I'm starting to collect parts for my new short block and one of the thing I'm looking for are budget lifters to go with the used 847 I just bought form a member. I'm only going to rev it to 6800 at the most and it a street car NOT a race car. Will the LS7 do what I'm asking?
Also can I reuse my CC Pro Mags Self alinging RR?

Thanks

 

The LS7s are capable of that, but then again so are the originals.

The LS7s are a cheap replacement so everyone seems to say you "have to have them" but in reality they have not been shown to be any better than what came stock in your car.

It amazes me how people "save" money buying mediocre parts and then waste it on unnecessary parts all in the same build.

If your signature is accurate I would reuse the 503 over the 847 and put the savings towards a bigger TB, suspension work.

 

Sig is accurate except i also have KYB AGX's on all four corners, LS1 front breaks, and all the other bolt on's. The stock short block didn't like the 150 shot of nitrous, it dident kill it but it smokes a little when i shove it to the floor. The new short bock(355) has the stock crank I beam rods a forged pistons for the nitrous. I like the 503 but I have to try the 847 and see what it will make... I read all kinds a bad thing about the 503 but it makes good power, but I want more...LOL

 

If you want a handful more, use the 847. If you want 10-15 more, go with a custom grind.

 

This is what I mean by I have to try. I'm sure a custom cam is great and I've read that they make better power, but I've also read that they are "OK". And even seen used ones for sale on here. Why?

 

When a custom cam is matched to your heads and that setup is matched to what you intent the car to do, then people are happier than going off the shelf, generally speaking.

 

Not sure where you read that the 503 wasn't all that good because that certainly is not the case. The 503 has had tremendous success, particularly over the past 3 or 4 years.

Just because a cam is for sale doesn't mean it's junk... And even if it did mean it was junk (which I suppose you think it does), I have seen FAR MORE off-the-shelf grinds than custom grinds for sale. People change setups for different reasons...it's just how it works. If I sold my ET streets for drag radials, does that mean the ET streets were junk?

Why do you feel like you have to try the 847? Dozens upon dozens of people have used the 847 and many have actually switched to something smaller and made MORE power. The research has already been done for you.

I've been around these cars for quite some time now (11 years, not as long as some other members though who will agree with me) and have seen the rapid progressive movement from off-the-shelf to custom grinds over the years and the average performance increase as a result. Cars are going faster and faster with surprisingly smaller camshafts. Up until about 5 years ago, the 847 and the 306 were the bees knees for LT1s. Those days are long gone.

Since you have ported heads, the potential to make more serious power is there, where a custom grind will deliver more positive results, not just in performance but also drivability (since you say this is mostly a street car). Had you had a cookie-cutter combo (say, stock heads) you don't stand much to gain by using a custom grind and an off-the-shelf grind (503 or equivalent) would suit you just fine, but for the marginal extra cost of having a custom grind spec'd you will be much happier.

One last thing...if you're going to be spinning your bottom end close to the 7,000rpm mark, you should definitely ditch those SA rockers for a NSA setup with guideplates and chromoly pushrods. Trusting self-aligning rockers at those RPMs is a bit risky, IMO.

I suppose the final thing is, it's your car. If you think the 847 will make you happy then go for it. But from what I have gathered over the years is that there are much better choices out there. Hopefully some other members will chime in with their experiences as well.

Good luck either way!

 

I guess that i should be clearer. Not bad thing about the 503, just not enought power. I'v enjoyed this combo for 2 years and now it time for something new. I've read everything I can find on the 847 and yes its not for everyone, It really works poorley in a stock head car, and thats what most people who complaine about the have them in. That said I got a Wicked deal on one used with only 4k on it and not a mark that i can see from the pics. I need to build the sort block anyway and I'll try the cam in it. If I dont like it I'll swap it for a different one, maybe a custon grind.

I thank you for the answer on ths SA RR, I thought I should replace them.

Last night I might have been a little sharp with what i was saying, BUT I asked one question and got sh*t on for my cam choice!!! I have been working on Z28's for over 20 years. This is my first FI car, but my 4th Z28, that I've done ALL my own work to encluding engine rebuilds. I figure the manufactur's make all kinds of different parts to keep different people happy, and right now this combo is what I think will keep me happy.

