That may be a tall order if you are including heads and cam in the $4k budget. I just finished building the motor in my C5. I was able to reuse the block and the crank, and basically everything else was new (forged rods and pistons, PRC cnc ported 243 heads, Cam Motion cam, Struab trunnion kit, Melling oil pump, LS2 timing set, etc). I've got roughly $6500 in that portion of the build, and I did all of the work myself except for the machining of the short block (which I got a smoking deal on). Add on to that long tube headers and exhaust if you don't already have it. Add on an upgraded clutch if you have a manual trans. Add on to that if you want to upgrade the intake manifold. And add on to that the cost to have the car tuned when you are finished. You can easily be over $9k when all is said and done to do it right. And btw that won't get you to 550hp at the wheels, but would be a very reliable well built motor that can handle some abuse and make good power.

There are always cheaper ways to do things, but just go into it with your eyes open. Definitely calculate the costs before you dive in. (and decide if the rest of the car is in a condition to warrant that level of investment)

 

550 crank or rwhp? Agree, no way you will get 550 rwhp na for $4k. May not be possible to get 550 crank within that budget.

 

You can replace the camshaft, heads, springs, lifters, rods, oil pump, seals, clutch and maybe the rockers or intake manifold for under $4k. Touching the pistons, crank or block will put you over.

 

It's the little things that add up, especially on a high mileage motor. Somethings should be replaced because of the mileage, and others just because they are difficult to get to later.

Are you going to reuse a 172k mile water pump, probably not. New radiator hoses? Thermostat? How about plug wires? Are you going to add heat boot over the plug wires? Obviously new spark plugs. Are you going to reuse the OE harmonic balancer (known to separate and wobble), or are you going to a Powerbond or an ATI? Are you going to reuse all the drivebelt pulleys and tensioner? New belts? New O2 sensors? New oil pressure sensor? If you're adding big hp, then you'll be getting to the limit of the factory fuel injectors. Even if you don't need bigger injectors, sending the factory ones out to be cleaned and flow balanced would be smart if they have 172k miles on them. Are you going to keep the stock PCV setup, or swap to the 04+ LS6 valley cover/pcv? Are you going to add a catch can? You can easily spend several hundred dollars in new gaskets for the entire engine.

As mentioned, if you have a manual transmission, an upgraded clutch is going to necessary. If you have an automatic, you'll probably need a different TC to match the bigger cam.

If you're pulling the motor, then that's also a good time to pull the torque tube and inspect the couplers, etc. At that mileage, you will likely need to replace them.

I don't say all this to scare anyone but I do want to share accurate information. Sometimes engine building gets over simplified. I kept very details records of what I spent during my build... and honestly it's pretty depressing, haha. but I had counted the costs ahead of time and knew what I was getting into.

 

Not following the math here. New heads (high flowing with high compression) alone are more than half the budget. Depending on heads, you may need new rockers, stud kit etc. and do not forget injectors, fuel system upgrade, lifter trays .... Also, after all of this, need a tune, unless you can do it yourself. Not seeing a complete top end rebuild - turn key - bugs worked out for $4k. Maybe if you retain the stock intake, heads, as many of the other stock parts as possible and do a cam, headers, x-pipe. This can be done for under $4k. MAYBE (emphasis on maybe) stay under 4k with a new clutch as well, but it will be nowhere near 550 HP.

Been down this road before, cheaper to purchase a car already done and work out bugs that surface.

 

#truth

This is a lesson often learned the hard way (well at least I continue learning the hard way). Plus you only get a fraction of your investment back when you sell the car. And it's even worse on a high mileage car.

PS: I feel like we've been very discouraging... but please don't take it that way. Congrats on the new (to you) Corvette. It's a fun car, and I hope you're enjoying it!

 

Yes, agree, I am not trying to be discouraging either. Have fun with the car!

