Are we going about it all wrong?

JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
13,716
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Texas!!!
I knew the gen III Chevy small block was capable of producing big power, but I read this article in Hot Rod a couple of days ago and was absolutely amazed. You should read the whole article, but to sum it up, they took what they thought was a 5.3 engine from a wrecking yard, opened up the gap on the top ring, put some upgraded heads, a bigger cam, and some bigger injectors in it. They also bolted on a couple of turbos and put down over 1200 HP on an engine dyno. This was on a completely stock bottom end! I found it very interesting.

http://www.hotrod.com/techarticles/hrdp_1109_stock_gm_ls_engine_big_bang_theory/

I'm not getting rid of my truck anytime soon or anything. I was just really impressed with what they were able to do with the motor. BTW, the motor turned out to be a 4.8 instead of a 5.3 like they thought it was.
 

Burn Down

Hotrodder
Sep 14, 2008
7,092
28
48
Boise Idaho
Im a huge fan of the gen III. Some variation of that engine will go into my 67' Camaro. I have been reading about it for awhile now and it is so impressive.
 

whitetrash21

put on da damn helmet day
Apr 29, 2008
4,929
0
36
Vegas
i read that article... then had to re-read it/ Blew my mind. Stock bottom end and it never gave out.... ran into some tuning issues iirc. Amazing what the lsx series can take as far as abuse.
 

GeneralTJI

Turbo Todd
Jun 1, 2010
1,272
0
36
Colorado
Though I'm sure that smallblock made pretty solid torque with that turbo setup...It's the massive torque of the Diesel that cleans our clocks IMO.... everything from the crank itself to the trans, and the rest of the driveline suffers from such massive torque numbers....yes it helps get our heavy trucks up and moving, and it's essential with towing etc. But it puts a lot of stress on everything...
 

THEREDDEVIL

A Bad seed
Jul 28, 2010
512
0
16
44
Godfrey, il
I keep debating on selling my 3 first gen motors and doing a 5.3 swap with a single gt45. I don't have much room in the little vega engine bay or it would b twins. Unbelievable what some guys r doing with these things. Nitrous, blowers, turbos and huge power! That 1200 hp would b unreal in a 2500lb car.
 

duratothemax

<--- slippery roads
Aug 28, 2006
7,139
10
0
Wyoming
Ive been saying for years...dmax guys need to take off their diesel blinders. Yeah the diesel torque is fun. Anyone who says "oh duramax's are awesome, so easy to get power out of!!!" has never worked on a Gen III/IV V8......

Those engines blow the dmax out of the water as far as hp-to-dollar value, and what you can do with stock parts. Not to mention you can pick up a complete junkyard 4.8/5.3 for the price of two duramax injectors.

Anyone who says "gassers drool and diesels rule!" is just being ignorant, IMO. The cost of breaking parts on a duramax gets kinda old and takes the fun out of it.
 

DuramaxPowered

Pushing my luck....
Jan 27, 2008
791
0
0
41
Monroe, MI
which is exactly why I haven't dropped any coin to start building a DMAX motor..............Seriously considering building a 1500 truck with turbo 4.8/5.3/6.0..
 

'03duramax

I love cheer******s
Sep 16, 2006
190
0
16
WA
When I got into diesels back in '05, I was hooked, and just ignored my Camaro. Now 7yrs later I've sold the 408 and just let the car sit. Sad, I definitely miss the LS cars, but the online community of LS owners is part of what drove me away. Though there are some pretty annoying Dmax sites now too, haha.
 

JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
13,716
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Texas!!!
Though I'm sure that smallblock made pretty solid torque with that turbo setup...It's the massive torque of the Diesel that cleans our clocks IMO.... everything from the crank itself to the trans, and the rest of the driveline suffers from such massive torque numbers....yes it helps get our heavy trucks up and moving, and it's essential with towing etc. But it puts a lot of stress on everything...
I agree. It is one of the things I have been concerned about with my upcoming race van project. I'm afraid to scatter the engine by running too much RPM, but I'm tempted to see just how high you can spin one of these motors totally stock before something comes apart. I'm betting it has valve train problems before a rod comes apart.
 

MarkBroviak

DMax Junkie
Vendor/Sponsor
May 25, 2008
2,134
464
83
Danville Indiana
I agree. It is one of the things I have been concerned about with my upcoming race van project. I'm afraid to scatter the engine by running too much RPM, but I'm tempted to see just how high you can spin one of these motors totally stock before something comes apart. I'm betting it has valve train problems before a rod comes apart.

Cough, 5250rpms is where my hardlimit is set and still going...:spit: I'm with you, I am waiting for a valvetrain failure in mine, not worried about the lowerend failing. Wondering where the valves are going to float...
 

JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
13,716
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Texas!!!
Cough, 5250rpms is where my hardlimit is set and still going...:spit: I'm with you, I am waiting for a valvetrain failure in mine, not worried about the lowerend failing. Wondering where the valves are going to float...
For real? You've ran that much RPM on your LBZ? Do you still have a completely stock valve train?
 

McRat

Diesel Hotrodder
Aug 2, 2006
11,249
26
38
64
Norco CA
www.mcratracing.com
While I love the LSx family of engines (we have 2), it's kind of like apples to oranges. Our Duramaxes are amazing because a HD 4x4 tow truck can be made to haul ass fairly easy, even though they are the size and weight of a barn. And somehow get good mileage in the process.

Things to note:

1200HP on an engine dyno normally translates to 900-1000rwhp.
A 600rwhp diesel in a 7000LB truck will outperform a 600rwhp gas engine in the same truck. Diesels have much flatter HP curves, ie - more average HP.

Race gas is $7.50 gallon and rarer than diesel fuel is.

Minor tuning errors in turbo gas engines are expensive.
 

mckey73

Ethanol suks make whiskey
Feb 14, 2007
34
0
0
And everyone was giving me a hard time about swapping my lb7 for a lq4, sheesh. How many ls2 aftermarket parts are just lying around peoples garages? I can get a whole donor truck for about $400 to $800 less than new injectors - of course that doesn't include the $3k to build a n.a. 6.0 and tune it.
 

Iceman56

New member
Jan 19, 2009
867
0
0
Madison, SD
While I love the LSx family of engines (we have 2), it's kind of like apples to oranges. Our Duramaxes are amazing because a HD 4x4 tow truck can be made to haul ass fairly easy, even though they are the size and weight of a barn. And somehow get good mileage in the process.

Things to note:

1200HP on an engine dyno normally translates to 900-1000rwhp.
A 600rwhp diesel in a 7000LB truck will outperform a 600rwhp gas engine in the same truck. Diesels have much flatter HP curves, ie - more average HP.

Race gas is $7.50 gallon and rarer than diesel fuel is.

Minor tuning errors in turbo gas engines are expensive.


E85 is like a $1.50 though and is at about as many pumps as diesel is around here. E85 blown motors seem to be the new thing on the street and it sounds like there pretty awesome.