6.0 Conversion

Had a long take with my mechanic today and it looks like it if we got a 6.0 that was maybe an 06 or 08 (used) had a PCM set up for it from Nash I would be into it for around 8k. Not a bad price I think. Other than a alpha oil pan, alpha exhaust manifolds motor mounts, wiring harness, maybe an input shaft on the tranny; am I missing anything? Will a heavy duty L460 tranny bolt up the the Borg Warner case? Or a 480? Oh and alpha torsion bars. Wondering if my new OEM radiator will cool a 6.0? I'm going to start getting the necessary parts together. My mechanic said something about a 08 escalade being a 6.2 with 350 hp is we could find a smashed one.

dude.... :corn:

2007+ escalade had 403hp I think the newer ones are 420hp. For ease of getting this actually done just have your 4l65e professionally built to handle the power. I would just go with a 6.0 they are much cheaper, easy to find and can be easily built/ tuned to any power level of your liking. I looked into this a ton but had the 5 speed manual which makes the swap almost impossible

Sent from my HTC6525LVW using Tapatalk

Ty ATV! 420 hp seems a little over kill for a 3. Maybe I can get a few bucks out of my 3.5 with 86k it runs perfect but like everyone else says it's way under powered. So better clutches in my stock trans should hold it together with about 350 hp then?

If you have a choice 400 hp is nice to have, esp if ur running 35s/37s with gear. If the H3 diffs could be regeared, then this wldnt have been a discussion. Plus, The H3 is heavy!

For the transmission you will need a bell housing, input shaft and torque converter at a minimum to get it to bolt up. The pan, accumulator and I think the valve body are specific to the hummer to clear the front driveshaft so you may have to mix and match some pieces.

I am writing all this down, my mechanic sent Nash Motors an email for a price on the harness and PCM to correctly run the H3 electronics and a 6.0

From what I understand you may need to do some firewall work to get everything to fit, plus move the motor mounts. 08+ was built a bit differently at the firewall for clearance for the 5.3 - which itself seems a bit odd, since it would be a shorter block. Oh well, just relaying what's been passed down.

Sounds like a big project.

If you are really serious about this you need to start thinking in detail about every single subsystem. The cost of your engine will be only about half of your material cost. This does not factor in any labor costs for things you are not doing yourself.

I assume you are starting with an I5 and will use an alpha wiring harness and hardware during the conversion.

Examples:

Alternator : where is the new one located compared to the I5? new cables needed?

Starter: I5 is on driver side, standard chevy pattern is passenger side. New cables?

A/C. will alpha lines work, or custom hoses needed?

Fuel system: As far as I can tell the I5 is a returnless system. What lines need fabbing from the existing quick connect near the intake manifold to what you need?

Heater hoses. Alpha ones work?

Trans cooler lines: I5 are bent and formed to the block. Alpha lines or just run new hoses?

Power steering lines. Alpha lines or custom? Where is PS pump located on V8?

Transmission : discussed above to adapt.

Coolant hoses: Add to budget

Radiator shroud. Does fan center move and can you use existing?

All of this stuff will add up in $50 and $100 chunks real quick when either buying parts or fabbing something to work. You also have to figure your time in coming up with solutions to problems as they arise.

Plan on having a second vehicle to drive and take the time needed to solve each issue as it comes up. I would not recommend this if this is your daily driver and want/need to pull it off in a short period of time to get it back on the road.

Good luck and let me know if you need any other pointers.

While I have seen a 6.2L in a 2006 H3 without the firewall being touched, a 1" daystar bodylift would make things much easier.

Casey those things are being addressed by my mechanic. He's a hot rod fab kinda guy and if it sounds like it's going to be way off from 8k then I'll dig deeper. Thank you for bringing those things up though I suspect there will me even more hidden cost before I even start the project. I never ever thought for one second that something like this would be a complete plug and play upgrade................................

First off you can pick up a 6.0 for less then $1000 and if you wanted to go cheap I can get 5.3's for $500 sometimes as low as $250.