 

Despite Dwayne's delivery, I completely agree with him about the 847. He "sh*t" on your cam choice because it's old antiquated camshaft technology. If you're okay with that, run with it.

I don't doubt your experience on working with cars, but that really doesn't mean much when new proven technology emerges. You said yourself you want more power, so I just felt inclined that the BEST way to maximize your money is with a custom grind. And just because a cam is used and cheap doesn't mean you should use it. You said if you don't like it you'll swap it out and use something else, but why not have one spec'd for exactly what you want so you don't spend the money (cam, new valve springs/hardware, tuning, etc.) twice?

For what it's worth, I have never seen anyone using an off-the-shelf camshaft (in a comparable vehicle) come even close to putting down the numbers and ETs I have with my 383 and a custom grind stroker cam. I got the numbers I wanted right the first time!

Sorry if it sounds like I'm pressing you hard to do it "my way," I'm just trying to provide relevant info.

 

Not a good combination.

 

Well it's official I'm OLD School at 42.... LOL. Half the fun(for me) is working on the car, trying something new for me. It's how I relax on the weekends when it -20 and snowing.
When the 3 kids are gone and I have some real money to spend I will build a killer motor like your, and I'll be sure to talk to all the experts about what I should do. Untill then I'm going to have fun with what i can afford to do, and the extra $200 I dont have to spent on a custom cam lets me buy a set of PAC 918 valve springs that will handle any cam I through at it later.My time is FREE but a custom cam is expensive. Thanks for your input i appricate the info and the time you put into your post.

 

Thats what I thought.

So can i use the SA RR with guide plates and hardened PR.

 

No it will bind if you run plates with sa rockers. Having said that there is nothing really wrong with sa rockers as long as valve control is up to par. In fact to a point its actually more stable. There is however some trade off for durability.

Don't worry about the 847 and its 'old' technology. It works plenty well enough. In a h/c car it will completely destroy the 503 past peak tq if the heads are up to it.

I for one do not agree with all the things being done to make 'better' cams and the idea that certain people are just able to match up THE cam for your car. For all the harping people do on custom grinds being better, I have yet to see anyone back to back a bunch of them for the lt1 shelf, custom, or otherwise. The big thing missing from a lot of ads is validating the results before it gets to the customer... oops. Where are the engine dyno sheets where you did a-b-a testing, and exactly how many hours do you have on these hardware sets to prove they are durable?

Then again i'm just a dumb engineer who does engine development for a living, so maybe i'm just being overly critical.

 

Cams are great examples of TINSTAAFL. The advantage of a properly specced "custom" cam is that the compromises of the particular design are the ones YOU are willing to trade in exchange for something you want more. It doesn't always work out and it costs a few bucks more to have someone knowledgeable spec the cam out. No way would I fault anyone for getting an off the shelf grind - most of them work very well. But if you are very particular about getting the most out of your particular combo, a "custom" is the way to go, IMHO.

As far as the two cams being discussed here, they are quite different. The 847 is a bigger cam and gives up low end and mid range for top end power compared to the 503. Which will work better for the OP? Not enough info about his car and his preferences to tell. For most people, I bet they would prefer the 503 in a street car unless it had gears and a converter if it's an auto.

Rich

 

Finally somone that doesent think just because it's written on a forum it's true! Thanks for the insite into a normal rebuild that's not going to break the bank.

I'm really going to stir things up by using the stock crank, a set of scat rods and forged Speed Pro pistons, ballance it, and reve the sh*t out of it, to get peak power out of the 847. I'm also going to use my stock Opti a Lt4 extreme duty timing set, LS7 lifters, SA CC Pro Mags, Pac 918 springs shimmed properly and measured push rods. All the stuff in my sig. And give it 150 shot when ever i feel someone's getting to close. I've done ALOT worse to a regular SBC and they never flew apart..... In fact this will be my first set of after market rods to beat on.