Why? You can buy the engine cheap and boost to whatever you want. How long it lasts is another story. If he wants to buy a junkyard engine and a few spares, he probably could make it work for minimal down time. If he gets a gently used and well maintained engine, again, it could work. OTOH, a junkyard that says they have 3 and forgotten about the other 17 plus engines doesn't make me think they take good care of it or know the history.

The caveat is I probably could make it work if I bought it cheap enough and had it gone over by a reputable machine shop and refreshed. That or get lucky and stumble into that desirable motor that nobody knew was valuable and you got it for a bargain and it works forever. If there were 10000 tickets and I bought 9999, I'd still not win.

 

Actually, OEM parts are not that cheap, and are often produced with higher quality and tighter regulations than aftermarket parts.

I would much rather trust an engine full to the top with original parts.

 

Cheap depends on what you mean. If by cheap you mean I pay less at the counter today, that is a definition. If by cheap you mean it costs less today but nickel and dimes me to death tomorrow, well....

I wouldn't. Good parts are one thing. Put the best parts into a motor and it can still be a POS if the assembly isn't there. OEM is designed for one thing. Mass production.

 

Hypereutectic pistons and powder metal rods gonna make some big holes in your block at 600hp. Blocks and gasket w/o fire rings in a motor with boost not going to last very long. Your quite a dreamer with parts too.

 

So I am confused. Did you not get the memo? The OEM bottom end of the 5.3L Aluminum engine has recently gone 184mph in the 1/4 mile.

SO many have produced over 800 horsepower using the stock engine, there are reliability lists all over the web regarding these facts
https://ls1tech.com/forums/forced-in...lity-list.html

https://www.corvetteforum.com/forums...lity-list.html

http://www.ls1gto.com/forums/showthread.php?t=401429

 

You highlight everything I wanted to get across that is important- "assembly" is the critical component of both OEM and aftermarket rebuilds. "assembly" means you are able to correctly measure those "stronger than stock" aftermarket parts and install them.

Assembly is actually very difficult to achieve because FSM procedure no longer applies, and many aftermarket companies assume the "assembler" is going to be able to figure out how to modify their parts (such as connecting rods) from an unacceptable out-of-the-box condition.

And it almost never happens.

 

Yeah that list shows 7 of 38 came apart. That's nearly 20%. And that's only the ones that are honest. How many are garage queens that can't be driven and the owner is in denial trying to claim bragg'n rights? Yes a dreamer with a bent motor. And here's the link to the carnage: https://www.corvetteforum.com/forums...ottom-end.html

The new supercharged LT4 has forged pistons but you ain't gonna find one in the junkyard let alone for $500. It has a forged crank to. Chevy knows that's what's needed for a boosted engine or they wouldn't use it.

I give that " reliability list" a 20% credibility rating because I can read at least 20% of it is true.

 

You must consider a couple different perspectives for this to come together as a risk/reward scenario.
Most of the builds from the list are done cheaply with poor tuning and cheap parts. I am not advocating cheap parts or poor tuning. I am showing you that even with poor tuning and cheap parts, there still exists a "reliability list". The mere fact a list like that continues to propagate is a sign that the engine in question is worth a second look.


Ex. Do you think the stock engine that went 184mph in the 1/4 mile is going to last 100,000 miles?
There are some people who just want to break records, even if the engine only lasts 1 run.
From their perspective, it is cheaper to buy X stock engines and keep replacing those engines, than it is to build a proper engine in the first place. These guys are "racing themselves". Many of them have tried built engines with forged pistons first and failed, only to return to stock bottom ends as being "more reliable". I would suggest some research on this matter to help dismantle "forged fever". The hypereutectic piston's major weakness is its easy-to-break nature, one mistake can ruin it. ONE mistake. And yet so many of these engines with poor tuning and 8 cylinders persist for so many miles, it must be a very forgiving engine to tune.


Perspective 2:
For us "daily driver enthusiasts" it is far more useful to look in terms of miles vs output, rather than max power vs drag strip runs. I like to use "ten year statistics" or 100,000 miles (10k/year of driving) as a standard. Also, Supercharged engines should not be considered. The power they draw from the rotating kinetics of the engine is unaccounted for at the rear tires, but still count's in the making. In other words, a 600 horsepower supercharged engine is really a 680 horsepower turbocharged engine, but the supercharger draws 80 horsepower (or more) from the engine at that power level. That extra power makes all the difference to the bottom end staying together, and to the condition of the bearings in the engine. Strike those example from the list and we get something useful:


If the proper statistical analysis is performed against a 10year/standard w/ turbocharged, those engines with poor tuning and cheap parts producing between 500-600 horsepower that started with 100,000 miles have more than 98% probability to go another 100,000 miles.
In the 600-700 bracket, engines with poor tuning and cheap parts which started with 100,000 miles have 92% chance to go 100,000 miles.
We can't, or shouldn't, perform any analysis on engines which achieve higher than 700 horsepower because of the sporadic nature of results at that power level, which I attribute to poor tuning and cheap supporting parts still. The engines can't be blamed for these issues and that power level is unnecessary for the majority of budget daily drivers anyways.


This is the best probability of any engine ever made, that is available for less than $1000. I thought the same thing as you when I first encountered the idea, but time and results changed my mind. There are plenty of people not on that list, with 5.3L engines that I've personally tuned and seen myself, even with cheap parts (and good tuning) that are still going today, after a couple years of service at 600 and change. I came to the conclusion that if I could get one to last 50,000 miles @ 500 to the wheels i would be quite happy for those 3-4 years of daily driving. If it even goes half of that I will consider turning it up along the way to 600 and change. Since a next stock replacement is "sitting on the shelf" in case I make a mistake and need to go back to the 500 range ($1/horsepower for 5 years) the next day.

