8.1 Vortec for the project.....

[SunSoaked]

Local Craigslist ad ....Hmmmm,,should I?

"I'm selling a 8.1 vortec running engine with 93,000 miles. Came out of a 2001 sierra 2500. $800 obo"

[69GWC]

I know that would end up in my 69, that would be a great project.. lol.

Plenty of lowend torque right there, got something to stick it in.?
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[DirtyLarry]

Originally Posted by SunSoaked

Local Craigslist ad ....Hmmmm,,should I?

"I'm selling a 8.1 vortec running engine with 93,000 miles. Came out of a 2001 sierra 2500. $800 obo"

That is a good deal, even though it is a filthy pig. You will like the L18! Nothing like having big HP and Torque in one package plus they are an easier swap than a cute little LS engine

You have a lot of work ahead of you though. Here are my recommendations:

- Remove the EGR valve and pipe to the exhaust manifold then obtain an EGR plate cover from a 2004-2010 8.1L. The EGR valve as it sits might interfere with the firewall, plus the valve and exhaust tube are just outright ugly.

- If you are running A/C, remove the front accessory brackets and replace them with 2001-2002 G-van, pieces in order to move the A/C compressor up high on the driver’s side. The A/C compressor on the Silverado/Sierra 8.1L in your picture will required unnecessary frame hacking. Don’t be that guy that hacks up a frame!

- Take the electric throttle body off and run as quickly as you can with it to the nearest trash can and drop it in there then replace it with a 1996-2000 L29 7.4L mechanic throttle body. The L29 TB will require a 1” TB spacer to allow room for the cable arm to swing. There is also a later model plastic engine cover and oil fill tube that moves oil fill further to the passenger’s side which allows room for the throttle cable to pass. Look at my 8.1L swap pictures in my signature to see what I am taking about.

- Remove the exhaust manifolds that are on it now and chuck them. They will not fit your frame without major hacking. The 8.1L will accept any exhaust manifold or header from any old big block. I run 80’s 454 manifolds on my 8.1L.

- Replace the Crank Sensor in the rear of the engine before you install it in the truck. Once it is in the truck, you will not have enough room to replace the CKP sensor. The engine in your picture is an early 8.1L with the horrible CKP design. Chances are it is not original and already replaced with the second design. To be safe, replace it again!

- Howell Engine Developments builds a great harness for an 8.1L as well as ECM tuning. Recommend tuning out the EGR Valve, Torque Management, and Electronic Throttle control. Their 8.1L hot tune is good for around 425HP/555 lb ft of torque as they told me when I did my 8.1L swap.

- The 8.1L you have is also an early one where it will have an adjustable fuel pressure regulator. Once it is running, bump the fuel pressure up to about 67-68 psi at idle. 8.1L's love higher fuel pressure over what is documented. Vrooommmm!!

As you get closer to fixing this thing up let me know as I have all of the part numbers you will need.

Hoping to get started on another 8.1L swap soon as well. This time the Polar Bear Burb is getting infused with one. I love that engine! IMHO, it is the best all around truck engine GM ever built. It pulls like a diesel but has hot rod horsepower too boot.

[DirtyLarry]

Whoops, looks like my L18 swap pictures are not in my signature anymore. Here you go.

I installed my L18 in 2008. The first year I ran it on a Delphi MEFI-4 ECM (Ramjet 502/Marine) with a tweaked marine calibration running speed density calculation. I did not like the way it ran so I converted it to a P59 ECM (typical GM ECM used on 2000-2006 GM vehicles) and Howell Harness with MAF. Much better! That said, you will see a small ECM and a tiny harness in the earlier pictures in the picture set. Those have been removed from the truck years ago.

[SunSoaked]

Dang Larry, that sounds like a lot of work and not much of a "drop in". I have a stand alone edelbrock pro-flo I was thinking of using on it. It's 1000cfm and edelbrock will burn me a new chip. From the basic tune on the chip, it's all adjustable from the control module.

Other than an intake/exhaust manifolds it should be plug and play. Only thing I'm not sure of is the coil packs. I don't know if the pro-flo will work with them.

