[PAUL K]

Originally Posted by Jay S

I am late to the party, but here are some comments regarding the LS and Pontiac comparison. To me the performance Gap between the Pontiac based designs and the LS engine is slowing being reeled in. Turbo or N/A. Just comparing a ls 6 liter to a 400 is not using a Pontiacs attributes very well, with the same cam and cid the LS will handily beat the Pontiac. But the Pontiac has about a 1 inch taller deck than a std LS engine. Unless it is some sort of cid restrict class racing, use the CID to your advantages. Especially on a NA engine.

Here is on good example. Richard Guido out of Alberta canada runs a 515 cid turbo gto, he drives to and in Hot Rod drag week. Sometimes the trip is 2000 miles one way. I do not remember the exact mpg he average. But if I recall it was around 21-23 mpg. Unleashed IRC, it is capable of a lot of hp. Each year he seems to find more.

https://m.facebook.com/1320Videos/po...56578262167112

For a long long time I assumed big cid automatically meant gas guzzler. I no longer think that. Maybe there is a price for being big in town. Out on the open road we get in the low 20s mpg with 500+ Cid cars, no EFI, no overdrive.

Pontiac never had a MPFI system. That is one big reason you can go to a junkyard and pick up a LS in good shape, versus the Pontiac at the same miles is shot. I have a Yukon XL 6 liter about to 340,000 miles, still chugging along. They are great engines. I understand why people do the low dollar swaps. I consider doing a 6.0 swap in my 71 Chevelle, until I saw a LS in someone’s GTO years back. There is just something about classic muscle cars that the LS swap misses the mark. Put it in your 3rd gen firebird, fox body, street rod or pickup. LS is cool.. I put a 455 Olds in it years go for the same reason people do LS swaps now. Low budget, use what I have or can find.

FWIW, I have gotten right at 29.7 highway 200 mile round trip with a 5.9 Cummins in a 4x4 2003 extended cab pickup. It has about as many miles as my Yukon. Yukon best ever mpg is 16.5. 97 dodge dually 5 speed w/Cummins fuel up to about the same hp 350 or so gets 15-17mpg. 97 dodge has been one tough truck. My wifes magnum r/t awd with a hopped up 5.7 hemi gets low 20s. About the same as my 69 charger 510 cid with 3.23s.

Great post but I think things have been derailed. We're now on the "who has the best tow vehicle" part ...but I'm seeing things the same way you are.

[i82much]

Originally Posted by PAUL K

Great post but I think things have been derailed. We're now on the "who has the best tow vehicle" part ...but I'm seeing things the same way you are.

I say instead of talking about transplanting LS engines from trucks into Pontiacs, we talk about transplanting Pontiacs into trucks!

[Cliff R]

"My truck will downshift to second gear and fly up to around 5 grand on hills occasionally. But it just stays there very briefly, gains speed, and upshifts."

Unacceptable for a heavy duty towing vehicle gas, diesel or otherwise.....IMHO. If the engine can't pull it's own in the 3000-4000rpm's range with heavy loads on steep grades it's not up to the task. Not being able to keep it from doing that 3-4 gear downshift deal doesn't cut it for me, when I select the "manual" mode the ECM shouldn't go ahead and seek lower gears then "buzz" the engine in my $60,000 truck to and past 5000rpms. Doesn't matter how well it's made or designed that kind of RPM isn't cutting it for me and it can't be good for the engine in the big scheme of things.....IMHO

"The surging and the transmission lugging and then all of a sudden downshifting with the grace of a buffalo in a china shop is annoying."

Excellent description and the dealership thought that deal was perfectly fine. I tell everyone I know about it even if some folks on these Forums get their panties all wadded up about getting a little off-topic. The general public needs to know the good and bad points of these vehicles before going out and paying more for one than I paid for my last house!.......FWIW.......Cliff

[PAUL K]

Originally Posted by Cliff R

Excellent description and the dealership thought that deal was perfectly fine. I tell everyone I know about it even if some folks on these Forums get their panties all wadded up about getting a little off-topic. The general public needs to know the good and bad points of these vehicles before going out and paying more for one than I paid for my last house!.......FWIW.......Cliff

Sounds to me like you have a truck to roll down the hill behind your shop.

The OP got his answer in post #35

I definitely could careless how derailed any thread gets, but I do find it amusing how many issues there are with tow vehicles in the street section.

I also find it annoying how our GM vehicles hunt for a gear when towing up and down a grade. My brother solved his by wiring a switch into the system to keep that from happening. I solved the issue by putting the shifter in "D" when towing in an area with a lot of hills...FWIW

[PAUL K]

Originally Posted by i82much

I say instead of talking about transplanting LS engines from trucks into Pontiacs, we talk about transplanting Pontiacs into trucks!

