Stock bottom end fun - Competition Diesel.Com

Austins_lb7 · 03-01-2019, 01:13 AM

Hey guys, so I've hit the 600hp mark on the stock bottom end of my lb7. My truck runs really clean on the bigger tunes which I dont mind but I feel it's too lean (absolutely no smoke when mashing on it). 4th tune I was losing rail when I first raced it and had the tunes edited afterwards.Tunes are by Idaho rob. I sled pulled this last season and saw 2000 egts on my cts2 monitor which is cooking pretty good. Do you think a dual fueler would help with egts? I'm not really into water meth so I'm hoping more fuel will help lol I'm also thinking if I add more fuel I can run the truck in a lower tune and still have 600hp? Any input would be great! Ps I have a spare lbz block sitting on the shelf just incase she decides to party without my permission.

JWhite · 03-01-2019, 01:37 AM

More fuel won't cool it down unless you start drowning it with fuel, then bye bye bottom end. Want it cooler, you need more turbo

Austins_lb7 · 03-01-2019, 02:01 AM

Quote:

Originally Posted by JWhite

More fuel won't cool it down unless you start drowning it with fuel, then bye bye bottom end. Want it cooler, you need more turbo

You think the 69sxe is too small? I only hit 24lbs of boost in my big tune and the turbo is rated for 45lbs. I might be purchasing a 472sxe from a friend in a few weeks just for ****s and giggles. I figure if I drown it with fuel and run it in a lower tune it wont scatter. 5th tune is 600hp currently.

wwentzler · 03-01-2019, 08:04 AM

Quote:

Originally Posted by Austins_lb7

You think the 69sxe is too small? I only hit 24lbs of boost in my big tune and the turbo is rated for 45lbs. I might be purchasing a 472sxe from a friend in a few weeks just for ****s and giggles. I figure if I drown it with fuel and run it in a lower tune it wont scatter. 5th tune is 600hp currently.

You have a bad boost or drive leak. There is no reason to drown with fuel at that level.

JWhite · 03-01-2019, 08:11 AM

Quote:

Originally Posted by Austins_lb7

You think the 69sxe is too small? I only hit 24lbs of boost in my big tune and the turbo is rated for 45lbs. I might be purchasing a 472sxe from a friend in a few weeks just for ****s and giggles. I figure if I drown it with fuel and run it in a lower tune it wont scatter. 5th tune is 600hp currently.

Like the other guy said, you probably have a boost leak, or you're not reading boost with the right equipment. Over fueling a diesel to cool down EGTs will black out a 4 lane highway, you're thinking about this backwards

Austins_lb7 · 03-01-2019, 09:33 AM

Quote:

Originally Posted by JWhite

Like the other guy said, you probably have a boost leak, or you're not reading boost with the right equipment. Over fueling a diesel to cool down EGTs will black out a 4 lane highway, you're thinking about this backwards

I'm using a extension pack on the cts2 and the 0-100psi sensor is located right in the middle of the y-bridge(that's where hsp tapped it) do you think that's in the wrong location? The regular boost guage from the monitor does read boost differently (around double at some points) but it can only read so far due to being an lb7. I believe that map sensor the monitor is reading off of is farther up on the y bridge tubing.

JWhite · 03-01-2019, 11:15 AM

Get a mechanical gauge on it to check. There's no reason to have more than a couple psi difference between two locations. Is the sensor from edge? I haven't heard great things about them

*IdahoRob* · 03-01-2019, 11:25 AM

I recommend getting some real gauges. I don't believe what your boost or egt reading are telling you. Give that edge to a buddy with a stock truck.

Your truck is not too lean, i promise. Clean running 600hp is a great set-up.

MAXX IT OUT · 03-01-2019, 01:36 PM

Granted I have a custom .83 housing on mine, but I see 45-50 PSI of boost on mine threw a 100psi sensor on my Edge. As said above, check for a exhaust leak or boost leak, you should have no problem breaking 600Hp with the above set up.

Austins_lb7 · 03-01-2019, 03:06 PM

Quote:

Originally Posted by JWhite

Get a mechanical gauge on it to check. There's no reason to have more than a couple psi difference between two locations. Is the sensor from edge? I haven't heard great things about them

I'll try and get a mechanical gauge on it and see what's up. I figured since the sensor up top is in a 3inch tube it sees better pressure than than being in the middle of where the air separates into the heads but I could be wrong.The sensor is from edge. Maybe my y bridge gaskets failed as well, I have a stock pile at work and I'll swap them out just for safe keeping.

