BoosterClub

I've always loved corvettes but just could never buy one because of the old midlife crisis guy stigma, and because the interiors kinda crappy. I'm really starting to entertain the idea of buying one to turbo now though.

I see obviously the APS kit, which looks like a pretty good value from the FI world I come from. 625whp ish isn't going to be enough for me for long so I'm wondering if many people have taken their LS3s to 800-1000whp and what kit if any they used and approximate costs. How much does it cost to send an ls3 to a reputable machine shop for building?


I'm no stranger to FI, but I know nothing about american cars.

m R g S r

someone just posted a dyno of a bolt on SC kit onto their LS7...737whp. not too bad. the LS7 has higher comp. than the LS3, so i say with a tune thats on point and some good gas you can break 800whp on an LS3 no problem. how long it will last depends on driving style maintenance etc etc. but if you have the means to build the right twin turbo setup, go for it! or go big single!

BoosterClub

Don't have the means to fabricate it from scratch unfortunately, just install stuff and make minor modifications if needed for more power. I could build an engine but would want to send it off to a machine shop anyway so at that point it's just easier to have them assemble.

In regards to the compression, the higher compression motor should make more power off the same boost unless it's horribly limited on octane.

Really I'm just wondering of an idea of what it would take to see if I should really start researching. I come from BMWs were 500whp costs you 15k and 700whp is your first born.

Drewstein

You'll have to get the motor built to handle the 800+ but the APS kit will do it.

The LS7 is a terrible choice for high hp FI due to high compression and thin walls. Either way you're building a motor so save some $$ and build the LS3.

600rwhp can be had for around $18k when talking turbo kits. 800+ will cost you closer to $30k or more depending on drive train needs etc.

Turbo kits cost twice as much to buy and install. I would recommend one of the awesome supercharger deals out there which are $6500 installed and tuned. With the right kit, you can just upgrade the headunit when you get that built motor if you don't want to buy everything all at once.

Either way, think about your budget and be prepared to double it.

BoosterClub

Nah no one would touch the car but me mechanically. I know there's some vortech units out there that can make some serious power. Anyone stuck a big blower on a built ls3? I didn't really consider a supercharger as be able to make big power for some reason.

It looks like there's a whole lot of companies out there making stuff for vettes.

m R g S r

i was looking on s2ki the other day and someone posted a vid of a 1300hp S/C'ed Z06. let me find it. looked pretty damn fast.

here:
http://www.youtube.com/watch?v=dI8jK...layer_embedded


and about the compression thing, i was referring to making that power on higher octane pump gas, not strictly race fuel. if you're talking strictly race fuel then yes compression doesn't matter as much.

Drewstein

Well the turbo kit will cost twice as much and takes twice as long to install. Since it's more complicated there's more to go wrong. It took several months to get my car dialed in. Now I can go on cruises, drive anywhere etc but it took some patience.

I had a 800rwhp C5 with a D1 on it. Imagine that with a nicely done F1.

PowerLabs

Turbos are not very common on Corvettes because they cost double what a good supercharger kit costs and are double the amount of work to get right. They always seem to have some quirk with heat, oil consumption, etc... You will find that most cars here run superchargers, and most of those are centrifugals. It is cheap, simple, and (by virtue of its simplicity) pretty reliable.
The stock LS3 is good for close to 700WHP before it becomes unreliable. Forged internals will cost you abour $4K, and a supercharger kit capable of your 800-1000WHP goal will need to include a fuel system, 8 rib drive, headers, blower cam, valvetrain, etc... 800WHP can probably be had for about $15. I won't comment on 1000WHP because a LOT can go wrong there; you'd have to spend money on a billet block, driveline, etc... Its beyond what I've bothered to research.

SBCGENII

In order for any ls engine to last at 700hp it would have to be tuned by somebody that was actually good at it even then other factors would come into play. I am sure there are some people on the forum that do this on the side or for themselves that can tune better than some of the sponsor's on here, so be careful. The supercharger kits ecs/AandA/HPE that are out right now are fantastic, They are cheaper than a Procharger kit but come with better parts, make more power and are cheaper. Here are some tt kits though, TTIX, HP, Hinson makes a single front and rear mount kit, PTK, sts, and there are a few shops around that do awsome work. And you definitely dont need a billet block for 1000rwhp .

BoosterClub

^%&$ I was about to say if I really need a billet block for 1Kwhp then I wouldn;t even bother, If we can get 1k out of a little 3.2 liter you guys better be able to get 1k out of a 6.2.