And believe it or not, the 2jz-gte 3.0L engine actually has a better regression, more mileage and higher power is possible. The only reason I chose the V8 instead was because the 2jz is three times the cost and more than twice as difficult to find spare engines for.

 

Let me know if I summarized this right. Fast, Cheap and Reliable. Pick any TWO. Cheap, being defined as the lowest cost out the door and not long term cost. I don't enjoy wrenching on my car. I enjoy the rapid acceleration so I will try to get a good engine. IIRC, LPE installed packages will come with a 3 yr 36K warranty. OTOH, I can simply buy 20 "cheap" $500 motors, blow it up and spend time wrenching the new one in like a battery replacement. IDK about you but if I enjoyed turning wrenches instead of driving, I might as well get a job that will pay me to do it. I'd rather do it once and pay more and have years of pleasure stomping on it till it breaks.

 

It used to be pick two. But it isn't anymore. Nissan and Toyota released a 2.0/3.0 in 1992 that will accept 80 horsepower/cylinder for 200,000 miles. It just took chevrolet ten years to figure out the tricks and now they have the same thing. The engine doesn't need to fail; you just needed to know how to tune them. I would still be using the Japanese versions if they were still in production, but both Nissan and Toyota moved on in 2002 to new idea/engine designs.

 

This keeps getting funnier.. Well yes there some or I can believe there are some people that will keep trashing junkyard motors. I actually met a couple of street racing buddies that raced the same Pontiac firebird with rebuilt motors from a local shop. They boasted the local shop continually provided cheap Pontiac cores. I can remember this because of the way they advanced the cam. They would use the non-adjustable timing set that came with the core motor and just advanced the crank gear one full tooth. When I counted the gear teeth that would have been something like 18 degrees IIRC.
Well as far as racing to trash the motor goes that's something that NASCAR does but with expensive, purpose built engines. In fact new rules limit the number of engines a NASCAR team can use in the same season. But I'm sure their investment is over $50,000 each motor.

But for the rest of us trying to save enough for retirement a cam change makes the most sense to begin to improve performance.

 

I don't know why you keep going to racing. I am talking about a daily driver here- the most reliable version of that. Everything I post is with respect to daily drivers. We just discussed that $500 engines can go 200,000 miles with 500-600 horsepower in a 98% confidence interval.

The same way $2500 per engine Nissan 2.0L and Toyota 3.0L can go 200,000 miles with factory cast piston turbo application @ 80horsepower/cylinder.

 

If you are looking to begin to improve performance on an L98, I sure as hell won't start with the cam. It would be the intakes and headers and tuning.

 

This sure got a long way from a cam choice did the poster ever get some useful information or just waste their time?

 

The tuner should be the one advising him since he is going to tune it if he wants to go that route.

 

While I don't necessarily agree it would have been a more useful response as post #2. The goals budget and engine builder choices that are within the limits of the electronics should decide on the cam. But the real limitations of the electronics work you into a box where best to worst is probably 20 hp maybe 30 on the outside. If you pick something in the middle you are +-15 hp. In the bigger picture not as big a deal as is being turned into. I would think freeing up intake and exhaust is a better start and much more to be had there. A ZZ4 with less compression a tiny bit more cam and the same heads is 350 hp. If it was me I would pull the heads have a good valve job done and spring / guide work done to allow for .550 lift. Put in the ZZ4 cam if I was willing to pull the whole front of engine apart though a new timing chain might help a bunch with a 25 year old car then get some off the shelf 1 3/4 headers even if short tube the big money part would be a new intake and an XT would be the winner there is I did not feel like fabing on up as it is what I do for a living anyway, EFI and induction and have for 35 years. Personally would consider the cam optional if willing to take a 25 hp hit from around 350 at the crank.

 

That makes totally nonsense. Why would you care if you have 400hp or 600hp just to drive to work and smoke the tires occasionally? 400hp will do that! If you're not going to race it what does 600hp get you that 400hp and some steep gearing already does. Your in full dreaming mode to swap in a LS turbo to drive it at street speeds. And a whole lot more dangerous when it overpowers the car and wraps it around a pole.

Nonsense, nonsense!

 

Why 400? Why do you even need to increase risk at 200 when 100 will do?

 

I am not sure what you are suggesting. The newer corvette will have over 700 horsepower, now you are saying that it is too much power and nobody should have them. Well that is your opinion I guess.
It's pretty easy to turn power down. Just put a bolt under the pedal...

 

Just for the compare,

A lot of time and effort can be spent, nickle and dime a motor for power. The same gains can be had with the twist of a dial on the console- or by driving below sea level. The risk is reduced because now the engine can make peak VE or better at the same or lower RPM than with the cam swap.

In other words, 400 horses is 400 horses. Whether it comes from cam or boost is negligible, and the camshaft actually moving redline up makes it less desirable. Nickles and dimes are less desirable. Parts that stay with the engine are less desirable. If we put an expensive head/cam/intake on the engine then starve it for oil accidentally- I could lose all those parts, plus now anything I saved needs to be transferred to the new engine. I hope you can see why I, after performing 100+ cam swaps, prefer to use a stock engine instead.