work well because something is wrong with what they are doing. Either wrong cam lobes, bad geometry, too little spring or something

So many guys are going fast with them in lsx world. But even sbc guys have done very well. Hell even bbc. I’ve run 7200 rpm at 30 psi boost on the street for 2000+ miles and no issues. 2.10” ss valve sbc deal. Rock solid stability and went 8.20’s at 3800 lbs at 170 mph. There are guys in the 4’s in the 1/8 with them, well over 7000 rpm.

Yeah throw a solid lobe and 300 lbs seat you’ll make power and more so than most any hyd roller. But for a street car that actually sees lots of idle or low rpm driving you cant beat a hyd if you know what you are doing

I always ran between 200 and 220 on seat with a 2.08 valve depending on what spring fit the head and my budget 266 @ .050 .446 lobe and 1.6 rocker stable to 7700+ this is with the cheapest and lightest lifter on the market thick wall 5/16 push rod and some kind of cheap TI retainers that Herbert use to sell. You can still do a similar set up for around $1000.00

[maxracesoftware]

Do larger hyd/roller lifter bodies, say .903, give up the ghost as quickly as .842s? Also, aren't you better off trying to get your desired lift with lifter rise rather than rocker ratio?

i wish i could show you a Cam Lobe Pic of a NHRA Stocker Chrysler Street Hemi Hyd , now Solid Flat Lifter Cam Lobes ,
i think you would be shocked !

i know you would say "i don't see how that could work ! "

[RevTheory]

Me thinks the .810 wheel reduces the pressure angle on a given lobe and the larger body resists distortion so it's less likely to bleed out around the plunger as quickly compared to a .842 lifter body.

[Stan Weiss]

Do larger hyd/roller lifter bodies, say .903, give up the ghost as quickly as .842s? Also, aren't you better off trying to get your desired lift with lifter rise rather than rocker ratio?

i wish i could show you a Cam Lobe Pic of a NHRA Stocker Chrysler Street Hemi Hyd , now Solid Flat Lifter Cam Lobes ,
i think you would be shocked !

i know you would say "i don't see how that could work ! "

Larry,
Back in the 60's Pontiac developed a new cam with more duration. From what I understand there was some kind of lift rule and this lobe had to much lift. I don't have a picture of a cam / lobe, but it looks like someone just removed the top of the lobe. This is a rough idea of what the lift curve looked like.

Stan

ab-pont-744c-lift2.gif

[MadBill]

A lobe like that would surely see more dynamic than measured lift, whether it was actually designed to loft or not!

[rustbucket79]

"Stocker" lobes look pretty square given the big duration and "blueprint" lift?

[67RS502]

"Stocker" lobes look pretty square given the big duration and "blueprint" lift?

I would imagine so, but would they live on the street?
So either way were dealing with a lobe that needs to live on the street, with a HR or SR lifter.

[rustbucket79]

A "stock" cam has a single purpose, to be part of a combo designed to run the quarter mile as quick as possible while fitting a lift specification. It would be miserable to try and street drive and is as out of place in a street engine as a .900" lift solid roller cam.