So I think what makes more sense, now that I've looked around some more, would be a YSI + a built block. I like the A&A bracket and intercooler out of the ones I've seen.

I'm trying to figure out exactly what would need to be done for the build, obviously forged rods and pistons, what about the valves and heads? New exhaust valves probably? Ported heads? different heads all together? Just trying to get ideas on cost.

Fuel system is obvious and I would just upgrade driveline parts as the break.

j4three

You shouldn't give up on the turbos just yet. The APS Z06 system comes with a fuel system and will support over 1000+ rwhp on a built motor. There are plenty of examples on this forum. The 625 rwhp you referenced was only 6 psi of boost on a stock LS7 motor.

Put forged pistons in your LS3 and turn the boost up ... you'll get to 800 rwhp and have plenty left if you want to build the motor later. That will cost you $15-20k depending on where you purchase the APS kit.

Yes, turbos will take more time to install but once completed, they are virtually trouble free. That is well worth the extra couple of days it takes for the install IMHO.

Streetfast

Mine turned out alright on a built LS3, I'm not sure if this is considered big power that your looking for. ECS kit and install and tune.


http://www.youtube.com/watch?v=EUeTlBF62Cw

PowerLabs

That is the quintessential ricer argument, right up there with the "HP/L" claims and how that somehow is supposed to mean something (sorry, 200/300/400HP is still only 2/3/400HP and it is not any more impressive if it is coming from a 2L)... I know it by heard because I've used it before back when I was driving turbo Subarus and thought they were the greatest thing in the world .
It is not a good argument though. First of all 1000HP from a small engine comes with a TON of caveats. Primarily:
-Race fuel
-Very poor off boost performance (low compression is mandatory)
-Massive turbo lag (big turbo + small engine + low compression)
-Poor reliability. More power from a smaller engine = more cylinder pressure. More cylinder pressure = more load on the connecting rods, bearings, rings, etc.
barely m
Also, and most importantly, the LS series engines were never designed or intended to see boost. They do fine with some boost, but they won't take NEARLY as much boost as an engine that was designed, developed tested and intented to see boost continuously, under warranty. You'll never get an LS3 to live at the same boost levels you can get a 2JZ / 4G63/ EJ257 / insert random turbo engine here. That is a simple fact of life. Of course, one of those 2 - 3L engines at 20PSI is still barely making what a heads/cam LS3 makes on pump, but stilll... Want a massive boost LS engine? Get one that was meant to see boost. The LS9 will do 1000+ WHP all day long, as will a C5R block, as will any LSX block with the right internals. You can make over 800WHP on a forged internals stock engine but it will get iffy much past that. Its been done, but as one of the forum tuners put it before: There is a big difference between what "can work" and what is reliable. If you want a 1000HP car, be prepared to pay a lot for it. You can pay a lot now, or you can pay a lot over the next several months as things take turns breaking between your engine and driveline. Been there, done that, don't recommend it

Depends entirely on how much power you want. The LS3 heads are quite good; a solid build would be forged internals (rods and pistons), bearings, ARP head studs, re-using your heads with a blower cam, dual valve springs, retainers, LS7 lifters, pushrods. Figure circa 6 grand for that, plus R&R. That's basically what I have with an LS2 . It would be good for about 800WHP. Past that you'd probably want to get a forged crankshaft, at which point you could stroke it to 418WHP and make power a little more easily (more displacement = more airflow at lower boost numbers = lower average cylinder pressure = less chance of anything breaking). Porting the heads would be beneficial then also, since they will start to become a restriction at those high power numbers. On the LS3 you can just port the exhaust, inexpensively ($600 - $1000), and make good gains. The next limitation then would be the studs stretching/head warping and coolant getting pushed on boost... You can mod the block for 6 bolts per cylinder while it is getting built, and run aftermarket heads with 6 bolt mains, but you're still on a factory cast liner, so it would be iffy... Sleeving the block is the safest way to hitting 1000HP, but at that point you can just about afford a billet block, and that, in my opinion, is a better way of doing it instead of carving out the factory block to be something it is not... BUT, both options work, both are tried and proven, and the success of what YOU go with will ultimately depend on who builds it and who tunes it.
Just my 2 cents worth though; the BEST advice anyone can give you when it comes to these high power / big budget builds is to find the best shop in your area, talk to them, and agree on what you want, and how it is to be accomplished.
My other 2 cents worth is to think about what you want all this HP for, and, if you've never experienced it, try to get a ride or drive a car with a lot of power... A lot of people get enamored by the idea of, say, having a 1000HP street car, but then find out that, in the real world, it is a huge PITA requiring constant maintenance and not really being that fast unless you are willing to run full on race compound tires and baby the throttle untill you are going over 100 miles an hour to get traction. Again, to offer some of my personal perspective; the jump from 600RWHP to 700RWHP for me came with a forged engine and methanol injection: I have to keep worrying about the methanol tank being full and keep having to find methanol and refill it, which is a PITA on long drives. I run full on R-Compound tires and can light them up at freeway speeds. Most of the time the car is not appreciably faster before about 70MPH despite the extra 100RWHP since it is traction limited to that point. The R-comps are expensive, have to be special ordered, last 7500 miles, have little grip when cold, and are BEYOND dangerous in the rain after they get down to their wear bars. I love having 700RWHP and I could even, at times, use more (BIG catch here; this is ONLY true on warm days, when the tires are warm, the road is dry and clean, and I have the space to really hammer on it and get the car going feloniously fast) since I love the high speed stuff (190+ MPH runs), but how many people here do that? For your average owner all the extra power means is less traction, more tire bills and that pesky meth kit issue... There is an ideal power number for everyone, and more is not always better... Even for me, and I absolutely LOVE horsepower and speed, for more than half of the year it is either too cold or too wet for me to do anything with this power other than just light the tires up and put the car sideways. Even on the drag strip it is hard to hook up; my Nittos spin 1st and 2nd and net 60' times in the 1.9 - 2.1 second range.

