[TedRamAirII]

All the talk of Flat Tappet Cams had me worried. Is there a hydraulic roller that would be a good replacement or upgrade that would be suitable? Not looking to go wild. 400, stock RAII heads 70cc 10.5 CR

[Cliff R]

Plenty of good choices out there with similar specs. Most HR profiles will have larger lobes and considerably more lift, so typically you'll need more running room with the springs.

A very good choice is the Stumpuller cam from Dave at SD:

"In a recent dyno test this cam installed in a 464ci engine with 9.5 to 1 compression, a set of our 250-260cfm CNC ported #11 cast iron heads, CNC ported cast iron Q-jet intake and a prepped Q-jet carb made 503hp and 575+ lb/ft of torque on 91 octane."

Pretty stout numbers for a relatively "low" compression 455 build with iron heads on it..........Cliff

[Half-Inch Stud]

I too want a way-forward into a Street Roller valvetrain. The Flat HYD is fine in primary MTR but Spare MTR awaits thrifty decisions.

Have a Roller cam, but the 0.442" lobes hs me sticker-scared & Reliability-fearful to buy HYD RollinLifters & Springs for my Street RAIIs...

What is Stump-Puller lobe lift?
Are the ~$150 Pontiac V8 Roller Lifter sets on ebay of ANY use for Street?
Are Street Rolleer Springs affordable compared to the 0.440" lobe Roller Cams using Springs Pac 1243-16 or Trick flow 16943-16 ( both $293 at Summit)

[cnc]

Stump puller specs in sig...version #1 I think there is a sec or maybe even a third version....
Here is my Cam Card....

[tooski]

Originally Posted by Half-Inch Stud

What is Stump-Puller lobe lift?

Intake .3770, exhaust .3800

[ponyakr]

Looks like the Stump Puller has nearly .600 lift, with 1.52 rockers.

http://www.sdperformance.com/viewPro...productID=1815


This one has much less lift, which should be plenty for a street driven car & might work just fine with lighter springs.

https://butlerperformance.com/i-2936...tegory:1272239

CC recommends their 995-16 springs for their XR series HR cams, which have up to .540 lift, with 1.5 rockers. They're $98 on Ebay.

http://www.compcams.com/catalog/204_205.html

https://www.ebay.com/itm/132843063249

Butler also shows the CC 985-16 & 987-16 springs which might work for some low lift Pontiac HR cams. These are also reasonably priced, from lots of vendors.

https://butlerperformance.com/i-2445...tegory:1234802

https://butlerperformance.com/i-2445...tegory:1234802

[Cliff R]

Coincidentally we just finished a carb for a 455 built and dyno'd at Butler with the cam listed above. It made good power on the dyno, smooth idle, and I'm sure it will have excellent street manners.

It wasn't all that high for compression, pretty sure it used 455 HO heads but can't remember the flow numbers or the actual dyno numbers, but over 1hp/CID and around 540ft lbs torque. I've used the same cam here in a 455 Super Duty build and it cranked out 457hp/529tq and idled very smooth clear down to 600rpms. Also take note that Butler has it ground on a 114LSA. I've done it on 112 and 114LSA for 455's we've done here.

We also use a larger 230/242 @ .050" cam on a 112LSA with .361" lobes which makes right at 500-515hp in a 455 build with unported KRE aluminum "D" port heads..........Cliff

[Steve C.]

Comp just regurgitate's the use of the 995 springs for their hydraulic roller cams. Do a search on the subject of spring pressure with a hydraulic roller cam.

One of many....

http://forums.maxperformanceinc.com/...t=Pontiac+Dude


Quote from a thread about spring pressure by Cliff Ruggles 3/2011:

"Dave at SD also mentioned in his email, that he went to the this stiffer spring deal over using Comp 995 springs, as they used to use them on iron heads for HR set-ups. After observing some valve float "issues" on the dyno, he just kept upping spring pressures to get it under control. He considers 140lbs on the seat, and 350lbs over the nose the absolute minimum for a HR set-up."

"Keep in mind that most cam manufacturers tend to recommend springs that are on the minimum side of pressure, to too weak. If you add 15-20 lbs for their suggested pressure you'll be pretty close to where you need to be. They tend to base their spring recommendations off of Chevy engines, I think. They don't take into consideration things like valve seat angle, and valve weight, etc."
Paul Carter
gtofreek


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[Steve C.]

In addition of lobes 3111B & 3122B as mentioned in post #4 above Dave has also used lobes 3194 & 3196 for the "revised " Stump Puller.

Grind# P8 31294 / 3196 HR112+5

281 / 287 at .006"
230 / 236 at .050"
.3890" / .3910" lobe lift
112 LSA

And note 5 degrees advanced. And on occasions he orders it with "B" roller cam suffix codes after the lobe number.

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[Cliff R]

Comp's 3315B and 3316B lobes are quite a bit smaller at .340 and .347" respectively. I attached the cam card of one the one that we used on the 455 Super Duty build and the dyno sheet.......Cliff

[gtofreek]

I put this cam in a 413[+.065" 400] and it made 478 HP and over 500 Ft. Lbs. of torque with #670 D-Ports ported to 260/206, with an Iron intake, Q-jet, and points distributor. It made 415 Ft. Lbs., at 1500 RPM. Made 500 Ft. Lbs. @ 2800 RPM. It is 231/239 @ .050".

http://www.lunatipower.com/Product.aspx?id=3210&gid=289

With an RPM intake[unported] it made over 500 Ft. Lbs. from 2800-4200 RPM, and peaked at 525 Ft. Lbs. It made over 500 HP with a single plane intake and a Holley carb.

[Steve C.]

As eluded to here by Cliff and ponyakr a stock installed height could put a damper on valve spring selection.

Could be related....

https://www.hotrod.com/articles/how-...rance-is-safe/


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[Jay S]

Bullet has a profile that looks like it would come close to mimicking a ram 4 cam

HR301/313 Int. 301 seat, 234 at .050. .313 lift
HR 310/313 Exh. 310 seat, 242 at .050. .313 lift


This is from memory, I might be a couple numbers off:
RA 4. At .004 rating 304/315. @ .006 292/303
231/240 @.050, 313/.313. 113.5 lsa, 113 Icl.

Probably could tighten the lsa up a little on the roller and make it sound like an 041, maybe 112???? A lot less efficient cam than most modern hyd grinds. But with 10.5 compression, most of the rollers would want race gas, this would be a drop in an go replacement, and would tolerate compression similarly to the 041. More than likely about the same performance as a 041. Jay

[ponjohn]

Is the stump puller really that similar to the RAIV, thought RAIV was bigger?

[Steve C.]

Compare the numbers....

Pontiac 9794041 (RAIV)
308 / 320
231 / 240
.4700"/.4700"
114


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