Are we going about it all wrong?

02greysixer

Active member
Jun 4, 2011
1,829
7
38
North Central FL
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.

I agree, a 600 horsepower 1/2 ton truck would be fun for sure. But with gas you'd pay for all that power a lot more in the fuel economy than with diesel. Best milage I've ever seen from a 5.3 truck was 17 something. That was hyper mileing on an open flat highway. Truck had free flowing flow masters, a diablo on economy, a cold air intake, and a free flowing MAF. When adding a turbo or supercharger to that youre lucky to even see the same milage as a stock truck. At least with our diesels a 600 hp truck will get better milage than when it was stock. Of course that all goes out the window if something happens with the duramax and it needs to be built. This is speaking stock long block to stock long block.

This is just my opinion and experiences, im sure lots of people will disagree. But one of the main reasons I bought a diesel was to make big power and still see around 20mpg.


Sint frum tha orijinul smert fone
 

blk smoke lb7

<-----Lots of green $
Nov 8, 2010
5,694
0
36
57
belvidere,ill
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...
X2
 

Evan@InglewoodTrans

yerp
Vendor/Sponsor
Aug 5, 2010
3,118
65
48
40
Western MA
I get asked daily why I am putting so much money into a diesel truck to make it fast when I could buy a gasser and make it faster for much cheaper. The answer for me is easy everyone has fast gas cars and trucks and that's not what I want it has nothing to do with thinking it's easier to get power from a diesel motor. Even if the parts are more expensive and it's not practical to have fast 4x4 diesel truck that's what makes it so fun.
 

68skylark455

Larry the "Stroker"
Aug 7, 2008
1,091
0
0
Texas
www.larrysperformancepalace.com
This is why I opted for the LQ9/4l60e in the burban. The tuning may be eaiser then most think since there are alot of people out there doing them. I copied the tune from the truck before I dismantled it. It was done by a company here in Texas with HPtuners but efilive copied it like it was one of theirs even though they are completely different:thumb: I have copied several "stock" programs that come thru the shop. The 6.0 awd escalade huals ass so I got one of them programs too. I have the stock turbo off of blackie and have been "thinking" on how to maybe make it work just to test the theory. Why buy parts when you have them sitting around:woott:
 

DuramaxPowered

Pushing my luck....
Jan 27, 2008
791
0
0
41
Monroe, MI
My thoughts are keep the LMM just the way it sits with stock cp3/injectors/twins, and build a second truck. LMM runs good the way it sits, doesn't need a built motor and can do everything I need. A regular cab shortbed 1500 with a turbo 5.3 would haul ass and be a fun street truck IMO.....
 

GeneralTJI

Turbo Todd
Jun 1, 2010
1,272
0
36
Colorado
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.

Check around again, in my area it has gone way up :( I run my wrx on e... it's downright amazing stuff. EGT's dropped about 200 degrees, so I can run much leaner afr's, more timing (can actually exceed MBT under big boost if your not careful).

It's very forgiving stuff... though it takes some time tweaking your tune to get it to start in cold weather... and economy goes down because you burn approx. 30% more... but well worth it for a performance application!!
 

wrcknkrw

Member
Feb 21, 2008
447
0
16
roy ut
The gas motors can be built considerably cheaper and very fast. I'm putting a 6.0l in my 59 chevy truck. I love my diesel and will not get rid of it because of it being so versatile. It's fast can beat most vehicles on the street get decent mileage and still tow what ever i hook up to it without caring.
 

TrentNell

Finally underway !!!!!
Jul 7, 2008
7,543
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slc tuah
I love something fast diesel or gas makes no difference to me , but as fast gasser just doesn't feel the same to me , I can never get over the "rubber band " felling of the power on these trucks , and seems like the spedo is climbing way faster than RPM once your in the higher gears .



I still think there is nothing else out there that can be built to do so many things well , and be made so fast with almost no loss of function if done the right way , with as far as thew industry has come it is very possible to have a low mid to low 10 sec truck that can still tow , be daily driven , ect . Its the reliability holding us back IMOP .
 

PAT

EASY DAY
Aug 21, 2011
1,100
0
0
your back yard
I love something fast diesel or gas makes no difference to me , but as fast gasser just doesn't feel the same to me , I can never get over the "rubber band " felling of the power on these trucks , and seems like the spedo is climbing way faster than RPM once your in the higher gears .



I still think there is nothing else out there that can be built to do so many things well , and be made so fast with almost no loss of function if done the right way , with as far as thew industry has come it is very possible to have a low mid to low 10 sec truck that can still tow , be daily driven , ect . Its the reliability holding us back IMOP .

Trent... I don't think I've ever disagreed with anything you have said... But honestly I think that it's not durability that is the biggest deal. I think it's the price of duramax performance. $3k for a set of rods is astronomical. Even though I've partaken. But it's almost as if you HAVE to be sponsored or HAVE to have really deep pockets to pass mid 11's.
 

TrentNell

Finally underway !!!!!
Jul 7, 2008
7,543
0
0
44
slc tuah
Trent... I don't think I've ever disagreed with anything you have said... But honestly I think that it's not durability that is the biggest deal. I think it's the price of duramax performance. $3k for a set of rods is astronomical. Even though I've partaken. But it's almost as if you HAVE to be sponsored or HAVE to have really deep pockets to pass mid 11's.

