47-55.1 Advise from LS swappers.

[whitedog76]

So, on my long-term 54, my plans have always been to swap in a Vortec 4200. Well, I sold my 04 Trailblazer last week to a young guy that did some insulating work for me. I've owned the Trailblazer since 05 and it was a great running vehicle for the last 200,000 + miles.

Anyhow, I'm looking to purge some of my remaining Vortec 4200 parts that I've collected.

First off, is the AR5/MA5 transmission worth bolting to an LS with the Fabbott kit? I already have
the AR5 and a LS 4l60e, which I bought for the 2wd tailshaft.

I also have a P10 ecm and an E67 ecm that are for the 4200, but are they worth keeping for the LS? The P10 is capable or controlling a 4l60e and it has an internal TAC control. I know the E67 needs a 58 tooth reluctor, but is it worth reflashing?

Last question, I can find Suburbans and old service vans for cheap, pretty much everywhere. Am I better off with a complete vehicle?

[mongocanfly]

My opinion..
Get a complete setup..
Sell the parts you have
It's not worth the aggravation of trying to piece it together..

[Accelo]

The number one rule. Purchase complete engine/trans/computer.

[whitedog76]

I was holding onto my Trailblazer, because it was a complete running vehicle, that I knew 100% of the history on. It sat out here for close to 4 years as a yard ornament. Someone came along that wanted it, well money talks...

Anyhow, it has kind of freed up some capital for me to do some mods that I wanted to do anyway, like a smooth firewall and C5 front spindles. So, passing the TB down the road isn't a bad thing.

I'm leaning more towards the retired service van route when the time comes. I would however like to use the AR5, so maybe a 4.8 might be the ticket.

[joedoh]

get an LS4. problem solved (well except the backwards intake) but easier than an adapter and LS4 are downright cheap for what they are

[e015475]

Just my 2 cents-

The LS motor's intake is symmetrical so as far as I know you can turn it forwards or backwards. I had an LS1 in a off road car and the intake was to the back of the car and it worked fine. You'd probably need to make some wiring harness changes to get the injectors in the right places along with the MAP sensor

The LS4 has an accessory drive that's unique to the transverse mounting and I'm wondering how it'd fit. It also says on the interwebs that the bell housing bolt pattern is "GM V6" so that might be a problem, IDK. The starter mounts on the transmission at about 10 oclock, not the low on the motor like most LS engines, so there's that too.

That said, there's conversion cars running around with LS4s and six-speeds, so it can be done.

[e015475]

First off, is the AR5/MA5 transmission worth bolting to an LS with the Fabbott kit? I already have the AR5 and a LS 4l60e, which I bought for the 2wd tailshaft.

Everything I see on the AR5 says the gear shift says the gear shift lever is about 24" back from the bell housing flange on the motor. I measured my truck this morning and the edge of the seat is 18" back from the bell housing, so to use an AR5 I'd have to ditch my bench seat and go with buckets. Do you have a solution to get the lever further forward? Is the AR5 out of a Colorado? If so, are you going to be happy with the gear splits with a low first gear? You might be ok with a numerically low rear diff ratio.

I also have a P10 ecm and an E67 ecm that are for the 4200, but are they worth keeping for the LS? The P10 is capable or controlling a 4l60e and it has an internal TAC control. I know the E67 needs a 58 tooth reluctor, but is it worth reflashing?

Truck & Suburban PCMs are cheap at the Pick and Pull. TAC modules and pedals too. It is very easy to get the VATs deleted and setup for your motor and is a well trodden path. Why would you want to start a science project trying to adapt an E67? Sounds to me like you have a truck to build. (Not trying to be a smartass - I've fallen into this trap many times)

Last question, I can find Suburbans and old service vans for cheap, pretty much everywhere. Am I better off with a complete vehicle?

4.8s and 5.3s are ubiquitous and cheap - you can't hardly throw a dead cat in a junkyard without hitting one. I'd just buy one. You've got the advantage back east where the trucks rust out before the motors are shot. I might jump at a complete vehicle if it were 6L and something special, but too much grief and hassle to drag stuff home and part them out. You've got a truck to build, remember?

The aluminum 5.3L out of Trailblazer makes a nice engine. Here's mine - pan, accessory drive, harness and PCM out of a Suburban. Intake from an LS1.

[joedoh]

Originally Posted by e015475

It also says on the interwebs that the bell housing bolt pattern is "GM V6" so that might be a problem

the AR5 and the LS4 have the bellhousing pattern of a 60 degree V6 (2.8 3.4 etc). the 4.3 was a 90 degree V6 like the SBC/LS variants. the ls4 does not have the ability to reverse the intake though, sadly.

i also didnt know about the starter position. problem unsolved haha

[whitedog76]

Originally Posted by e015475

First off, is the AR5/MA5 transmission worth bolting to an LS with the Fabbott kit? I already have the AR5 and a LS 4l60e, which I bought for the 2wd tailshaft.

Everything I see on the AR5 says the gear shift says the gear shift lever is about 24" back from the bell housing flange on the motor. I measured my truck this morning and the edge of the seat is 18" back from the bell housing, so to use an AR5 I'd have to ditch my bench seat and go with buckets. Do you have a solution to get the lever further forward? Is the AR5 out of a Colorado? If so, are you going to be happy with the gear splits with a low first gear? You might be ok with a numerically low rear diff ratio.

I also have a P10 ecm and an E67 ecm that are for the 4200, but are they worth keeping for the LS? The P10 is capable or controlling a 4l60e and it has an internal TAC control. I know the E67 needs a 58 tooth reluctor, but is it worth reflashing?