​​

 

$4,000 is not going to get you 550 reliable horsepower. Probably your cheapest option would be to try and find an LS3 take-out from a wrecked C6 and swap the cam. Even then I don't know if $4K would cut it. I just had my engine rebuilt and had the stock heads ported, no aftermarket heads. It makes 459 rear wheel hp, and overall I spent over 9 grand, although that includes about $2500 in labor. I'd think about saving for a while until you have the money to do it right. You'll be happier in the long run.

Remember, when it comes to hotrods, there's a saying: "Cheap, fast, reliable - pick any two."

 

 

The short block would probably be ok, but I'd want to know more about the shop that builds the engine; how many engines do they build, any customers you could follow up with, etc.
I looked back over their customer ratings and in over a year's time only saw customer feedback for one engine and that was a much more expensive engine than the short block shown in this listing. Could be a nice rebuild, but if it was me, I'd wonder why no feedback on the short block.
Not the end of the world but remember the iron block is going to be almost 50 pounds heavier than the LS1 block. For street driving you'll probably never notice it, but if you decided to road race it you probably would.
Also check to see if there are any good shops in your local area. Get to know the people there. Explain what you want to do to your car and why. Have them give you build ideas and pricing.
If the car is running ok for now, try to save as much as you can so that when you're ready to build it up you can give it the first class job you want. As several others have mentioned, you can spend a good part of your budget just on the replacement parts. They won't make your car go any faster, but you don't want to do much horsepower improvement in a 172k mile engine without replacing the balancer, oil pump, water pump, checking pulleys, replacing belts, gaskets, hoses, plug wires, plugs, etc, etc.
Please let us know what you do.

 

Texas Speed has head/cam (springs and rods included) combo's for $2-3k, depending on which one you choose and what other "while you're there" parts to replace, and a LS7 clutch kit for about $550. It's possible to replace what I mentioned before for less than $4k (labor not included). Getting to roughly 550hp on the other hand is not entirely possible to stay within that budget.

 

Ok, $2,500 for heads / cam package and $550 for clutch for $3,050. You also stated timing chain, oil pump and maybe rockers or intake. So, $300 for good chain and oil pump. That leaves you with $650. That takes away an intake option and makes it difficult to get a good set of rockers. And cannot forget a new set of injectors, ARP head bolts / studs, fuel system upgrade and a tune?? All that work and still wheezing through stock exhaust? Not going to happen under $4k. Just trying to get a clear picture of total cost to the OP.

 

The best way to do this in 2018 is to use stock, untouched, inexpensive LS engines, such as 5.3L or 4.8L truck variants.

Those motors tolerate 500-750 horsepower and cost $500 each.

Just need a turbocharger, plumbing is what the $$ goes into.
This way you torch an $500 engine, instead of a $6500 engine each time.
You can go through five engines and still cost less than that one you had built.

 

 

What do you call heads? valve jobs? porting? crankshaft turning? rod bearing clearance measuring? wrist pin lubrication orifice effective diameter? Oil system/pcv modifications? aftermarket pistons? particular cylinder wall finish hone?

There are 999 modifications you need inside an engine which are far more difficult to produce properly than anything you could do outside of an engine.

To put this another way, rebuilt engines typically go 1/8 to 1/30 the mileage of a factory engine because of all the mistakes professional engine builders make, including those passed on by the owner who does not understand for example what a larger than stock bearing clearance entails in a rebuild using standard bearings.

Rebuilding the engine puts you at nearly 1000% more risk of losing expensive parts. And everything is custom. This whole hobby is one big fat custom job. Anyone that comes on a Horsepower-Car oriented forum and claims "I dont want anything custom" then drops $6000 on a fully custom engine that takes 4 months to get back from the machine shop and goes 5,280 miles over the course of 2 years and then fails is pretty damn typical, novice failures, and this is what Novices need to avoid but don't for some reason.