100% true , yes the costs suck and I feel your pain because I have never really had a lot of coin to use on my own truck , its been a struggle from day 1 and that is a lot of the reason I have always tried to keep the stuff I offer on affordable side .

But were reliability comes in is even though its expensive if you only had to do it once every 5 years it would be OK , but to spend the huge amount of coin to build a motor and have a 6 month - 36 month average life ( unless you dont push it hard ) and have to do it again is why I think it is holding us back.
 

turbo_bu

Member
Mar 27, 2007
198
6
18
Central IL
I have to say I miss my 5.3! I love the power of the DMax but I do miss the high rev 5.3.

Here is a guy from the forum I get on, he went 10.5 on a 4.8 front mount. Bad ass!
http://www.performancetrucks.net/forums/drag-racing-139/fooses-rig-2011-best-passes-493124/

performancetrucks and LS1Tech.com ... same basic web sites that are focused on performance LSx engines. On the LS1Tech site, there is a section devoted to nothing but forced induction. That is the "other" forum that I read on an almost daily basis .. the turboforums.com is another very good one to sit and read through. Though you will be there for a LONG time trying to digest is all.

As for stock stuff, there is even going to be a "stock block" shoot out this spring. http://www.stockshortblockshootout.com/

I can only imagine how fast of times these guys are gonna post! There have been lots of cars well into the 9's and even 8 seconds with nothing but a turbo LSx setup.
 

PAT

EASY DAY
Aug 21, 2011
1,100
0
0
your back yard
100% true , yes the costs suck and I feel your pain because I have never really had a lot of coin to use on my own truck , its been a struggle from day 1 and that is a lot of the reason I have always tried to keep the stuff I offer on affordable side .

But were reliability comes in is even though its expensive if you only had to do it once every 5 years it would be OK , but to spend the huge amount of coin to build a motor and have a 6 month - 36 month average life ( unless you dont push it hard ) and have to do it again is why I think it is holding us back.

Agreed. But engine life span for your type of truck is quite a bit different than the majority. If I had to rebuild my motor every 36 months I'd shoot myself. It's just the damn suspension that kills me!!! GRRR
 

PAT

EASY DAY
Aug 21, 2011
1,100
0
0
your back yard
performancetrucks and LS1Tech.com ... same basic web sites that are focused on performance LSx engines. On the LS1Tech site, there is a section devoted to nothing but forced induction. That is the "other" forum that I read on an almost daily basis .. the turboforums.com is another very good one to sit and read through. Though you will be there for a LONG time trying to digest is all.

As for stock stuff, there is even going to be a "stock block" shoot out this spring. http://www.stockshortblockshootout.com/

I can only imagine how fast of times these guys are gonna post! There have been lots of cars well into the 9's and even 8 seconds with nothing but a turbo LSx setup.

That looks like it will be an awesome race to watch! Prob a whole lot of carnage to be seen.

Question though.... Ummmmm... How do they know that you have stock rods and crank? I've seen people have to pull valve covers for some sort of inspection. But how do you check for stock rods?
 

GeneralTJI

Turbo Todd
Jun 1, 2010
1,272
0
36
Colorado
With a fast diesel truck you "get" more... HD truck capable of towing, hauling, 4x4 for weather/off road, better mileage etc. You also pay more for all this :( Fast gas car/truck you don't have the complete package, but you spend less.... somewhat relative I guess?

I love my car!! it's a blast to row through the gears... but there is something about stomping someone in a big heavy diesel truck that keeps us coming back and spending more money I guess :rofl:
 

McRat

Diesel Hotrodder
Aug 2, 2006
11,249
26
38
64
Norco CA
www.mcratracing.com
If you take a stock Dmax, throw a $400 tuner on it, you have about 400rwhp (~530HP at the crank). No other changes necessary.

Where are you going to find a 530HP pickup that will actually tow anything?
 

taylorbok

Member
Jan 31, 2011
113
0
16
If you take a stock Dmax, throw a $400 tuner on it, you have about 400rwhp (~530HP at the crank). No other changes necessary.

Where are you going to find a 530HP pickup that will actually tow anything?

That right there is why the "average" guy loves diesels, he can put his tuner on and still tow his camper, sleds, car hauler every weekend. where to get that extra 150hp out of a gas engine is a few thousand dollars and a full motor build, vs plugging in a tuner and away you go.

Its the guys that are doing full motor builds on there d max that realise a race engine gas truck would be cheaper and faster. but you cant tow with the race truck
 

Kat

Wicked Witch of the West
Aug 2, 2006
17,899
13
38
60
Norco, CA
All I'm going to say is that I was faster in Casper then in the Meanie this day he towed me to the track :eek:

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Iceman56

New member
Jan 19, 2009
867
0
0
Madison, SD
Check around again, in my area it has gone way up :( I run my wrx on e... it's downright amazing stuff. EGT's dropped about 200 degrees, so I can run much leaner afr's, more timing (can actually exceed MBT under big boost if your not careful).

It's very forgiving stuff... though it takes some time tweaking your tune to get it to start in cold weather... and economy goes down because you burn approx. 30% more... but well worth it for a performance application!!

I haven't looked for awhile I just thought that's about what it was, my bad... Yeah I have been doing some research on it, sounds awesome basically like alcohol. I guess you can run a ton of boost and cylinder pressure without DET.

I would love to run it in my turbo snowmobile but the cold start and bad economy wouldn't work the best for sledding