408 vs 388 vs ? For Boost
04-24-2018, 04:32 PM
#1
Teching In
Thread Starter
408 vs 388 vs ? For Boost If this isn't the right place to post this, please move where necessary. I'm usually in the racing section and not much around the tech side so I apologize.
Here soon I am planning on buying a bare block to start an LS build. I come from Coyotes so I am not really keen on LS's when it comes to most things besides the basics. I am going to be doing a long build to swap into a C5z in the future and since I am going to buy my block in the next coming month(s) I am gonna start searching for answers.
First thought I had was to buy a 6.0L block and do a 408ci assembly in it. I was likely gonna do Molnar PWR ADR rods (Molnar is huge in the Mod Motor world and everyone loves them and they are proven to hold a lot of power) and Diamond pistons.
Second thought was the basic 5.3, and do whatever people have been doing CI wise for that block that would work really well with boost.
Third is the obvious 388 setup. What block/internals are most running with that setup? I'm not trying to spend a **** ton on a Dart block or something of that nature. This is why the 6.0/408 has my attention because it's cheap, proven, and will hold whatever I want to throw at it.
Power goals will be anywhere from 800-1200 or so whenever I would feel the need to turn it up and not be a scared ***** with the car.
Setup will be one of the top, unless I find a more efficient route, paired with a good set of heads, Mamo MSD, LS9 gaskets, and I'm still up in the air on a YSi or single turbo, engine bay mount. I had a turbo Coyote and liked it (just seems like it'll be a bit of a bitch to get a large sized turbo to fit in the engine bay) but I really enjoy a nicely setup Centri. However, everyone knows turbos run the world so it's gonna be a good option.
Compression is another thing with LS's. I know Coyote's love 11:1-11.5:1 but LS's are a tad different. Would 10.5:1 be too much with a car running that power levels on pump E85 all the time? 10.5:1 would be the area I want to try to shoot for, but am not above going lower.
I am sure I will think of more questions to ask and I will update this thread when I do, I'm sure most of them will be noob questions too so bare with the Coyote guy here lol.
Here soon I am planning on buying a bare block to start an LS build. I come from Coyotes so I am not really keen on LS's when it comes to most things besides the basics. I am going to be doing a long build to swap into a C5z in the future and since I am going to buy my block in the next coming month(s) I am gonna start searching for answers.
First thought I had was to buy a 6.0L block and do a 408ci assembly in it. I was likely gonna do Molnar PWR ADR rods (Molnar is huge in the Mod Motor world and everyone loves them and they are proven to hold a lot of power) and Diamond pistons.
Second thought was the basic 5.3, and do whatever people have been doing CI wise for that block that would work really well with boost.
Third is the obvious 388 setup. What block/internals are most running with that setup? I'm not trying to spend a **** ton on a Dart block or something of that nature. This is why the 6.0/408 has my attention because it's cheap, proven, and will hold whatever I want to throw at it.
Power goals will be anywhere from 800-1200 or so whenever I would feel the need to turn it up and not be a scared ***** with the car.
Setup will be one of the top, unless I find a more efficient route, paired with a good set of heads, Mamo MSD, LS9 gaskets, and I'm still up in the air on a YSi or single turbo, engine bay mount. I had a turbo Coyote and liked it (just seems like it'll be a bit of a bitch to get a large sized turbo to fit in the engine bay) but I really enjoy a nicely setup Centri. However, everyone knows turbos run the world so it's gonna be a good option.
Compression is another thing with LS's. I know Coyote's love 11:1-11.5:1 but LS's are a tad different. Would 10.5:1 be too much with a car running that power levels on pump E85 all the time? 10.5:1 would be the area I want to try to shoot for, but am not above going lower.
I am sure I will think of more questions to ask and I will update this thread when I do, I'm sure most of them will be noob questions too so bare with the Coyote guy here lol.
04-28-2018, 12:48 AM
#3
I have run a turbo LS9 setup for a few years and never changed a head gasket...... ran easily 50+ 1/2 mile passes/freeway passes over 200mph in 5th gear on cheap $2/gal e85 and 100+ 1/4 mile long pulls. If you want reliability.... start with the best OEM stuff out there.... 
I can't even use the power this thing makes on a 275/50/15 M/T ET Street DR and 3.31 gears (T56 Magnum). Conservative timing ramping in boost by gear/time. Stock LS3 intake/90mm TB, Precision 88mm T4 turbo (1450-1500hp rating). It pulls like a mad man in 4th and 5th gear when I can finally pour in some power.
Fresh LS9 longblock for sale ready to go!
https://ls1tech.com/forums/parts-cla...hoice-cam.html
I assume you are aware that your stock transaxle/diff is nowhere up to the task of handling 800rwhp!?!?! Start shopping for an '08+ Z06 TR6060/diff setup.
I can't even use the power this thing makes on a 275/50/15 M/T ET Street DR and 3.31 gears (T56 Magnum). Conservative timing ramping in boost by gear/time. Stock LS3 intake/90mm TB, Precision 88mm T4 turbo (1450-1500hp rating). It pulls like a mad man in 4th and 5th gear when I can finally pour in some power.
Fresh LS9 longblock for sale ready to go!
https://ls1tech.com/forums/parts-cla...hoice-cam.html
I assume you are aware that your stock transaxle/diff is nowhere up to the task of handling 800rwhp!?!?! Start shopping for an '08+ Z06 TR6060/diff setup.
Last edited by gnx7; 04-28-2018 at 12:59 AM.