will i need new springs with this cam?

[Jaysam]

Hey Guys ,

Im trying to get more power (on the cheap) out of my bone stock '74 Satellite w/318 no a/c, no p/s, no p/b
and a manual 3spd on the column. The car has 69,XXXmi and i recently bought a 8 3/4 rear for it to start my upgrades. Im looking at headers and an engine combo kit from summit
summitracing.com/parts/cmb-03-0162/overview/make/plymouth/model/satellite/year/1974
It has a Holley Street Avenger 670 cfm, Weiand #8022 Stealth Dual Plane Intake, and a Lunati Voodoo Cam and Lifters, Hydraulic Flat Tappet, Duration 268/276, Lift .494/.513. I wasn't looking at any head work
(like i said on the cheap). I've never done any internal engine stuff, just routine bolt on stuff so the cam thing is new to me. Since the front of the motor will be apart i'll replace the timing chain with a double roller and replace the water pump. I guess im wondering with this cam if i'll need to change out my stock push rods, valve springs, and rocker arms? if i need to change all that i may just go with a different cam so i can keep the stock valve train, again (on the cheap) just trying to get the best bang for my buck, dont wanna put a ton of $$$ into the 318 right now, just wanna make it more fun to drive with parts that are easily accessible. Thanks again guys for any info on my simple ??'s.
Thanks, Jason

 

[RustyRatRod]

Absolutely. You will need the matching springs for that one. Unless you plan on raising compression a LOT, that's way too much cam. But it'll sound good. lol

 

[99ss]

What about pushrods? Dont those need to be swapped as well? Correct length and hardened?

 

[rsd859]

If you email summit expert advise guys and tell them what your doing, they are very helpful. Keep in mind they may not tell you what you want to hear, but it will be the truth.

 

[RustyRatRod]

Oh yeah. Ask the guys who you're BUYIN stuff from what to run. Genius.

And no, there's no need to change pushrods.

 

[99ss]

And no, there's no need to change pushrods.

Really? With the LSx platform you need hardened pushrods due to the increased spring pressures and the cam basecircle usually changes the pushrod length

 

[WP29440SE]

Oh yeah. Ask the guys who you're BUYIN stuff from what to run. Genius.

And no, there's no need to change pushrods.

xs2. they tried to sell me all kinds of crap i didnt need . good guys , but they will tell you anything to sell you stuff.

 

[rsd859]

Let us know what you decide to do. Take pics before you tear it apart, keep everything organized, clean, and you should be alright. And this is the most important, post pics for all to see!

 

[RustyRatRod]

Really? With the LSx platform you need hardened pushrods due to the increased spring pressures and the cam basecircle usually changes the pushrod length

THe spring pressure with mild hydraulics is the same or BARELY over stock. It's not the pressure that's the reason you need matching springs. It's the spring rate. Now, when you get into larger solids and rollers, then the pressure becomes more important.

 

[Jaysam]

ok thanks for the info guys, i guess i'll look for a different kit. So maybe thats to much carb and intake for the stock 318 also?

oh yea i'll definitely take pics and post, because i'm sure i'll be asking more ??'s

 

[99ss]

THe spring pressure with mild hydraulics is the same or BARELY over stock. It's not the pressure that's the reason you need matching springs. It's the spring rate. Now, when you get into larger solids and rollers, then the pressure becomes more important.

Well I understand about rates but I guess we use more agressive cams and so the PR's always get swapped out as well with our platform. Flex and correct length are the reasons. Most of the time guys go to a double spirng and over.600 lift on the cam. My cam is close to .700 lift but we use a massive single from PAC

 

[YY1]

The "small" summit cam (.450 lift) is .050 more than the factoey 318 cam, has better duration at .050 lift and specifically says you don't need to change out the stock springs. It's cheap, too.

If you're OK with changing the springs, the Comp XE256 or 262 might fit the bill, as well as the stock 340 grind, or any in the neigborhood, spec wise.

Considering the factory 318 cam is .399 lift, I'm guessing the .450 will be a noticeable improvement.

I definately wouldn't put a .513 lift cam in an 8:1 motor with 1.5" exhaust valves

 

[19polara64]

You could always ask the guys on here if they have spare parts laying around. I rarely buy new engine stuff, used works just fine and I get more bang for my buck. Headers are about the only thing that gets really worn out, but you can find lightly used sets.

 

[RustyRatRod]

The Summit cam is an excellent choice. Also, if you have more money to spend, the Hughes Whiplash cams are designed to use stock springs as well. If it was me, I'd do the Summit stab. YY1 made a great recommendation.

- - - Updated - - -

The Summit cam is an excellent choice. Also, if you have more money to spend, the Hughes Whiplash cams are designed to use stock springs as well. If it was me, I'd do the Summit stab. YY1 made a great recommendation.

 

[Meep-Meep]

Waaaaayyyyy too much cam and carb for the stock engine, and yes, using that cam will require new springs and possibly other head work like machining the top of the valve guide for proper retainer to guide clearance.

If you want to go faster on the cheap get a TQ carb and intake from a late model 360, a small 252 - 260 deg cam and a set of small tube headers and dual exhaust. With the tiny cam you may get away with the original springs or at least be able to pop on some new ones without removing the heads.

 

[Jaysam]

The "small" summit cam (.450 lift) is .050 more than the factoey 318 cam, has better duration at .050 lift and specifically says you don't need to change out the stock springs. It's cheap, too.

If you're OK with changing the springs, the Comp XE256 or 262 might fit the bill, as well as the stock 340 grind, or any in the neigborhood, spec wise.

Considering the factory 318 cam is .399 lift, I'm guessing the .450 will be a noticeable improvement.

I definately wouldn't put a .513 lift cam in an 8:1 motor with 1.5" exhaust valves

Thanks for the suggestion YY1, im gonna check it out and probably go with it

- - - Updated - - -

Waaaaayyyyy too much cam and carb for the stock engine, and yes, using that cam will require new springs and possibly other head work like machining the top of the valve guide for proper retainer to guide clearance.

If you want to go faster on the cheap get a TQ carb and intake from a late model 360, a small 252 - 260 deg cam and a set of small tube headers and dual exhaust. With the tiny cam you may get away with the original springs or at least be able to pop on some new ones without removing the heads.

Thanks MEEP, i may just look into that also, great suggestion

 

[rsd859]

How do you change the springs without dropping the valve in the cylinder? Not doubting that it can be done, Ive never tore apart a set of mopar heads.

 

[Jaysam]

The "small" summit cam (.450 lift) is .050 more than the factoey 318 cam, has better duration at .050 lift and specifically says you don't need to change out the stock springs. It's cheap, too.

If you're OK with changing the springs, the Comp XE256 or 262 might fit the bill, as well as the stock 340 grind, or any in the neigborhood, spec wise.

Considering the factory 318 cam is .399 lift, I'm guessing the .450 will be a noticeable improvement.

I definately wouldn't put a .513 lift cam in an 8:1 motor with 1.5" exhaust valves

YY1, do you happen to know the part# for the cam? I was looking on summits site and couldn't find it

 

[Cornpatch MO]

spark plug out, bring piston ready to move up in the cylinder to the compression stroke- feed small nylon rope into the sparkplug hole - raise piston till it stops, from compressing the rope against the closed valves. Now you can remove the springs without the valve dropping into the cylinder...................MO

 

[99ss]

spark plug out, bring piston ready to move up in the cylinder to the compression stroke- feed small nylon rope into the sparkplug hole - raise piston till it stops, from compressing the rope against the closed valves. Now you can remove the springs without the valve dropping into the cylinder...................MO

Yep or you can use a compressor w/adapter