Why start by going cheaper on the motor? You can put a bunch of miles on them. Then at a later date the 6.0 or 6.2 would just be a bolt in swap with a minor change to the tune.

It's in a different vehicle but look up yates efi. He used to have a lot of good info into these gm motor swaps. These swaps are so common on other platforms there are plenty of harness options out there. Now he has never done a swap in a H3. But a swap is a swap.

Is there a reason you want to go with a 6.0? How much power are you trying to make? There are tons of 5.3s in junkyards which are cheaper and can easily make 400+ hp. it really depends on what you are trying to accomplish and your budget.

The reason I am thinking 6.0 is because externally it is the same size as a 5.3 with more standard HP is all. Plus I had a 6.0 in a 2002 Silverado HD and I liked the way it ran and towed. And most of them put out at least 300 hp.

go with the 6.0 - the 5.3 is a great motor for a light car, not a 6000 lb hummer. Torque is your friend

I could put out over 400 hp with a 5.3 and a cam swap. If you want power to go racing I can put a turbo system on a basically stock 5.3 and make 1200 hp. Just have to resize the ring gaps.

I agree 6.0's can be fairly cheap and a good motor to use. I put a 5.3 in a 91 3/4 ton Chevy with 4.10 gears and was getting 18 mpg. Did not even know my Camaro was behind it when towing.

This would be a fairly easy swap. I hope you go thru with this. I personally only feel the need for extra power if I'm towing something. But now that I got a 2500HD I don't hook anything behind the h3.

Gotta ask - what would you do to the 7.6" IFS to handle all that? I'm thinking its limitations would be exposed quickly with a massive torque/power increase.


Sent from my iPhone using Tapatalk

Why would anyone bother with a 5.3 swap when you can just trade up to an alpha?

The name of the game with a hummer is not peak hp numbers but power under the curve. If it were simple, there would be 5 different vendors with a "kit" on the market. My point was there is much more to an engine swap than just the engine and associated power adders if you are so inclined. its all the small integration details where the money adds up and makes the difference in something that looks like it belongs there or a total mess of hoses and wiring that becomes a perpetual project vehicle.

There's something to be said for pouring the money into a vehicle you know vs. buying used off of a lot. I know what's been fixed on my truck and how it's been maintained. I think that's likely the same reason that DesertH3 is putting some significant $ into putting a new 3.5 into his H3. Expensive, yes, but lower risk too.

I haven't decided what I'll do when my engine dies. I've talked the 5.3 and 6.0 but it's more likely I'll stay 3.7 just for the reasons that you indicate, Casey.

CaseyS said:

Why would anyone bother with a 5.3 swap when you can just trade up to an alpha?

The name of the game with a hummer is not peak hp numbers but power under the curve. If it were simple, there would be 5 different vendors with a "kit" on the market. My point was there is much more to an engine swap than just the engine and associated power adders if you are so inclined. its all the small integration details where the money adds up and makes the difference in something that looks like it belongs there or a total mess of hoses and wiring that becomes a perpetual project vehicle.

Click to expand...

because they want 4.56 gears?

For me, I hate vehicle payments. I don't have a payment on my 3. I retire in 4 years. I am keeping my 3 as my toy. A 6.0 conversion will make me happy. We don't do any rock crawling in Michigan. It's either mud or sand. I feel the drivetrain will hold up. Yes there may be little things that hinder this conversion costing more money. And I will address them as they come. When I do it I will post a build thread if you all want. For those of you that feel it just won't work don't read it. ..........

I wheel my truck pretty agressively with 35s on sand. I am yet to have any serious issue. I think most of the damage I had (upfront) was due to my backspacing rather than week parts! I say go big, Id like to see how this is going...

I work for the State of Michigan and they owe me almost 10k from making me pay 4% toward my retirement for the last couple years and the money is suppose to be returned soon so guess where it's going? Conversion cash!..............