This motor might be overkill for how I'm using the truck, but seeing that 8.1 locally for what seems like a decent price has got me thinking

[DirtyLarry]

Oh, boy… You won’t be putting an Edlebrock or any other intake on a L18 8.1L. The only intake that fits an L18 is what it was born with. The engine is similar to older big blocks but yet is entirely different, especially in the heads and intake. You can’t even swap heads form an older big block to an L18 as the water jackets and head bolts are entirely different plus the heads are taller. In fact, the intake is dry with no coolant passing through it at all and each head has 2 additional head bolts than older big blocks. Really, to do an L18 swap right it is a $1500 to $2500 date not including the acquisition cost of the engine itself. You better pass on this Craigslist deal and let someone else go after it

View of the differences in intake ports between older BB and the L18

[dieseldawg142]

Originally Posted by DirtyLarry

Oh, boy… You won’t be putting an Edlebrock or any other intake on a L18 8.1L. The only intake that fits an L18 is what it was born with. The engine is similar to older big blocks but yet is entirely different, especially in the heads and intake. You can’t even swap heads form an older big block to an L18 as the water jackets and head bolts are entirely different plus the heads are taller. In fact, the intake is dry with no coolant passing through it at all and each head has 2 additional head bolts than older big blocks. Really, to do an L18 swap right it is a $1500 to $2500 date not including the acquisition cost of the engine itself. You better pass on this Craigslist deal and let someone else go after it

View of the differences in intake ports between older BB and the L18

$1500-$2500? jeez, makes me wish i dropped that $3500 for my pro flo on an 8.1 swap instead!

[dieseldawg142]

just looked at your link larry, that is a super clean install! (little crowded with the a/c), idles nice too. that must be an absolute blast to drive. i got a b.block to ('85 454), i know mileage is'nt stellar with these engines, but what kind of mpg's does your 8.1 manage?

[DirtyLarry]

Originally Posted by dieseldawg142

$1500-$2500? jeez, makes me wish i dropped that $3500 for my pro flo on an 8.1 swap instead!

Wholly cow! There would be no way I would drop that kind of money on an aftermarket EFI system. I’ve messed with aftermarket EFI systems before and nobody builds a more durable system than GM Powertrain. With some slight tuning even a stock EFI system will run circles around aftermarket systems by loops and bounds. The aftermarket doesn’t put millions of test miles and thousands of test hours into their stuff like auto manufacturers do.

To your point, you are exactly right, $2,000 just to install one if these is small apples compared to other options out in the world. The biggest problem is most L18’s usually go for $2,000 on up just for the engine itself where as an LS small block goes for considerable less. $800 for this CL L18 is a really good deal. If it was closer I would snag it up in a second to add to the collection of other 8.1L’s laying around here.

Prepping to put this one in the Polar Bear Burb soon

[DirtyLarry]

Originally Posted by dieseldawg142

just looked at your link larry, that is a super clean install! (little crowded with the a/c), idles nice too. that must be an absolute blast to drive. i got a b.block to ('85 454), i know mileage is'nt stellar with these engines, but what kind of mpg's does your 8.1 manage?

Yeah, it is crowded under the hood with the Hickey Sidewinder winch controller, dual battery isolator, dual batteries and engine ECM then the bulky air induction pipe on top of all that. They do idle nice and smooth though. The change GM did to the firing order on LS engines and L18’s made a huge difference in how smooth they idle and run through all RPM ranges, exhaust sounds a bit odd though if you don’t run an equalization pipe though. The old Chevrolet V8 firing order was 1-8-4-3-6-5-7-2 while the new LS small blocks and L18 8.1L changed to 1-8-7-2-6-5-4-3. Hard to believe a firing order change makes such a noticeable difference.

I’ve only tracked fuel mileage once, last summer on a 1,500 mile off-roading trip to Utah and Western CO. I just kept track of the total gallons used compared to the miles driven and came up with 11.72 MPG. Not too bad for an entire trip bouncing through the Desert in 112 degree temps and climbing Imogene and Red Cone passes in 4 low on a truck with 35" tires, 4:56 gears and weights 8,000 lbs. with the aerodynamics of a drive in movie theatre screen. My stock Silverado HD does about the same empty. Best tank it ever got was 13 MPH driving to Albuquerque once, probably would have been better had I not been going 85 MPH

I will say this though; L18’s drink oil and coolant. My stock Silverado that only has 55K on it has drank 1 quart of oil every 1,200 to 1,500 miles since the day I brought it home when it was new. On the other hand, the K10 doesn’t use a drop between 3,000 oil changes but it drinks up coolant. Both oil and coolant usage are common complaints with RV owners that run L18’s in big motorhomes but the usage is considered normal for a big block engine per GM Powertrain.

