Valve Spring durability

[akrt]

-continued-
I wanted to get my power squared away before suspension mods. I'm trying to keep my car untubbed. All the big block Chevy guys around here that are in the 9's run tubbed rearends. I know it's a difficult thing to do but I figured I'd try and if that doesn't do it I could mini tub my car and go from there...

 

[IQ52]

I've always viewed being a Mopar enthusiast as being part of a brotherhood. I can't imagine not helping my fellow Mopar enthusiasts. If there's something in my experience that can help someone else, I gladly and freely offer my advise. If I don't have an answer to a post, I don't respond. If you can't answer because you don't know the answer or that you do know the answer but won't share it because of how well you are paid makes no difference to me or anyone else who might benefit from said question. Better left unsaid, in my opinion. You're a Mopar guy. I'm a Mopar guy. I like you already. In responding to your questions: my motor is 588ci. Indy Legend heads. Currently stock ports that flow 350cfm. Once ported, will flow 440cfm. The current camshaft makes too much torque down low as I run 12.5" ET Street tires that spin like crazy. I'm looking to move my torque band higher up in the RPM range. I have super stock springs and a pinion snubber. Will install cal tracs at some point this summer. Also my power tends to level off after 5,500 rpms. I realize ladder bars may be in my future... I'm just trying to make my car faster.

Now this doesn't tell the whole story why your engine levels off at 5,500 rpm, but it might give you some insight as to the cam not being the problem. Input your cubic inch size and cylinder head airflow for an interesting result.
http://www.wallaceracing.com/max-rpm.php
http://www.wallaceracing.com/max-rpm.php

I don't think with 588ci you can't keep from spinning the tires like crazy without some suspension work. I used super stock springs with a pinion snubber and slicks and my 451 stroker would blow right through the tires.

 

[Challenger340]

Was the Engine Dyno'd on an Engine Dyno when built ?

That data would be invaluable in conjunction with the current Head Flow moving forward from here ?

What/Whose CNC program are you contemplating on the Legends ?
And,
* how much are they Billing for it ?
* claimed Air Flow @ L/D ?

 

[akrt]

IQ, interesting results..! I had planned on porting the heads years ago but couldn't afford it till now... As for my suspension, I have the cal-tracs ready to install. Im waiting to buy the single leaf springs that are recommended. I can fit a 12" tire and if I mini tub, approach 15"'s so I'm hoping to get my motor squared away. I didn't want to get my suspension done then start adding power...

 

[akrt]

Was not dyno'd...

 

[66Satellite47]

Figuring out the suspension will make the power usable. That much Hemi will take some figuring. Seems like the cam you had is plenty adequate. Doubt that a bigger cam will help the tires.

 

[69sunfireGTX]

I don't think he can hear you. He hasn't been on since May 2017

 

[66Satellite47]

I don't think he can hear you. He hasn't been on since May 2017

OOps. I didn't watch the dates on this post. Not sure why this showed up for me. Thanks

 

[dvw]

Big power on the street seldom hooks. Heck my wife's 360 9-1 Challenger will spin 275/60s from a roll. My 11.0 street car with 315 drag radials. Nothing but smoke from a dead hit. Same with my sons turbo 360 Savoy. All 3 are fine at the track. I wonder what ever happened?
Doug

 

[padam]

Big power on the street seldom hooks. Heck my wife's 360 9-1 Challenger will spin 275/60s from a roll. My 11.0 street car with 315 drag radials. Nothing but smoke from a dead hit. Same with my sons turbo 360 Savoy. All 3 are fine at the track. I wonder what ever happened?
Doug

This is why I wonder about people building 600 hp motors for a car that "will never go to the track."

 

[vintage chromoly]

This is why I wonder about people building 600 hp motors for a car that "will never go to the track."

Folks read about this kind of power on the net and in hotrod magazines.

without ever driving a car with power like that, they figure they need one.
For the most part, they haven’t a clue on what it takes to maintain that kind of an engine.

crazy.

This is why I wonder about people building 600 hp motors for a car that "will never go to the track."

 

[451Mopar]

I don't know Hemis, but having at least 2.00" install height is a good starting point.
I'm using the higher end PAC1326 valve springs, but I'm only 0.726" lift and 7,000 RPM with the Edelbrock Max Wedge Victors CNC ported by Hughes, so around 400 cfm

 

[dvw]

I don't know Hemis, but having at least 2.00" install height is a good starting point.
I'm using the higher end PAC1326 valve springs, but I'm only 0.726" lift and 7,000

I use less expensive Pac 1224. At 300 passes they haven't lost any pressure at all. [email protected]"/.800" lift in at 1.950". I've run this part # Pac spring in my car for 500 passes. No issues.
Doug

 

[Charger 770]

580 ci Hemi, Bullet 270/280 @.050, .750/680" lift. Ported Indy heads, Ti retainers, Stage V rockers, Isky bushed rollers, spray bar + thru the deck oiling.

Using PAC springs, (id have to dig out the part number) from memory they're installed at around 2.050" and have stabilised around 260 seat, 690 on the nose..

Been in there for 4 years of Street driving (not a daily, sometimes not a monthly either in Winter), had them off last Winter and they checked fine.

Key is oiling/temps, valve train mass, cam lobe aggressiveness/ramps factor and checking them.

This has worked for me so far.