 

1. http://www.yellowbullet.com/forum/sh...50&postcount=1

This thread is an excellent example of what one may face when attempting the rebuild routine.
I suspect the owner has a high amount of experience by the way the post is detailed.
This mistake can happen to those even with high amounts of experience, if only because it is difficult to build an engine properly. He knew better than to attempt it himself so like many had a trusted builder do it.



2. https://www.corvetteforum.com/forums...e-parts-2.html

This thread is a great example because this is what you normally do not get to see. Usually you buy an engine, and run it right away. And then when it fails you can't tell from the exposed/ruined surfaces what caused it. Did the thrust wear come first and THEN this nasty finish? Or the other way around?

Nobody buys an engine and takes it apart right away to inspect all the work done first. But this guy does exactly that to a brand new purchased rebuilt engine from a popular distributor and finds a LOAD of mistakes.

IMO if you want to buy an engine you need to buy two of them identical. Take one apart and if it isn't absolutely perfect in every surface you get more I guess. I mean what else do you want? A factory where the assembly procedure is written down, millions of engines are turned out a year, and computer controlled machines do most of the machine work? The closest thing I can think of to that is the OEM. The expensive forged parts aren't the problem; but they are not really an easy solution either apparently. the lack of attention to detail in every particular surface is critical to performance. And so is cleanliness. Clean and exact is just hard to come by.

 

. Lots of wisdom within this post. Also the reason the big shops are so expensive.

 

If the existing high millage LS is OK, how about a short block rebuild saving money, then dress it out with heads, cam, intake, exhaust. I don't think you HAVE TO buy a new block. You could even take a more phased approach, perhaps starting with a stout shortblock and putting all your other stock stuff on it...few years later exhaust and intake...another few years heads and cam...it would allow you to maintain a budget.

 

I personally wouldn't trade an aluminum LS motor for an iron block unless you are going big boost FI, and mainly drag racing.

I do agree that there are ways of building cheap hp. Find an iron block take-out motor that's in good shape, throw a turbo on it, and run it until it blows up, and then repeat. However, I personally just don't have the time to keep pulling the driveline out of a C5 in my garage. I also like road course racing more than drag racing, so my engine goals are different.

I personally found it cheaper to reuse my existing block and crankshaft vs buying a short block. plus I got to pick what parts I wanted to use. but it would have been faster to just have a new short block show up, vs waiting on a machine shop. There's no such thing as a fast machine shop. They work on their own time, and you'll get your engine back on their time schedule. And a good machine shop will have all the work they can handle. you're just happy to get on their list.

when picking a machine shop, definitely check around. I learned a tough lesson the first time I had the engine in my 4.6L mustang built. I used a top notch shop that has been in the business of building race engines for the last 40 years. However, I later realize that my modular 4.6L motor was not their specialty, in fact it might have been one of the first they did. that motor lost oil pressure at 1500 miles because the bearing clearances weren't right. If I had a SBC motor, they were the best shop around... but not for a modular ford.

So the first question I asked my engine builder for the C5 was how many LS motors have you built. Turns out he did almost exclusively LS motors and has 5-10 builds going at any given time. Most of the speed shops in the area use him, and often drop off multiple engines at a time. You really want someone who builds your type of engine on a regular basis, and really knows the engine well.



Attached is a rough list of the parts that went into my build. You can see how quickly it adds up. And I really searched the internet to find the best price on things, find any holiday sales, plus I work for an auto parts retailer, so a lot of a basic gaskets/sensors/etc I could buy with an employee discount.

If you don't do track events you wouldn't need the oil pan baffles, and instead of the ATI balancer you could save a few bucks with a powerbond. But those are minor savings in the grand scheme of things. And not listed is a new water pump because I was able to reuse mine. And the list doesn't include an upgraded intake manifold.

I also decided this was the right time to install an upgraded DeWitts radiator. I also did new tires/wheels/tpms sensors. I also did Z06 springs and DRM Bilstein shocks. basically this one crack-addict saying to a future crack-addict... Be careful what you start! It's a slippery slope, haha.