Austins_lb7 · 03-01-2019, 03:09 PM

Quote:

Originally Posted by MAXX IT OUT

Granted I have a custom .83 housing on mine, but I see 45-50 PSI of boost on mine threw a 100psi sensor on my Edge. As said above, check for a exhaust leak or boost leak, you should have no problem breaking 600Hp with the above set up.

Where is your sensor located? I have a .91 ar housing, it should be relatively close to what you're seeing.

Austins_lb7 · 03-01-2019, 03:23 PM

Quote:

Originally Posted by IdahoRob

I recommend getting some real gauges. I don't believe what your boost or egt reading are telling you. Give that edge to a buddy with a stock truck.

Your truck is not too lean, i promise. Clean running 600hp is a great set-up.

The tunes are great and the truck runs really well, my egts never get close to 2k when I'm driving. Do you think the tunes are setup to limit me to 600? If so it would make more sense. I dont want to go over 600 but id like to know if theres more in the truck than what its putting down.

JWhite · 03-01-2019, 03:34 PM

Not sure what your 42% pump is, but I imagine it's a modded stock stroke setup. The most you'll see on those is around 600-625. You could give it more fuel and possibly pick up a few hp, but it would be on the ragged edge of losing rail pressure. I would put money on Rob set you up right

MAXX IT OUT · 03-01-2019, 04:13 PM

Quote:

Originally Posted by Austins_lb7

Where is your sensor located? I have a .91 ar housing, it should be relatively close to what you're seeing.

Mine is in the Y bridge.

Austins_lb7 · 03-01-2019, 07:41 PM

Quote:

Originally Posted by JWhite

Not sure what your 42% pump is, but I imagine it's a modded stock stroke setup. The most you'll see on those is around 600-625. You could give it more fuel and possibly pick up a few hp, but it would be on the ragged edge of losing rail pressure. I would put money on Rob set you up right

The pump is a industrial 42%over stock pump. Thats kinda why I want a dual fueler and dial it way back so that valley pump isnt working so hard in that final tune.

TheBac · 03-01-2019, 08:02 PM

Takes me back 10 years. Gotta love a crazy bastard trying to push 600+ thru an LB7.

JWhite · 03-01-2019, 09:12 PM

Quote:

Originally Posted by Austins_lb7

The pump is a industrial 42%over stock pump. Thats kinda why I want a dual fueler and dial it way back so that valley pump isnt working so hard in that final tune.

Yes the valley pump won't work as hard, but I'm not sure where you're getting that you'll be able to dial it back and make the same power?

Austins_lb7 · 03-01-2019, 09:58 PM

Quote:

Originally Posted by JWhite

Yes the valley pump won't work as hard, but I'm not sure where you're getting that you'll be able to dial it back and make the same power?

Is there no way to adjust my pulse widths after installing dual fuelers? I dont specifically know how tuning works in that area.

Austins_lb7 · 03-01-2019, 11:20 PM

Quote:

Originally Posted by TheBac

Takes me back 10 years. Gotta love a crazy bastard trying to push 600+ thru an LB7.

I blame it on my boss, he sold me the truck 5 years ago and I've had the itch ever since.

TheBac · 03-02-2019, 05:21 AM

Jwhite, I think he may be confusing running dual cp3s with running larger injectors, so he can turn down pulse and timing.

Austin, LB7s like rail kept above 21000 at a minimum to keep from losing power. The higher the pressure you're able to maintain, the better. Otherwise turn timing and/or pulse down until you see you can maintain pressures.
Larger injectors will help you keep timing and pulse reasonable, which helps immensely with keeping the spray pattern in the piston bowl, but they don't help with keeping rail pressure up at the same power level.
If you go bigger injectors, I'd also do at minimum a 10mm cp3 or dual setup. Stock cp3 alone won't be able to keep up, and you'll simply lose power.
Boy, those LB7 rods are going to hate you, if they aren't bent already. Have you done a compression test yet to check?

03-01-2019, 01:13 AM	#1
Austins_lb7 Name: Austins_lb7 Title: Rookie Status: Not Here Join Date: Dec 2018 Member`s Gallery Posts: 16	Stock bottom end fun Hey guys, so I've hit the 600hp mark on the stock bottom end of my lb7. My truck runs really clean on the bigger tunes which I dont mind but I feel it's too lean (absolutely no smoke when mashing on it). 4th tune I was losing rail when I first raced it and had the tunes edited afterwards.Tunes are by Idaho rob. I sled pulled this last season and saw 2000 egts on my cts2 monitor which is cooking pretty good. Do you think a dual fueler would help with egts? I'm not really into water meth so I'm hoping more fuel will help lol I'm also thinking if I add more fuel I can run the truck in a lower tune and still have 600hp? Any input would be great! Ps I have a spare lbz block sitting on the shelf just incase she decides to party without my permission. __________________ 02 cclb, 42% pump, s369sxe, 45% s&s injectors, 625 studs, stage 5 ppe trans, socal beehive springs, Carrillo pushrods, ppe uppipes and manifolds, hsp piping kit. 1/4 13.3 dyno 596hp

