To LS or not to LS, that is the question

stutaeng

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Just not a big fan of the 6.0L here, especially with those torque robbing rectangle ports on it. If I had a heavy truck or van with the rectangle port 6.0L in it like a LY6, my first swap would be a set of 862 heads ported by Lloyd Elliot with 2.00 intake valves and a Trailblazer SS or NBS 5.3 cathederal port manifold. Give it a nice shot in the arm in the low-midrange where you actually run 95% of the time. Why GM never put the 6.2L in the vans always baffled me. I always liked the 96-02 vans best, atleast in 96-2000 you could get the 454 and 01-02 you could get the 8.1. With those big blocks you could get 3.42 gears behind the 4L80E. GM had a higher tow rating on the 3.42 geared big block than the 4.10 geared small block. In the real world fuel economy was about the same but the big block had alot more get up and go.

Yes, the 8.1 vans seem like beasts. 10,000 lb towing capacity with the 4.10s. I saw a really nice one recently, but again, a LWB.

I DD an LQ4/4L80/4.10 in a suburban and have no complaints. I don't really even push it over 2500 RPM getting on the highway. Only once I towed one of those 6x12 U haul trailers around here. Probably was no more than 4,000# load though. My previous DD was an C1500 ECSB 4.3/4L60e/3.42 and I also have a K3500 CCLB 5.7/4L80e/4.10. I drove the 4.3 for like 10 years, so both the 5.7 and 6.0 are nicer to drive, even though they are heavier vehicles.

As to why the 6.2 was not offered on the Vans...My theory is that the aluminum block would have not stood up to the rigors of a heavy vehicle. Likewise, the 6.2L was not offered in the HD trucks. The power is there, but durability would of have suffered, in my opinion. Cast iron I believe is the material of choice for heavy GVWR. Note the 6.6 GM gas engine is iron block.
 
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Christian Steffen

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Would you really? The 6.6 is a new engine, and it's paired to the 6 speed. The 4.3 is paired to the 10 speed. I don't know the logic behind that but you know the vans are weird, LOL. And that's only on the 2021 models. Everything GM is now direct injected. I wish GM would have come come up with something similar to the Ford 7.3 gas engine.

I was looking at the '13-'19 range. Frankly, not finding a lot of standard wheelbase passenger vans. Most are cargo and the passenger vans seem to be extended wheelbase mostly. Think CCLB wheelbase, LOL.

GM should have just went bigger with the 6.6, hell the 6.6 is still very close to the 7.3 with its displacement handicap. DI has some downfalls (cost, maintenance, etc) but as far as performance is concerned it works really well. An actual big block, with LT head design, DI, & VVT would be amazing, but I'll quit dreaming.
 

L31MaxExpress

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GM should have just went bigger with the 6.6, hell the 6.6 is still very close to the 7.3 with its displacement handicap. DI has some downfalls (cost, maintenance, etc) but as far as performance is concerned it works really well. An actual big block, with LT head design, DI, & VVT would be amazing, but I'll quit dreaming.
Honestly I would rather have a PSI 8.8 with a hotter cam. In school bus trim they make like 565 ft/lbs @ 1,600 rpm and 270 hp @ 2,600.
 

L31MaxExpress

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Yes, the 8.1 vans seem like beasts. 10,000 lb towing capacity with the 4.10s. I saw a really nice one recently, but again, a LWB.

I DD an LQ4/4L80/4.10 in a suburban and have no complaints. I don't really even push it over 2500 RPM getting on the highway. Only once I towed one of those 6x12 U haul trailers around here. Probably was no more than 4,000# load though. My previous DD was an C1500 ECSB 4.3/4L60e/3.42 and I also have a K3500 CCLB 5.7/4L80e/4.10. I drove the 4.3 for like 10 years, so both the 5.7 and 6.0 are nicer to drive, even though they are heavier vehicles.

As to why the 6.2 was not offered on the Vans...My theory is that the aluminum block would have not stood up to the rigors of a heavy vehicle. Likewise, the 6.2L was not offered in the HD trucks. The power is there, but durability would of have suffered, in my opinion. Cast iron I believe is the material of choice for heavy GVWR. Note the 6.6 GM gas engine is iron block.

GM had some aluminum 6.0Ls in vans around 05-06. I have personally pulled 2 of them. Complete with LQ4 dished pistons. Aluminum block holds up every bit as well as a cast iron, maybe better. Aluminum is less prone to cracking from localized hot spotting. I think it merely boils down to cost.
 

kenh

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So..... It looks like there are two possible throttle bodies to use. A cable to the throttle plates much like our TBI units and a wired unit with no physical connection to the go fast peddle.

My question concerns the cruise control. With he cable unit, the cruise control needs to used as is and somehow hooked to the throttle body and also needs a signal from someplace.

Where doses the cruise gets it's signal from assuming I'll use the stock 700R4 (4L60) trans.

If I go with an "E" trans then where do I get the signal from?

If I use the drive by wire throttle body, is the factory (1990) cruse control even needed? I'm assuming the computer drives the throttle body to the correct speed????

AGAIN
Where doses the cruise gets it's signal from assuming I'll use the stock 700R4 (4L60) trans.

If I go with an "E" trans then where do I get the signal from? (I assume it all works with the computer so no muss no fuss????)

Thanks!

Ken
 

Anubis

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I also have a 1990 K1500. In my opinion the best way is to use the factory cruise control. The 5.3 I plan to swap in had a drive by wire throttle body which I’ve converted to cable operated. The cable operated throttlebody has provisions for the factory cruise control. Easy Peezy. If you plan on using your factory 700 R4 then no additional wiring is needed. The cruise module uses the VSS signal.
 

L31MaxExpress

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I also have a 1990 K1500. In my opinion the best way is to use the factory cruise control. The 5.3 I plan to swap in had a drive by wire throttle body which I’ve converted to cable operated. The cable operated throttlebody has provisions for the factory cruise control. Easy Peezy. If you plan on using your factory 700 R4 then no additional wiring is needed. The cruise module uses the VSS signal.
I am of the opposite opinon myself. I find the DBW easier. I did a DBW LQ4 swap in a fomerly 305 TBI 87 G20 van. I ended up using a pedal out of a chrysler hemi application. Electronically it matched with the 05 TAC module. Hooking up the cruise was a 3 wire connection and the 87 vans stock switch works. Even my 83 G20 had the same cruise switches. On/Off and momentary Set/Coast and Resume/Accelerate. Both the 83 and 87 vans also had a normally open and normally close brake switch too.

My 99 Tahoe has a DBW 8.1 in it. Pedal came from a GMT400 8.1 3500HD.

Even with 2.00 valve 862 heads ported my Lloyd Elliot that were milled 0.020", a mild cam, NBS intake manifold, headers and catless 2.5" exhaust with a X-pipe the 6.0L is a bit of a pooch until you really turn it into the RPMs. I left the TH400, added a VSS to the tailshaft and left the 3.08 gears. The 305 would haze the tires the 6.0L just kinda goes. 6.0L pulls harder up in the rpms but the 305 TBI had more low-end torque.
 
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Anubis

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The problem with going DBW is that only a few select ECM‘s will control the cruise. I also don’t want to have to butcher my cruise control wiring when The stock pull off module works just fine. Most newer ECM‘s that use CANBUS architecture will not control the cruise.
 
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