Buzzboy317

I am rebuilding my LS6 and am looking for input on the two options I am currently considering.

Option 1 - Rebuild as LS6 with added Edlebrock E-Force supercharger, CNC ported 243's and performance cam. Plan to do this in two stages because of budget. Build the motor first and add the supercharger later. Tuning issues??

Option 2 - rebuild as a EFI 383 Stroker

This will be in my 2005 CTS-V used for street and track days.

Advice? Suggestions?

Thanks

mchicia1

iTrader: (5)

Track days as in road racing or drag racing? If it's drag racing, go with option 1. If not, go 2.

1nasty86

iTrader: (63)

I love n/a simplicity..... but that's just me

JakeFusion

iTrader: (7)

For road racing, I'd stay away from a roots type blower. I'd do turbo or NA.

The cost of the 383 stroker is almost the same as like an LS3 based 416. You're within about $1000 either way. I'd do the 416. More torque and power to help move the CTS-V.

Detoxx03

iTrader: (14)

If the eforce is your only supercharger option i'd stay n/a.

badazz81z28

iTrader: (6)

Apples and Oranges comparison here. The Supercharger alone will cost more than the 383 build with 243s. I would build a 383 and invest in some really good heads like AFR. You could easily make 500 horsepower to the tires, drive it everyday and not have to worry about heat soak. Superchargers like the E-force are meant for stock motors where it's easier to slap it on. Since you are pulling the engine anyways, I wouldn't go Force induction.

badazz81z28

iTrader: (6)

Jake, are you referring to buying the short block ready to go? I know you can get a 383 rotating assembly for close to $1500. All that would be left is machine work (same for both builds). Going out and buying an LS3 is money.

I would not go Turbo if the intent is road course or auto cross. You want NA or a blower for that. Turbos work well on the strip and the street for manners and gas mileage.

JakeFusion

iTrader: (7)

A 383 rotating assembly is more like $2500 from what I've seen. That's with a K1 crank (800), Compstar Rods (550), and Wiseco Pistons + Rings (750) + Bearings ($200) and balancing ($200). You can go a little cheaper on the rods. But it doesn't save a whole heck of a lot. Plus the machine work and labor is going to be at least $1k. So you're at 3500 with your block. A 416 can be had from Thompson for 4600. And it includes pretty similar components. Thus, if you're spending that sort of money, might as well get the bigger bore and better block.

I wouldn't do Supercharger on a road course. That's a lot of stress on the crank snout with varying RPM. A turbo allows you to bring boost up and down with the wastegate/blowoff valve without much issue and introduces no stress or harmonics to the varying load and RPM of the crank. A lot of really good road race cars are in fact turbo (Evo, 911, GTR). Yeah, I know the ZR1 has a roots type supercharger, but I'd rather have a Z06 with the Z07 package vs a ZR1 if I were road racing.

Buzzboy317

Thanks. That is all great info. I'm kinda attached to the original LS6 block and 243 heads because it's a somewhat unique setup.

Lot's of negatives on the E-force...I'm surprised but that is why I'm asking.

The machine shop I'm talking to wants to use a 3.75" stroke with 0.020" over instead of the typical 4.00" stroke I see most often. Guessing this is for quicker revs.

He is asking $8,200 for the complete 383 build and is giving me a 3yr/36K warranty. The rotating assembly alone is $2600 but this guy is supposed to be really good. I'm sort of tempted to build it myself but the machining and building the heads seams like most of the labor. I'd just be assembling the lower end and bolting the heads on...right?

Should I go to the 85mm or 90mm throttle body and maybe a custom flow body?

JakeFusion

iTrader: (7)

.020" is a long shot in an LS6 block. Typically they can be honed .008" and that's about it.

If you want to keep your block, send it to ERL and have new sleeves put in and run a 454.

badazz81z28

iTrader: (6)

Texas Speed seems to have a good price on a 383 rotating assembly.

http://www.texas-speed.com/p-787-tsp...-assembly.aspx

JakeFusion

iTrader: (7)

Yes. That $2500 comes from them, since that's the cheapest you'll find.

If you notice, I added the $440 for bearings (and I'd go Clevite) and balancing that the $1610 price does not include but are required. I also opted for better pistons than the Mahle. $50 there. I have no idea what the TSP Crank and Rods are or who makes them. K1 is a $200 upgrade and Compstar is a $160 upgrade.

Point is, you can try to save a few hundred here or there, but you're still up over $3k for a 383.

DMM

If you're planning a 383, I would go through Thompson or Texas Speed. What they offer have been proven time and time again.

If you intend to do the E-Force, there are a few things you need to do differently. First, the 243's are not a good idea. You'd be much better off going with heads that have around a 70cc chamber (I used stage III 317's). I would honestly go with a forged 6.0 and use the LSA/LS3/L92 heads rather than go with the cathedral heads as it will be much easier all things told.

The E-Force route is the much more expensive of the two, although the four or five of us that have them are running around 550-600 whp (only one of which is forged) with very conservative setup's. Tuning wise, the '04-'05's are better off with a 2 BAR OS (like I have) while the '06-'07's can use the OE blended MAF tune with the LS3/7 MAF. I have not had any issue's tuning mine at all, drivability and performance are phenomenal. If you'd like to get some real world feedback on the E-Force, PM me.

badazz81z28

iTrader: (6)

Both builds would require new pistons, rings, bearings and a balance so I didn't factor that in. Side by side build, the rotating assembly alone is the variable that separates the two builds. The supercharger alone is still a lot more $$

JakeFusion

iTrader: (7)

Machine shop labor is very high. The machining and assembly is going to be $1000+ from all the machine shops I've talked to...

maxpower_454

iTrader: (7)

I have a couple excellent machine shops in my area and they built a couple engines for me in the past. Prices below:
$150 assembly
$150 bore
$200 balance
$75 hot tank

badazz81z28

iTrader: (6)

Am I missing something here? The way I understand the scenario...he is "rebuilding" either option. So the machine work, the assembly, the balance etc...etc.. is a factor for both builds so NOT a factor to consider in comparison.

If we wants to go 383 stroker he is looking at $1600 over just rebuilding the LS6.

The option of rebuilding the LS6 (-$1600) and adding a SC (+$5000) = $3400

The option of building a 383 (+1600) and not adding a SC (-$5000)= -$3400 (Saving)

The 383 is the cheaper option.

frogpoopisgood

iTrader: (1)

Honestly if money is not an issue I would probably do a turbo setup using the ls1 truck manifolds, run stock bottom also... You'd make 600 easy.

*Edit:
You can get a really nice complete setup for under 4k.