03-01-2019, 01:37 AM	#2
JWhite Name: JWhite Title: Trained monkey Status: Not Here Join Date: Aug 2009 Location: F Burg Ohio Member`s Gallery Posts: 1,817	More fuel won't cool it down unless you start drowning it with fuel, then bye bye bottom end. Want it cooler, you need more turbo __________________ GMC with a LiLLY

03-01-2019, 11:15 AM	#7
JWhite Name: JWhite Title: Trained monkey Status: Not Here Join Date: Aug 2009 Location: F Burg Ohio Member`s Gallery Posts: 1,817	Get a mechanical gauge on it to check. There's no reason to have more than a couple psi difference between two locations. Is the sensor from edge? I haven't heard great things about them __________________ GMC with a LiLLY

03-01-2019, 11:25 AM	#8
IdahoRob Name: IdahoRob Title: Comp Diesel Sponsor Status: Not Here Join Date: Apr 2006 Member`s Gallery Posts: 2,337	I recommend getting some real gauges. I don't believe what your boost or egt reading are telling you. Give that edge to a buddy with a stock truck. Your truck is not too lean, i promise. Clean running 600hp is a great set-up. __________________ Adrenaline Truck Performance "Max'd Out" SoCal Engine, Randy's Trans, DDP 9.36@154 MPH SS legal trim. Last edited by IdahoRob; 03-01-2019 at 11:26 AM.

03-01-2019, 01:36 PM	#9
MAXX IT OUT Name: MAXX IT OUT Title: RUNS AGAIN Status: Not Here Join Date: Aug 2013 Location: Des Moines IA Member`s Gallery Posts: 242	Granted I have a custom .83 housing on mine, but I see 45-50 PSI of boost on mine threw a 100psi sensor on my Edge. As said above, check for a exhaust leak or boost leak, you should have no problem breaking 600Hp with the above set up. __________________ 2001 Chevy Red on Black with stuff done to it.....

03-01-2019, 03:34 PM	#13
JWhite Name: JWhite Title: Trained monkey Status: Not Here Join Date: Aug 2009 Location: F Burg Ohio Member`s Gallery Posts: 1,817	Not sure what your 42% pump is, but I imagine it's a modded stock stroke setup. The most you'll see on those is around 600-625. You could give it more fuel and possibly pick up a few hp, but it would be on the ragged edge of losing rail pressure. I would put money on Rob set you up right __________________ GMC with a LiLLY

03-01-2019, 08:02 PM	#16
TheBac Name: TheBac Title: UPS guy Status: Not Here Join Date: Oct 2009 Location: Mid Michigan Member`s Gallery Posts: 2,344	Takes me back 10 years. Gotta love a crazy bastard trying to push 600+ thru an LB7. __________________ Tom "BBT" -- 2003 GMC CC/SB 4x4 12.14@111.15 "KLESHAY" -- 2000 C5 Corvette -- the toy 2017 Buick Regal 2.0T -- the DD

03-02-2019, 05:21 AM	#20
TheBac Name: TheBac Title: UPS guy Status: Not Here Join Date: Oct 2009 Location: Mid Michigan Member`s Gallery Posts: 2,344	Jwhite, I think he may be confusing running dual cp3s with running larger injectors, so he can turn down pulse and timing. Austin, LB7s like rail kept above 21000 at a minimum to keep from losing power. The higher the pressure you're able to maintain, the better. Otherwise turn timing and/or pulse down until you see you can maintain pressures. Larger injectors will help you keep timing and pulse reasonable, which helps immensely with keeping the spray pattern in the piston bowl, but they don't help with keeping rail pressure up at the same power level. If you go bigger injectors, I'd also do at minimum a 10mm cp3 or dual setup. Stock cp3 alone won't be able to keep up, and you'll simply lose power. Boy, those LB7 rods are going to hate you, if they aren't bent already. Have you done a compression test yet to check? __________________ Tom "BBT" -- 2003 GMC CC/SB 4x4 12.14@111.15 "KLESHAY" -- 2000 C5 Corvette -- the toy 2017 Buick Regal 2.0T -- the DD Last edited by TheBac; 03-02-2019 at 05:25 AM.