Valve springs

[Rdchallenger]

I'm looking into different springs and I'm wondering if Comps 942-16 springs will work on a stock 340 head without any machine work needing done?
I see where people have mentioned the 901-16 springs not needing any machine work but unfortunately they do not provide enough lift for the Lunati cam I am leaning towards.

I'm honestly between going with the Lunati Voodoo 262/268 or the Voodoo 268/276.

I will be using 273 adjustable rockers as well as the Hughes performance lifters.

I know the 262/268 would be better since I am not using headers (hp manifolds) but the 268/276 I feel would be better with my gearing and the 2500 TC that is coming.

Thanks in advance!

[Chryco Psycho]

I can't help with the springs , I try not to use Comp stuff .
Sometimes less is more with the cam too often a bigger cam is just no fun , if you are running in the mid range of a smaller cam often the response & power can be better in the mid range if you spend most of the time in that rpm range anyway .

[chargerdon]

In my 360LA stroked to 408, with headers and a 9.75 compression ratio, im running with Lunati 10200703 cam 271/279 advertised.   I also am using Lunati dual springs and hydraulic lifters.    I love it !!   The idle is a little lumpy which can get a little annoying, but, it draws attention so i love that as well and throttle response is fantastic with my Edlebrock 600 cfm carb.   

I installed the 518 overdrive transmission and even in 3rd gear it will pull strong from 1500 rpm up...my TC is a rebuilt one with locking feature from Torco  that its stall is about 2400.    With 3.23 suregrip it will melt the tires from a dead stop if i floor it too early, in fact cant floor it until doing at least 10-15 mph depending on road surface.   

Hope this helps... 

[DeathProofCuda]

I'm looking into different springs and I'm wondering if Comps 942-16 springs will work on a stock 340 head without any machine work needing done?
I see where people have mentioned the 901-16 springs not needing any machine work but unfortunately they do not provide enough lift for the Lunati cam I am leaning towards.

I'm honestly between going with the Lunati Voodoo 262/268 or the Voodoo 268/276.

I will be using 273 adjustable rockers as well as the Hughes performance lifters.

I know the 262/268 would be better since I am not using headers (hp manifolds) but the 268/276 I feel would be better with my gearing and the 2500 TC that is coming.

Thanks in advance!

Curious, if you are planning to use a Lunati cam, why not also used the recommended Lunati valve springs?

Also, if you feel like your build is sitting in between the ideal situation for those two Lunati cams, you might want to consider going with a custom grind.  It's been a few years, but I had a cam custom spec'd by Dwayne Porter of Porting Racing Heads.  The cam was ground by Comp Cams and was nitrided to be harder than their off the shelf cams.  I don't remember exactly what I paid, but it wasn't a whole lot more than buying a cam off the shelf, maybe $150 more, including the nitriding process.  I considered it a drop in the bucket compared to the rest of my build costs.  Dwayne can spec out the sweet spot for a hopped up build that is still using factory manifolds, which is typically something you can't find in an off the shelf cam. 

[Rdchallenger]

In my 360LA stroked to 408, with headers and a 9.75 compression ratio, im running with Lunati 10200703 cam 271/279 advertised.   I also am using Lunati dual springs and hydraulic lifters.    I love it !!   The idle is a little lumpy which can get a little annoying, but, it draws attention so i love that as well and throttle response is fantastic with my Edlebrock 600 cfm carb.   

I installed the 518 overdrive transmission and even in 3rd gear it will pull strong from 1500 rpm up...my TC is a rebuilt one with locking feature from Torco  that its stall is about 2400.    With 3.23 suregrip it will melt the tires from a dead stop if i floor it too early, in fact cant floor it until doing at least 10-15 mph depending on road surface.   

Hope this helps...

It does, Thank you! Honestly I enjoy a rougher idle. The 703 has the same LSA as the Comp Xtreme Energy cam I was using (110) which really has a sweet idle and pulled me towards it.

[Rdchallenger]

I'm looking into different springs and I'm wondering if Comps 942-16 springs will work on a stock 340 head without any machine work needing done?
I see where people have mentioned the 901-16 springs not needing any machine work but unfortunately they do not provide enough lift for the Lunati cam I am leaning towards.

I'm honestly between going with the Lunati Voodoo 262/268 or the Voodoo 268/276.

I will be using 273 adjustable rockers as well as the Hughes performance lifters.

I know the 262/268 would be better since I am not using headers (hp manifolds) but the 268/276 I feel would be better with my gearing and the 2500 TC that is coming.

Thanks in advance!

Curious, if you are planning to use a Lunati cam, why not also used the recommended Lunati valve springs?

Also, if you feel like your build is sitting in between the ideal situation for those two Lunati cams, you might want to consider going with a custom grind.  It's been a few years, but I had a cam custom spec'd by Dwayne Porter of Porting Racing Heads.  The cam was ground by Comp Cams and was nitrided to be harder than their off the shelf cams.  I don't remember exactly what I paid, but it wasn't a whole lot more than buying a cam off the shelf, maybe $150 more, including the nitriding process.  I considered it a drop in the bucket compared to the rest of my build costs.  Dwayne can spec out the sweet spot for a hopped up build that is still using factory manifolds, which is typically something you can't find in an off the shelf cam. 

Thank you for the info!

The reason I'm not wanting to go with the springs that come in their set is with them being dual it would require me to have the heads machined to properly fit them. The singles I could still get away using without any work needing to be done to the heads. Well the 901-26 I for sure know. Not sure if I could with the 911-16.

A custom grind would be ideal with this engine since I'm between the two on a sweet spot. The biggest problem with that though is I bought this motor already assembled about 5 years ago and the file that I had saved with exact specs is long gone. The only real info of it is that it was built to 1968 specs of a 340 factory complete with never being bored as well as using '68 internals. Which unfortunately doesn't help when trying to give info to a cam builder without really digging into the engine.