[dieseldawg142]

yes, agreed. the stock TBI in my stepside has 250k with 1 rebuild. the pro flo(gen 1) was my first foray into EFI (back in the 90's), there was'ent much around then & our dollar was just brutal back then, 65 cents to the american buck. since it was what i had, i spent more & upgraded to gen 2 a few years ago.
still, even 5 g's for a 8.1 swap is a heck of a deal for what your getting. everyday driveability & enough torque to haul your stuff & still embarass most cars on the road

[SunSoaked]

My pro-flo works great and I am very happy with it on the 350 I have sitting in the garage. In fact, I'm going to run this engine in the truck until I work out all the bugs (I'm starting from scratch-drivetrain, wiring, etc). My plan was to swap the pro-flo onto a 6.0 Vortec. I want some fuel mileage and will rarely be hauling/pulling anything that needs a 8.1 under the hood.

Larry-regarding the firing order on the LS motors; at the risk of looking stupid, when did the "LS" series start and more to the point are the Vortec
6.0s LS engines? If so, I guess I'll be switching the firing order back to the "old" style, if I'm gonna use my FI.

Thanks for the input Larry. Your knowledge once again kept me from going down the wrong path

[DirtyLarry]

Oh, yeah. I remember when the Canadian dollar was pretty weak. That was a brutal time for Canadians. I lived in Detroit or a few years and crossed over to Windsor often. At that time it was 1.40 to 1.00 American.

Interesting facts on the L18 8.1L. GM stopped using it on the Silverado/Sierra platform at the end of the GMT800 run in 2007 although the 8.1L soldered on in the GM medium duty trucks until 2009 when GM went bankrupt and put the kibosh on medium duty. That still wasn’t the end, as Workhorse Custom Chassis continued with the L18 up through the beginning of the 2011 Calendar year while still building 2010 model year chassis. Actual production of the GM Powertrain L18, as well as the big block legacy, stopped production at the Tonawanda, NY engine plant on 12-18-09. Tonawanda built a huge stock pile of engines before actual vehicle production stopped.

But wait….there is more, it doesn’t end there. A company called Power Solutions International has purchased the production rights of the L18 big block from GM and are manufacturing the engine now for industrial power applications (generators, etc.), on-road (other RV chassis manufacturers such as Spartan Chassis, as well as heavy duty on-road vehicles. I don’t believe PSI has landed an OEM truck manufacturer for the engine yet although Freightliner and Navistar are both candidates to offer the big gas power plant in their medium duty vocational trucks. PSI offers still offers it in 8.1L in the same form as GM did as well as an 8.8L version that is emissions certified for 430 HP/514 lb. ft. of torque at 3,400 RPM. I predict there will be a direct injected version in the next few years with crazy HP and torque numbers as well as fuel economy that will make a diesel engines much less desirable in medium duty applications where diesels have usually ruled the roost.

Here is a rare peek at the last of the GM production intent L18’s. Believe me, I darn near licked the valve cover of each of these engines before I walked away with a tear in my eye

[DirtyLarry]

Originally Posted by SunSoaked

My pro-flo works great and I am very happy with it on the 350 I have sitting in the garage. In fact, I'm going to run this engine in the truck until I work out all the bugs (I'm starting from scratch-drivetrain, wiring, etc). My plan was to swap the pro-flo onto a 6.0 Vortec. I want some fuel mileage and will rarely be hauling/pulling anything that needs a 8.1 under the hood.

Larry-regarding the firing order on the LS motors; at the risk of looking stupid, when did the "LS" series start and more to the point are the Vortec
6.0s LS engines? If so, I guess I'll be switching the firing order back to the "old" style, if I'm gonna use my FI.

Thanks for the input Larry. Your knowledge once again kept me from going down the wrong path

I don’t see a Pro-Flo working for you on anything other than an old SBC due to the design of it. The 1999 (back to 1997 if you count the 5.7L LS engines in the F and Y body cars) LS engines are entirely different than the old SBC we have enjoyed since 1955. The 6.0L was first offered in the 1999 model year when the New GMT800 Silverado (Remember “The Truck” campaign with Kap Ripkin?) and Sierra. Sounds like you need to come to a decision if you want to use this Pro-Flo thing you keep bringing up or step up and just use an LS engine (or L18 8.1L) with its original designed fuel system. I would pimp the Pro-Flo thing on CL and buy the 8.1L!