Truck & Suburban PCMs are cheap at the Pick and Pull. TAC modules and pedals too. It is very easy to get the VATs deleted and setup for your motor and is a well trodden path. Why would you want to start a science project trying to adapt an E67? Sounds to me like you have a truck to build. (Not trying to be a smartass - I've fallen into this trap many times)

Last question, I can find Suburbans and old service vans for cheap, pretty much everywhere. Am I better off with a complete vehicle?

4.8s and 5.3s are ubiquitous and cheap - you can't hardly throw a dead cat in a junkyard without hitting one. I'd just buy one. You've got the advantage back east where the trucks rust out before the motors are shot. I might jump at a complete vehicle if it were 6L and something special, but too much grief and hassle to drag stuff home and part them out. You've got a truck to build, remember?

The aluminum 5.3L out of Trailblazer makes a nice engine. Here's mine - pan, accessory drive, harness and PCM out of a Suburban. Intake from an LS1.

You are correct, the AR5 is 24" back from the bell. I have a thrashed 4200 that I bought for mock up purposes. Anyhow, the shifter comes up at the rear of trans cover in the floorboard. It would work with a factory bench, but would need an offset stick if you plan on moving the seat. I actually have my eye on some leather buckets from a Honda Pilot at the pick a part. I like the aesthetics of an original bench seat, which mine is in good shape, but it's not entirely necessary.

I do work in the construction industry. While the company I work for doesn't use Express & Savana vans, I know plenty that do. So coming across one is fairly easy.

You are correct in saying I have a truck to built first. I don't really have any plans on jumping on the LS train right now anyway. It's kind of a relief stepping away from the 4200, so I can focus on getting the truck built, not building the truck around the engine. I've had a bunch of different engines and drivetrains roll here through the years. Right now, I'm going to focus on getting the cab rust taken care of, buttoning up the MII front end, and finally getting rid of the remaining HO52. I'm still in the planning stage, got a million steps to go before an engine.

[mobileortho]

Originally Posted by mongocanfly

My opinion..
Get a complete setup..
Sell the parts you have
It's not worth the aggravation of trying to piece it together..

That's so true!!! Speaking from experience, it will nickel & dime you to death!!

[dsraven]

without getting into what else you need for your project, steering columns, seats, fuel systems etc, I would say buy a complete running vehicle with the engine and trans you want. pay attention to the oil pan and intake as well as the accy drive to ensure you will get something useable in your project. a truck set up will at least need the oil pan swapped or it will likely be too deep. that means pan, baffle, oil pump pick up and dipstick rube with dipstick at minimum. you maybe wanna look at a camaro, thats what a lot of guys are using for the oil pan, exhaust manifolds,, engine mounts etc. the left over camaro parts may be more sellable than truck parts, to help recover some costs, but will be more spendy to start with so you gotta weigh the options. look at copart or other insurance auctions for some deals. there is a bunch of info on different oil pans etc on the bellavista site-pirate 4x4 tech section. explaining the timeline differences on the lineage and cooling systems etc etc.

[dsraven]

build the truck with different engine and trans options in mind if possible.
I am building a 57 with a 4.2, its long. have used a 4.8 before, same dimensions as any other LS, needed to notch the firewall for extra engine width to place engine low and rearward. sbc came stock in a TF truck so that would be easy to say it fits-maybe not exactly where you want it to but it fits.
think big block fitment and then anything would fit, lol.
when building the chassis think of what else needs to go under there, exhaust, fuel lines, fuel tank, susoension etc. sometimes guy's builds get pretty tight at the rear axle or require side dump exhausts or holes cut through the custom frame for exhaust pipes. also, steering column and exhaust manifold clearances etc.

[whitedog76]

I actually mocked up the 4200 and AR5 in the chassis, with the solid axle. I had about 1/2 clearance on the front sump oil pan. So, I knew the oil pan needed modified. On the firewall, everything was good, some notching/hammer work to clear the intake.

With the MII, I installed it 1 1/4" lower in the chassis than what it was intended. The oil pan would still need modified, maybe even the crossmember notched slightly. I also welded nuts to the backside of the boxing plates so I could remove the engine mounts for easy in and easy out. I have Pro-Touring spindles with reversible tie rod brackets. I'm not 100% sold on them though. I really like the looks of the CS spindle and brake setup that CPP came out with a couple years ago. It basically uses C5 equipment on MII ifs.

I like looks of the small setback firewall from Absolute or Direct Sheet Metal, so that may be the direction I go. However, I have saved a 5 cu.ft. wheelbarrow also, so that may be something I explore too when I dig into the sheet metal process.

I think I'm off to a good start, I just need re-focus on what needs done.

[dsraven]

firewall- remember to leave footroom and accell pedal room. nothing worse than an uncomfortable position on a longer ride. leg cramps etc. my wife has an older audi tt convertible. it has a cramped footwell and a console with a brace where your calf would normally like to be. it leaves you wanting to get out for a stretch every hour of driving. I have seen some builds where the accel pedal looks like an afterthought and is very cramped due to the plan being more concentrated on getting the firewall done and worrying about the other stuff later.

[whitedog76]

My Transit and Transit Connect work vans are plenty cramped, trust me, I know the quality of leg room.

I bought a TJ and Express pedal assemblies, I never could get the Jeep pedals in a position that I liked. At least with the factory firewall. With the smooth firewall, it may be a different story. The Express pedal was a hydroboost unit, it actually fit great. I don't know how it'll be with an LS though.

My factory seat is in great shape, but I've spotted Honda Pilot seat at the U pull, that I really like. If I do the Pilot seats, I'll probably cut out the floor dip and put flat sheet metal in. I'm also open to the idea of a small floor hump, so the pilot seats might not be a big deal.

Just thinking and thinking...