Fredrik71

I'm currently rebuilding the engine for my 69 and going to replace the camshaft. The one that has been used until now is an Elgin 1070-P with the following spec:

Camshaft Type: Hydraulic Flat Tappet
RPM Range: 2000 to 4800 RPM
Intake Valve Lift: .527"
Exhaust Valve Lift: .553"
Advertised Intake Duration: 290°
Advertised Exhaust Duration: 292°
Intake Duration @ .050": 224°
Exhaust Duration @ .050": 234°
Lobe Separation: 114°
Intake Centerline: 110°

For me the RPM range looks quite narrow. But I like the rough idle. Maybe Comp Cams XE274H could be a good choice?

I'm using wiseco pistons PTS520A3, stock closed chamber heads (ported), stock intake, factory side pipes.

Sound when running the Elgin cam.

Sound

jackson

OP
Why do you want to change cam?

What does the motor do that you don't like?

How does the motor fail to meet your want/need?

Fredrik71

I'm changing cam because I'm doing a total rebuild of the engine. The cam and lifters shows some wear so I don't want to use them again.

Jebbysan

I think I would buy the same cam dude! Sounds great....but is it more power you are looking for? If so...I like this one for your L36: https://www.howardscams.com/hydrauli...0-howards-cams
The oval port heads will love this cam Just make sure you have significant clearance.... .550 is starting to push stock valvetrain specs.....it will sound even chunkier as it is ground on a 108LSA.

Jebby

0JUICED1

We have had some great success with BTR and GPI cams. The GPI stage 2 would be a great cam that isn't over the top but packs on some solid power. It makes solid torque gains and pulls hard to about 6700rpm. We get a lot of requests for the GPI stage 3 cam on the manual LS3 cars and its one of our favorites. Drives solid and the chop is amazing.

Sigforty

You do realize a LS cam will not work in the L36 big block chevy 427, right?

jackson

FWIW, current elgin cat specs for E-1070-P says RPM Range 2200 - 5400 ADV dur 290/292

Melling has virtually same cam (pn 22306) but their range speced at 2500 - 6000 ... it has slightly longer ADV dur 302/308

some companies figure ADV dur at different heights

Summit has a cam & lifter kit pn SUM-K1302 which seems all but same as 1070 ... $123

If you like cam, I also think you should get a new 1070, or one like it.

Vette5311

recheck specs. I believe LSA is 112 and 108 is intake C/L

leigh1322

Congratulations on keeping such a beautiful car and it's legacy going in Sweden! It must attract a LOT of attention over there.

And you are correct it is very risky to re-use a previously used hydraulic cam.

Depending on the level of local expertise you have available (in Sweden!) with High Performance Chevy engines you could consider switching to a hydraulic roller cam. It is more money, but the valvetrain/lifter setup is more complicated, requiring parts, money, experience and expertise. But it will make more power due to the cam design (more lift & faster ramps), and run on any available oil. A normal hydraulic cam is much easier/safer to install and setup, requiring less expertise, but requires very a specific break-in procedure or it will quickly fail. And it requires difficult to find zinc based oil or oil additives or it will fail slowly with time.

If you like the way that one sounds & runs, make sure your new cam is extremely close in all it's specifications. Those are very good specs for a street cam, and you are going to have a hard time finding one that makes it run "better", without giving something up, or making assembly more complicated. I'd just keep it, or it's twin, unless you want to dodge the oil issues.

cardo0

If you have headers along with side pipes I would think a single pattern cam would be better and I like the Comp Cams Magnum 230/230.

With stock exhaust manifolds then an asymmetric cam like the Comp Cams Xtreme 4x4 234/244 Hydraulic Flat Cam should be very similar to your present cam but make a little more power and handle a little better on the street also.

Always replace the valve springs with manufacture recommended springs when replacing the camshaft. Even more important with a high lift camshaft.

Hope this helps.

