Valve Springs for a 340 J Heads

[Waco Demon]

I am geting a set of J Heads rebuilt . I'm get the parts all to geather for the shop to do the valve job . I need to know what springs to get non rotator or rotator . I am building a 340 , I am going to put a Edelbrock Performer Plus cam . Which Edelbrock spring should I order ?
Harold Dobbins

 

[rumblefish360]

Harold,

Theres only 2 edelbrock springs, performer cam and RPM cam.

The rotor issue.... what you need to get is just plain old stock retainers and proper locks to use with the valve.

IMO, FWIW, I'd take that Edel. Performer cam and use it to beat up a .... a ... a .... well throw it away.

I'd look at a Comp Cam, Huges or a Lunati.

What are you building and what are the specs of it all, gear ratio, tranny, engine size, expected performance level sought. (What you want out of the car.)

 

[Waco Demon]

Rumblefish360 I'm building it for a 1972 Demon street rod .
Harold Dobbins

 

[rumblefish360]

Great! What axle ratio do you have or will have?

What tranny is in the car or will end up in the car?

Is there a "Time" you want to run at the track or intend it to run like?

 

[siuauto]

Rumblefish, why don't you like the Edlebrock performer cam? I was going to put a vodoo in but I choose the performer? Did I make a mistake. does it suck because of Performance or is the adjustable valvetrain? I am curious to hear from you

 

[340 8BBL]

the edlelbrock cam is an old design,and its only [email protected] stock 340 cam has more lift and duration.the eddy would be a good rv cam for a 318 in a truck,but its advertised power band of idle to 5500 is a stretch at best.im running a schnieder cam in my 340 with 220/230@50 on the street.the more modern grinds like rumble suggested will make alot more power.but there are other factors to consider like idle quality,rpm range,your compression and gearing play a role as well.

 

[siuauto]

Sorry I have a performer rpm cam? What is your take on that cam. I have the same manifold a 650 demon carb 4 speed with a 8 3/4 391 rearend. The also has headers a MSD dist and box. I have roller rockers and Sure Seat springs. I would like to hear your thoughts on my selection oh the engine is a 360 I don't know the compression because I have not had the engine apart.

 

[rumblefish360]

Rumblefish, why don't you like the Edlebrock performer cam? I was going to put a vodoo in but I choose the performer? Did I make a mistake. does it suck because of Performance or is the adjustable valvetrain? I am curious to hear from you

Sorry I have a performer rpm cam? What is your take on that cam. I have the same manifold a 650 demon carb 4 speed with a 8 3/4 391 rearend. The also has headers a MSD dist and box. I have roller rockers and Sure Seat springs. I would like to hear your thoughts on my selection oh the engine is a 360 I don't know the compression because I have not had the engine apart.

The cam is a (Very) slow rate of lift and ramp speed cam with more exhaust duration than needed for the heads they package togther as a "Matched set" and OH! Not to mention that the heads, as advertised flow very well in the higher lift ranges that the cam doesn't even think about taking advatnage of. WHY IS THAT?!?!??!

How cares!!!!!!!!!!!

At a min, I'd be looking at a Comp Cam and for surely entertaining a Voo-Doo / Huges engines cam.

Your set up sounds good. If your comp ratio is 10-1, your making 400+ hp.

The biggest issue on this forum and the opinions expressed by those here is choice. You and others take to much stock in certain items. While IMO, I'll use a different and better cam for your or my set up rather than what Edelbrock sells, the difference could be a good bit more power, but if your just cruiseing the street and/or minor strip runs, the real bottom line is if your happy with the way the car performs.

A Mistake? Opinions on cams and etc... are so wide and varied, the changes so small, hairs are split everyday on these choices. It's small potatos in the big picture. And that would be the grin on your face everytime you mash the go pedal.

Everyone has there opinion and a cam as well as other parts, but cams pull the most opinionated and most debated subject there is here and anywhere you talk about it.

Go on, start a thread. Title it, what cam to replace my RPM cam?

Watch that list grow big and fast.

 

[moper]

Siu - If you're happy with the results, don't sweat it. I am not a fan of the Edelbrock cams or lifters. But not because they don't run ok. Just that there are products that will make it run better for similar $$.

WACO - You need to match the springs to your camshaft. As I said, I'd be looking for a better camshaft but that's me. The std Performer cam can run any single w/damper spring. The Comp 901-16s are cheap and easy to find. Your 340 would not have had rotators, but if you got 360 heads (not Js, the later ones) you would have them and that's aretainer change, not a spring change.