Driveline parts are worth MUCH more money before they are sitting on the ground in pieces, and be aware that if you break an output shaft inside your differential ($235 part, plus an expensive install), or a transmission imput shaft (not sure what that costs), you stand a good chance of splitting the entire transmission / differential apart, and that will cost you over $7500... Something to think about. If you have a manual car the tranny will have to come out for the clutch anyway, you should at least do the diff at that point.

BoosterClub

Holy crap, you completely missed the point and didn't at the same time. I was not starting a retarded ricer argument about how its better to make more power from a smaller engine. I was simply saying that a 6.2 liter v8 block should easily be able to take 1khp, citing my 3.2 liter because as a generalized statements it takes a lot less displacement and cylinders to make 1khp usually. Unless the block is a poor design I would have expected to handle it easily.

Also, the engine I'm talking about has great off boost performance and fully spools by 4k on pump gas.

I don't need to experience it, I already have a brutally fast car, it's at the peak of it's performance though with not much more headroom, and it can't fit that big of tires. Which is why I want to move to a vette, SHOULD have way more headroom and can fit quite large tires, and yes I run dedicated Rcomps on the street and intend to on the vette as well. With 355 slicks you should have traction well below 100mph. and I know what you mean about rain, but why would you drive a high HP car in the rain to begin with.

I also run methanol and have to fill my tank, I don;t find it to be a big deal, tire costs are not either, I live in florida so I don't worry about the cold, I am not an "average" owner who see the expense and lack of low speed traction as an issue. I find 800whp boring now.

Also, work is free for me, I do it myself and have the spare time that it doesn't bother me plus I enjoy it. I'm actually really excited to work on an american engine since it's so much different then the OHC engines I normally work on.




Back to talking about building stuff though.


Youre stating a lot of stuff needing to be replaced, beyond the obvious and what I would expect. I would expect the block to be able to handle 1000hp, I expect to have to build the bottom end, have to port the heads or different castings and get new valves and springs. Obviously expected studs, but you're saying a lot of other stuff that I wouldn't have expected like the heads warping. You're also talking about "carving something out to be something it isn't but there is nothing you can just buy besides a Veyron that is designed to make 1khp off the shelf, this is what we do, start with a good base and modify it to make it better. To me it doesn't make sense to pay 3x as much for an ls9 and then go and replace all the parts you just paid triple for. or at the very least spend the same amount and have a WAY stronger set of materials.

You said the ls9 can handle 1khp all day, but it's my understanding that they definitely have the same casting and possibly very similar finished blocks if not identical. Also the GS ls3 blocks have the ls9s forged cranks in them as well.

I did see the lsx block, and it's something I would definitely consider, for a little extra why not get something bulletproof, I'll take cast iron over aluminum any day.

Vert_Fan

I'm really interested in where this build is going........I'm tuned in for sure !!!


My 0.02

......an engine is not an engine........an early 90s 5.0 block from Ford could not structurally make 1/2 that of a 3.0 Toyota 2JZ.......please come here to use your past experiences from other platforms as a guideline but the engineering (geometry and materials) are completely different.

