ach1992880

I have been driving my 71 cutlass with a cammed 6.0 for a couple years now sparingly while working all of the kinks out. Finally got it to a local dyno shop for a tune and had it properly tuned. I didnt know what i was missing! They found 62hp and over 30 ft/lb torque through the tune on a mustang dyno. The numbers arent overwhelming, but it runs and drives amazingly. Final numbers were 403hp and 387tq on the chassis dyno. My smile is a mile wide. Gonnna be a good summer!

csouth

Very nice! Was that an LQ4?

ach1992880

Originally put in a 155k mile 2002 LQ9 but the cam bearings were shot. Bought a .030 over 6.0 iron short block with flat tops to replace it. Going to keep the old LQ9 and have it tanked and new cam bearings installed for the next project.

csouth

OK. sounds like it will be fun paired with the right heads.

ach1992880

It already has Advanced induction 226cc cnc ported 243's on it. The cam is a pretty mild 227/232 with around .580 lift and i am running stock truck intake and throttle body. Running full length 1 3/4" dougs headers. Thinking the intake and tb are choking me down but i am done spending $$ for now and am going to do some driving.

csouth

Very nice... I have some spare 243's I'm sending to TEA now for porting. It may be the TB more than the intake. Truck intakes can make good power, its just more designed for torque. The TB would be the choke point I imagine.

ach1992880

My thoughts exactly. My problem is that my tb is a 2002 one year only style dbw. I would have to rework my harness if i got a bigger tb. Also, I passed up an LSXRT intake a couple years ago for $450 and have been kicking myself ever since. The car is a cruiser, never going to see a track, so not all that important to get the biggest numbers. Right now i am trying to keep the mindset that i am close enough even if there are 30 or so more hp available.

csouth

Its tough when you miss deals like that. I had no immediate plans to change my intake, but a LSXr cam up for sale on LS1tech for $550. I bought it and sold my stocker for $250, it wasn't a bad deal at all for me.

I think porting and polishing the TB may improve throttle response

bigrbandit

How well does the truck intake clear the hood? What mounts did you use? Headers or factory truck exhaust? Front acc drive? The cheapest I have seen is ICT billet for the AC mount, and stock truck Alt and PS mounts. I have a 72 cutlass and am thinking about a stockish 6.0.

ach1992880

The truck intake clears the hood without any problems. I used UMI Performance engine mounts after trying 2 different options that didn't work out. These mounts set the engine low giving better driveline angles as well. I did have to cut, flip, and re-weld the trans mount pad on the crossmember. I am using the stock truck accessory drive and currently do not have an A/C pump mounted. I will be going high mount on passenger side when I do that. My headers are Doug's ceramic coated full length and they fit great and tuck up tight to the floorpan giving excellent ground clearance.

Greaser007

I just bought my first 6.0L powered 2007 Suburban 2500 4x4 a year and a half ago with the clock at 70k. I know nothing about the L-series engines. Nor could I explain what a Vortec is. What I do know is that the 6.0L was found in the 2500 series light trucks ?
I have heard that some years had different fuel management systems to avoid. I am not on-the-know

Question: what are 243 heads ?

thanks,

Len

csouth

Vortec is just what they called the LS motors found in the trucks. 243 is the casting number for the heads found on LS2/LS6 and some 5.3 motors. They were the best flowing of the cathedral ported heads. Your motor will likely have 317 castings.
If you have questions, I would suggest starting a new thread just so it gets attention.

Greaser007

Chris,
thanks for the tip.
I enjoy reading through these threads to learn from you folks working with this stuff.

70cutty

What oil pan did you use for your swap?? My 463 is coming out and getting replaced by LQ4/4l80E.

ach1992880

I used the Holley 302-2 pan in my swap.

70cutty

Thank you!! I sent you a PM.

ach1992880

Replied to PM.

Aceshigh

Not one single picture ??

Congrats on complettion. I've still not completely finalized my massive overhaul. LoL
I had to go backwards and change out all my mounts to the Hooker swap kit to get the right driveline angles.

400hp SAE is quite respectable when you're talking you're comparing it to the classics which were 370hp / 500tq Gross.
When you do the conversion from Gross to SAE it's close, and yes some simple cam swaps will get you alot higher

ach1992880

LS engines really aren't all that much to look at, but this is how she looks just popping the hood this morning.

ach1992880

I am currently chasing a persistant header leak that is driving me mad. I thought I had valvetrain noise, but after 2 different engines with 3 different sets of lifters and 3 pushrod lengths for slightly different preload, I have determined that what I am hearing is a faint exhaust leak. The Doug's headers dont have a fully flat flange, but rather a raised port on the head side for each tube. I have filed them all flat with each other and tried a few different gaskets but just cant get a good seal. New headers are likely in my near futire.

This year I had a new exhaust put on the car to quiet it down and am happy with the result. It used to have some magnaflow knock off mufflers that were old and had all of the packing burned out. Sounded great at idle but was very loud at anything over half throttle. I went full 2.5" duals with 20" Dynomax super turbos and an H pipe. Still sounds nice, but so much quieter getting on it. i am very happy and dont feel that I lost any appreciable power.

beyond that, I am tossing around ideas to enclose my "hot air" intake and pull air from outside the engine bay. One thought I had was getting some '69 W30 scoops for under the bumper and using them to feed a stock truck airbox mounted in the current location. I can really tell when my air intake temps go up moving slow on a hot day.

Those are my only two complaints right now and really dont affect my ability to drive the car.

70cutty

Looks great man. Is that a shaved truck intake?

I'm almost done with mine. I used Holley everything for the swap, it made things very easy.

ach1992880

Yeah, shaved stock truck intake. Guy local to me used to do them for $100.

If I had done everything today I would have used nothing but Holley swap parts. When I did this that wasn't an option, making the trial and error process pretty awful. My angles werent half bad, but due to the lowered stance I still had to have a custom $900 CV joint driveshaft made to get rid of vibrations over 60mph. Smooth sailing now though.

Looks like you have a good start to yours. Good luck with the rest of the build.