[DeathProofCuda]

I'm looking into different springs and I'm wondering if Comps 942-16 springs will work on a stock 340 head without any machine work needing done?
I see where people have mentioned the 901-16 springs not needing any machine work but unfortunately they do not provide enough lift for the Lunati cam I am leaning towards.

I'm honestly between going with the Lunati Voodoo 262/268 or the Voodoo 268/276.

I will be using 273 adjustable rockers as well as the Hughes performance lifters.

I know the 262/268 would be better since I am not using headers (hp manifolds) but the 268/276 I feel would be better with my gearing and the 2500 TC that is coming.

Thanks in advance!

Curious, if you are planning to use a Lunati cam, why not also used the recommended Lunati valve springs?

Also, if you feel like your build is sitting in between the ideal situation for those two Lunati cams, you might want to consider going with a custom grind.  It's been a few years, but I had a cam custom spec'd by Dwayne Porter of Porting Racing Heads.  The cam was ground by Comp Cams and was nitrided to be harder than their off the shelf cams.  I don't remember exactly what I paid, but it wasn't a whole lot more than buying a cam off the shelf, maybe $150 more, including the nitriding process.  I considered it a drop in the bucket compared to the rest of my build costs.  Dwayne can spec out the sweet spot for a hopped up build that is still using factory manifolds, which is typically something you can't find in an off the shelf cam. 

Thank you for the info!

The reason I'm not wanting to go with the springs that come in their set is with them being dual it would require me to have the heads machined to properly fit them. The singles I could still get away using without any work needing to be done to the heads. Well the 901-26 I for sure know. Not sure if I could with the 911-16.

A custom grind would be ideal with this engine since I'm between the two on a sweet spot. The biggest problem with that though is I bought this motor already assembled about 5 years ago and the file that I had saved with exact specs is long gone. The only real info of it is that it was built to 1968 specs of a 340 factory complete with never being bored as well as using '68 internals. Which unfortunately doesn't help when trying to give info to a cam builder without really digging into the engine.

That all makes sense. 

[DeathProofCuda]

In my 360LA stroked to 408, with headers and a 9.75 compression ratio, im running with Lunati 10200703 cam 271/279 advertised.   I also am using Lunati dual springs and hydraulic lifters.    I love it !!   The idle is a little lumpy which can get a little annoying, but, it draws attention so i love that as well and throttle response is fantastic with my Edlebrock 600 cfm carb.   

I installed the 518 overdrive transmission and even in 3rd gear it will pull strong from 1500 rpm up...my TC is a rebuilt one with locking feature from Torco  that its stall is about 2400.    With 3.23 suregrip it will melt the tires from a dead stop if i floor it too early, in fact cant floor it until doing at least 10-15 mph depending on road surface.   

Hope this helps...

It does, Thank you! Honestly I enjoy a rougher idle. The 703 has the same LSA as the Comp Xtreme Energy cam I was using (110) which really has a sweet idle and pulled me towards it.

Not going to claim to be a cam expert, but my understanding is that the 110 LSA of those cams is exactly what makes them the wrong cams for an engine running stock exhaust manifolds.  You are correct that the 110 LSA will give it a nice lumpy idle, but for optimum performance with manifolds you'll generally want to be running a cam with an LSA in the 112 to 114 range.

Are you totally against running headers on this car?

[Rdchallenger]

In my 360LA stroked to 408, with headers and a 9.75 compression ratio, im running with Lunati 10200703 cam 271/279 advertised.   I also am using Lunati dual springs and hydraulic lifters.    I love it !!   The idle is a little lumpy which can get a little annoying, but, it draws attention so i love that as well and throttle response is fantastic with my Edlebrock 600 cfm carb.   

I installed the 518 overdrive transmission and even in 3rd gear it will pull strong from 1500 rpm up...my TC is a rebuilt one with locking feature from Torco  that its stall is about 2400.    With 3.23 suregrip it will melt the tires from a dead stop if i floor it too early, in fact cant floor it until doing at least 10-15 mph depending on road surface.   

Hope this helps...

It does, Thank you! Honestly I enjoy a rougher idle. The 703 has the same LSA as the Comp Xtreme Energy cam I was using (110) which really has a sweet idle and pulled me towards it.

Not going to claim to be a cam expert, but my understanding is that the 110 LSA of those cams is exactly what makes them the wrong cams for an engine running stock exhaust manifolds.  You are correct that the 110 LSA will give it a nice lumpy idle, but for optimum performance with manifolds you'll generally want to be running a cam with an LSA in the 112 to 114 range.

Are you totally against running headers on this car?

Oh without a doubt, no desire really of going to headers finding these manifolds at the time was tough hahaha.

The more research I've been doing the more it comes up that the 702 would be the better of the two so I wouldn't risk overcamming it. Especially with it just being a street car with slim to no chance of track time.

[Rdchallenger]

The thing that makes me go "hmmm" about stepping up on the cam size is the description I have on the lifters I purchased from Hughes.

"The even bleed down rates will also produce a smoother running engine, with more vacuum at lower RPMs. With these lifters, you can step up 1 cam size and not lose any low end or vacuum."

Of course I could call Hughes and ask but I've heard he can be quite the @$$ and I deal enough with that working in a prison hahaha.

[DeathProofCuda]

I just looked at the specs on my custom cam again.  It basically sits right in between the two Lunati Voodoo cams that you are looking at.  Duration is closer to the 268/276 cam, lift is slightly less, but it uses a 113 LCA since I am running manifolds.  383 4-speed with 3.91 gears.