You have LS3 heads, ask LG what they think of "duty cycles" on those castings.

I think the general greater point missed in almost ALL FI threads is the duty cycles of a build...........just about everything can make XXXX Hp, good luck on some of those builds however.

Ask the big builders who flogs/races their cars the hardest and they'll tell you what survived the massive selection of factory/aftermarket parts, and if you are truly honest with yourself you'll get what you want/need.........all these "what do I need" builds are honestly that simple.

BoosterClub

Really wish I could change the title of the thread now.


Oh I know there's differences between blocks and generalizations are not very appropriate, but at the same time can be somewhat accurate so long as both are done with modern technology and with performance in mind, which I would hope the ls3 is.

The ls3 head castings are poor? Is there a history of them failing? Luckily new heads are fairly cheap. And by cheap I mean way cheaper then BMWs which is 4k for a bare bones block and 5k for a new bare head.... you can see now why I am so interested in getting into the vette.

When I really thought about it though, I want to stick with a factory ecu, I have had nightmares with standalones and semi standalone units. And to do a turbo right you really can't use a factory ecu. Turbos are nice on smaller engines because you get great torque, but you guys get huge torque to begin with.

PowerLabs

And that is exactly what I said. After a certain point, a stock LS3 block is not necessarily the best base to begin with. Also, I imagine you probably have some appreciation for the fact that there is an ENORMOUS difference between a dyno hero that can put down that 1000HP number on the dyno once or twice (Supras are great at that ), and something that really makes 1000HP for a while and doesn't blow up. How do you plan to "use" 1000HP? Are you going to be fighting for traction on the street and doing a burnout at 100 miles an hour? The engine will not really be delivering 1000HP then and you'll be able to do it indefinitely on a street car. Will you take it to the drag strip? That'll be harder, but you will still only make 1000HP for about 8 seconds. Are you going to race it in the mile? That'll be pretty tough. You can probably get a stock engine block with forged internals to make 1000HP a couple of times. You'd be insane to expect that to last a long time. Somewhere in between those two extremes is every response you will find on this forum, which is why I said you should talk to a builder about what exactly you want the car for... That makes all the difference in the world.

The crank on the LS9 block is not the same as the ZR1, but either way, that is not what you should be concerned with.. The LS9 block has all forged internals. Forged rods, not sintered powder ones, and forged pistons. That is why I said it would do 1000HP all day. You mentioned that nothing aside from a Veyron will make 1000HP under warranty. Yes, that is true. But certain engines are much more suited to make that kind of power than others. A good rule is that boosting an engine that was never meant to see boost will always be less reliable. That is why you can pull the supercharger off a 5.4L Ford GT engine and crank it up with twin turbos to 1000HP on basically stock internals, but the same exercise on a 7L LS7 will leave you a pile of nuts and bolts. That's why the LS9 will handle much more power than an LS3. That's why your Supra engine lives at 20 pounds of boost. Now, the real difference, I mentioned already:

The cylinders on a 2JZ are a part of the casting. On a GM aluminum block, the cylinders are steel sleeves; they are much thinner and made of grey cast iron; not as strong. The LS9 cylinders are supposedly stronger, and the LS9 engine uses thicker head bolts to increase head clamping force, along with a 7 layer head gasket.

Technology has little to do with it... "Design Intent" is more like it: The Prius is a technological marvel but it is still slow as hell. It is all about purpose. The LS3 is a 430HP naturally aspirated motor. It will make about double that when boosted; it was not designed to do that, it is not meant to do that, and it won't do it forever. Push it much further and problems will appear. "Are LS3 head castings poor"? Isn't that a bit like asking if a building design was poor because it collapses when a bomb goes off inside it? The LS3 heads are some of the best heads out there for the money, but they are not intended to clamp down an engine making 1000HP; you will push coolant if you try to do that. You can add provisions to it to clamp the heads down with added studs, but, as I mentioned, a better option is to get an aftermarket head with a thicker deck.

Superchargers can make great torque too. And the factory ECU can handle most setups.

It is a boat anchor up front; 110 additional lbs. It will hurt handling. But it is stronger. I'd personally prefer an aluminum block to retain the handing, light weight and perfect 50/50 weight distribution which are some of the biggest sellings points of the car for me...

BoosterClub

Powerlabs, you are missing the points completely, why I want the kind of power I do is my business, though I already explained it, no need continue trying to talk me out of it, it's futile, trust me. Go after the 2000hp lambos, I think that's more my "holy **** how would you ever need that much HP" point.