[Zoomad75]

Go with the 8.1. There is NO replacement for displacement. Look at it this way, the 8.1 used in the RV was pulling rigs with GVW's of 24,000 to 26,000 pounds. I've driven many of them in the mountains loaded at or near GVW and pulled up 6%+ grades at the speed limit. They pull like a locomotive. It's darn near bulletproof as long as you keep an eye on the fluids like Larry said. We replaced 3 RV 8.1's at our shop 2 summers ago common point of failure was lack of coolant causing them to overheat and cook themselves to death. Had they just kept an eye on it I wouldn't have had to replace them.

I've commented before about how Larry's truck runs with the 8.1. Let's just say the truck goes faster that anything that big should. That's coming from me seeing his tailights disappear up the hill in front of me and my wheezy 350 trying to keep up with him. Riding shotgun I've seen him pass cars accelerating from 65 to 75 without ever downshifting. On the flip side, the 8.1 has so much torque down low it can idle over just about any thing he comes up to off road. It's about as close to having your cake and eating it too you can get. You could say Larry eats a lot of cake. It's a wonder he isn't a big guy like me!

8.1's aren't the cheapest to swap but probably are the best kept secret for brute power/torque without all the issues of going to a diesel. No 6.0 LS engine can build this kind of power without a lot of help and still do it so low in the RPM band. That's where the big displacement really shines.

[dieseldawg142]

man larry, where do you get those pic's!? for the want of just one of them 8.1. it would be perfect in my 4 ton honey

[DirtyLarry]

Originally Posted by dieseldawg142

man larry, where do you get those pic's!? for the want of just one of them 8.1. it would be perfect in my 4 ton honey

Can’t say but, we’ll just say I went down to the factory and snapped a few pictures myself.

[Zoomad75]

Originally Posted by DirtyLarry

Can’t say but, we’ll just say I went down to the factory and snapped a few pictures myself.

Nice Johnny Cash reference!

[DirtyLarry]

Originally Posted by Zoomad75

Nice Johnny Cash reference!

Ya, hehe.....Johnny was the first thing that came to mind on this topic Wasn't sure anybody would make the "Piece At a Time" connection with that statement.

[Mr. 250r]

I would be extremely careful with that buy since there is no way of testing it.... but just personal preference i guess
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[OrrieG]

Originally Posted by Mr. 250r

I would be extremely careful with that buy since there is no way of testing it.... but just personal preference i guess
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First question that came to my mind was why was it pulled?? Larry thanks for all the information on the 8.1 engine and swap. I have never had anything except for carburated 350 and earlier SBC, did not want the potential problems with electronic motors. But I am also dragging a 69 C30 dually back from Oregon that intended use might be a travel trailer hauler when I retire. The 8.1 sound like it might just be the engine to use.

[ryanroo]

all this talk has me really considering an L18 for my jeep now. it has an old TBI 454 but id love to step up. ive been idly toying with a 6BT swap, but i do like my BBC... plus, i dont need no stinkin a/c, and already have some headers that work.

do the taller heads equal taller overall height? it looks like a shorter VC is used. that is my biggest clearance issue in the M715

[DirtyLarry]

Originally Posted by ryanroo

all this talk has me really considering an L18 for my jeep now. it has an old TBI 454 but id love to step up. ive been idly toying with a 6BT swap, but i do like my BBC... plus, i dont need no stinkin a/c, and already have some headers that work.

do the taller heads equal taller overall height? it looks like a shorter VC is used. that is my biggest clearance issue in the M715

Heck ya, go for it! It is a lot easier swap than a Cummins and you would have more power than an old 12V Cummins without the crazy amount of weight over the front axle, stench of diesel and the brain rattling noise. The only thing you wouldn't get is 20 MPG

Correct, the valve cover is actually shorter so the overall height is the same as older big blocks. Dimensionally, it is same footprint as the L29 Vortec 7.4L it replaced.

Here are some poorly scanned engineering dimensions. The dimensions are in metric. This is a Silverado/Sierra application so the accessory brackets are not the same I use.

[SunSoaked]

For the record, the Edelbrock Pro-Flo uses all GM Parts except for the manifold which is as good or better than the GM unit (GM probably sourced it from an aftermarket OE anyway).

I can buy any piece of it from any local parts store. Durability wise, I can't see an OE system being any better than the Pro-Flo.

Everybody has brand sentimental to some extent.

[SunSoaked]

And...

I want a daily driver that I can afford to put fuel in. I'm not looking to pull an 8000 lb trailer over the pass as I blow by the winnebagos .

Yes, I agree bigger is better-if thats all that matters. These guys that brag about getting 10 MPG with thier 454's must have more cash laying around than I do.