CosmicRay

I find myself with a similar issue, so I'll follow up with this thread.

I find my 74 454 has the 427/390 aluminum intake on it. I was getting prepared to go with something like an Edelbrock 2161, but since I have the L36 aluminum, I'm now not so sure i want to replace it. I'll work on determining that.

But, should I decide to stick with the L36, I find myself looking to get a new carb (which I need, no matter what)... and considering a new cam. My first question is:

1) Is there any way to determine which cam I already have in the car?

Without removing it, that is. Since the previous owner (whom I cannot reach) did put on an L36 intake, it's possible a non-stock cam was used. But before I know if it's worth going through the effort to swap it out, I'd really like to know what's in there, and what the specs are. Is there any way to tell?

And, the next question...

2) Similar to the above, I need to decide what cam, should I swap, is best for the L36 intake on a 454.

Mind you, I'm looking for mostly off-idle street performance, so I'm looking for the power band to be as low as possible. I don't know the normal band of the L36, but I'm interested in idle-5500 or so.

Opinions?

leigh1322

A degree wheel and a dial indicator. You can determine the lift and the .006 and .050 duration.Even the LC if you want.It would be time consuming and require pulling the pan, timing cover and intake.

Something like a CC XE274 runs nice on the street and is designed to make good street power with the probably low compression pistons. It's 230/236 duration. Anymore than that with low CR and it won't make good compression. Slightly less duration would be OK too, just not more. Like a XE268H. 224/230. That would make the power curve somewhat similar to a L46 350HP 350. Nice street curve. One has more idle rumble, second is smoother.

You can even work backwards from a compression test and get a "likely" compression ratio. It could always have been changed in 46 years.....

cv67

id use the elgin, had 0 luck with all XE cams even rollers went flat fast. When a cam is wanting to mimic a roller then put a roller in. Opinions may vary
Sure aint worth a few lbs of torque to rip the cam out in 1000 mi...or the whole engine.

leigh1322

The Melling cam mentioned 22306 has very mild lobes so is very easy on the valvetrain compared to the others. It has old school long ramps and is not a fast ramp cam. It has good idle chop, and can make 430-450 HP.

CosmicRay

Thanks for the reply. But just so we're clear, I'm dealing with a '74 454 BBC, with an L36 intake on it. The cam you mentioned was for a SBC, I see.

I might, at some point, just decide to not bother trying to determine my existing cam, but just replace it with one of my choice. However, not right now. Not only is it hot as hades (I'm in FL) but it's a huge project and I'd like to get started with some of the smaller items, like a new carb and ignition upgrade.

I like the idea of running a compression test. I think I know someone who has the equipment to do that.

leigh1322

A 74 454 came with as low as 8.2 CR. The cam has a huge effect on cranking compression. Without cam specs all you can get is a rough idea. But you still might be able to figure out if the pistons have been changed for ones with more compression.

CosmicRay

I'm not looking for super high compression, but 8.2 just seems a bit low.

What would I look for to determine that about the pistons?

derekderek

the engine is staying on the mounts and the heads are staying on the block for the time being? A cheap ebay borescope-endoscope will get a look at the piston tops. you can also go up through the oil drain plug if you just gotta know if it is 2 or 4 bolt block. you can also do home colonoscopies for all your friends...

CosmicRay

Yes, everything is staying on for the time being. Especially with the heat in FL nearing the temp of melting lead. I can do limited work in the garage with a portable AV but any serious work, on my friend's lift, will wait AT LEAST until October, when the temps start averaging under 85.

I actually have a borescope. While my friends have refused the discount colonoscopies, I found it handy to get my vette hood released. It's just a cheapie which connects to a tablet, but it allows me to look in places hidden to the naked eye. Still don't know how to recognize an aftermarket piston, though.

derekderek

not aftermarket or not. dome, flat or dish. and head casting number will get you the chamber size as long as somebody didn't do too much grinding on the chambers. i will post a couple pics later.