Understood, you misunderstood what I meant by poor casting, I'm sure they are wonderful NA, I was simply asking for clarification if people have experienced that they have weaknesses under boost. Possibly a citation of such if possible. I already expected the valves would need changing but you seem to be saying the castings will not hold up and new ones would be necessary.

Great, if the ls3 heads can't handle it that's what I would want to do, and something like this is why I am asking.



I don't think it's insane to expect, the displacement is huge. I don't expect stock internals to handle it, but I was expecting the block to, has anyone even seen a cylinder wall crack or a similar block failure or are you just saying this because it wasnt "built for boost" because plenty of blocks not built for boost can run 1000hp reliably.



As far as pushing using an ls9, just stop, I have no intention of using a stock engine, even if it's an ls9 especially one with such a premium as an ls9. I would much rather build an engine with components that can handle much more, balance it perfectly and so on. Looks like there wouldn't be much left but the block and maybe not even that, which is why I see what you;re saying with the ls9, but I'm very sure you could build a much stronger engine then an ls9 for cheaper from aftermarket parts.



Right on LS engines they can, that's what I said and like. On an s54 though you would make like 350 tq and 550hp with a centri blower, that's why initially I wasn't thinking about one because I have become addicted to the torque of a turbo but when I realized they will still make huge torque on these cars it sounded like an obvious better choice since they are easier to tune, cheaper, simpler, more reliable and can run off factory ECUs easily and reliably.



A concern for sure but I intend to corner balance the car after completion.

PowerLabs

Not sure what point you think I am missing: I didn't say another word about why you wanted the power; I tried to illustrate to you how much harder it is to get that vs 800WHP. Not sure where you are getting that idea from.
BTW lamborghinis are full time all wheel drive; they can harness big power a lot more effectively...

Yes, they fail. If you used the "search" function on this forum instead of arguing that just "because it is a big engine it should work", you'd know that. By your reasoning, the LS7 would be the best engine to boost, right? its the biggest one You want to spend a lot of money, you should do a lot of research... You obviously have some pre-conceptions in your mind; maybe you should be searching for them specifically so you can find out if they are true or not, instead of arguing them... Educate yourself. Otherwise you will find a shop that will build you a "1000HP" stock block LS3 car and won't know any better...
Here's another place worth investigatings:



Dude I'm not "pushing" anything. Look under my name: does it say "vendor"? I'm just another enthusiast with a forged, boosted motor. I've been down this path before, talked to vendors, read books on the subject, gotten burned with parts breaking, etc. You're a guy with a Supra who thinks that just because some shop on Youtube makes 1000HP from a 2JZ, an LS3 block should be able to do that and then some more with minimal work.
Also, you can't even buy an LS9 block from GM. I was using it as an example of an LS engine meant for boost, capable of handling 1000 HP, vs taking an N/A motor and trying to push it to that power level.

Corner balancing does not do anything the effect that much weight up front has on braking, acceleration and handling. What are you going to do; jack the front end up so high that the center of gravity shifts back again? You'll be ramming air under the car at speed if you do that.
You take the weight and deal with it. Its fine on a straight line car; it is still 200 pounds lighter than a Gen IV Supra for example. My point here is that for an extra >2K you can get an RHS race block that will be almost as strong, and keep the factory weight.

BoosterClub

1. I don't have a supra, if you read, I do bmws

2. I know I need to do research WTH do you think I made this thread for, I don't claim to know much of anything about LS engines but if you say something that goes against standard logic I'm not just going to believe you if you don't back it up with something.

3. You are pushing the ls9, read your own posts. Regardless there are tons of none meant for boost blocks that make 1khp reliably, and from less displacement, your generalization that if they aren't made for boost they wont take it is poor.

3. No I don't think the ls7 would be a good block, I know it doesn't have meat around the cylinders, from what I have seen the ls3 does though.

4. I never said minimal work, I expected a full engine build.

5. Corner balancing isn't only achieved by height adjustment. Relocation or ballast are quite effective.

6. if you've been down the path then why not share your actual experience, drop all this other ****, condescending/argumentative tone, judgment. All I am asking about is what is going to be necessary to put the power out, I don't need to hear your opinions on how a 1000hp car is dumb. If you want to help, help me find the examples of ls3 blocks that have failed, recommend some head castings that would hold up and flow well, things like this.

If you don't want to help and just want to bicker then just don't help, I'm tired of bickering with you.