A 455 would make a heck of a tow engine! TH400 and a 3:08 gear with no need for over drive... We would need to start a thread to determine the best compression ratio and whether a 041 w/ Rhoades lifters should be used or an OF cam.

[JSchmitz]

Originally Posted by Cliff R

"My truck will downshift to second gear and fly up to around 5 grand on hills occasionally. But it just stays there very briefly, gains speed, and upshifts."

Unacceptable for a heavy duty towing vehicle gas, diesel or otherwise.....IMHO. If the engine can't pull it's own in the 3000-4000rpm's range with heavy loads on steep grades it's not up to the task. Not being able to keep it from doing that 3-4 gear downshift deal doesn't cut it for me, when I select the "manual" mode the ECM shouldn't go ahead and seek lower gears then "buzz" the engine in my $60,000 truck to and past 5000rpms. Doesn't matter how well it's made or designed that kind of RPM isn't cutting it for me and it can't be good for the engine in the big scheme of things.....IMHO

"The surging and the transmission lugging and then all of a sudden downshifting with the grace of a buffalo in a china shop is annoying."

Excellent description and the dealership thought that deal was perfectly fine. I tell everyone I know about it even if some folks on these Forums get their panties all wadded up about getting a little off-topic. The general public needs to know the good and bad points of these vehicles before going out and paying more for one than I paid for my last house!.......FWIW.......Cliff

My truck works perfectly fine. It does everything I need it to.

I understand. Your truck is perfect (of course) and everyone else's is $h!t. Just like everything you discuss.

"I'm liking my 2018 Silverado with the 5.3 LS engine. Does everything I want and no problems whatsoever anyplace."

Someone else's truck:

"The truck was fantastic on flat ground"

"I wasn't the least bit impressed with the 6.0 HD set-up anyplace. "

Which is it?

[Half-Inch Stud]

Application-specific!
So, for best Towing, i suppose a Continental Aircraft 4 CYL is best for towing, maybe Lycoming. Just er ah 4L80, an ECM you like and 2" 4:1 Header.

My 95 Lincoln(s) seem to tow Class III very well for MPG & comfort. Becomes a laugh, not a pucker when i hit WV mountains: see the engine has limiter power, and i can find the peak TQ Converter TQ multiplier, butt hay everyone else can see the little engine that could so they pass happily rather than angrily.

Oh i've dreamer of putting a PMD 455 in the 95 Lincoln and grafting the EFI, & O2, & Coil Plates. Reuse the 4R70W & Converter as-is. Big-Stroke & Low RPM is my idea of MPG & Towing.

5000 RPM pucker-climb is real (U-Haul Trucks). Us Drivers putting all our car enthusiast faith into "i guess the designer(s) assumed the valvetrain can do this awhile". Bad MPG for any load or "hauling sailboat fuel"

LS....Im afraid of the ECM Reliability; those LS vehicles are plenty in the U-Pull-its for some reason: WHY ARE LSs so plenty? I sure loath a generic Check-Engine lamp. Gonna need a Decoder tool someday. Oh Auto-Zone does it free ☃️

[avman]

Yeah, the LS in my H2, as I stated in a previous post, was running around 4,400 at 70 mph on that trip to and from Lake Mead, pulling the "ultralight" 22 ft trailer and the bass boat behind that.
It was August...in the DESERT! It cracked the pressurized antifreeze reservoir on the way out of Lake Mead, and we had to have the H2+trailer+boat combo towed in. We wound up in Kingman, AZ at a GM dealership, so my wife and I went to the Mother Road Harley-Davidson dealership to get the first oil and filter change and service done on the V-Rod we had bought in Las Vegas, NV. ROUTE 66 on the V-Rod was a blast!

[3fastgtos]

Originally Posted by i82much

I say instead of talking about transplanting LS engines from trucks into Pontiacs, we talk about transplanting Pontiacs into trucks!

Doing it now. Putting a 614 headed 428 into my ‘69 C10. With a tunnel ram, hydraulic roller and a T56.

[Sirrotica]

Originally Posted by PAUL K

A 455 would make a heck of a tow engine! TH400 and a 3:08 gear with no need for over drive... We would need to start a thread to determine the best compression ratio and whether a 041 w/ Rhoades lifters should be used or an OF cam.

1973 Jeep J4000 (3/4 ton) 1972 455 from a GP, 068 cam, reworked 3 tube headers headers to clear the front driveshaft on right side, reworked OJet, T 400 transmission, shift kit, 4.10 axles. Towed, pulled, plowed until 1999 with it when the rear frame rail succumbed to rust near the shackle mount.

I sometimes wished I hadn't scrapped it, but at the time I was divorcing, so didn't have the means, to keep it, nor a place to fix it.

[PAUL K]

Originally Posted by Sirrotica

1973 Jeep J4000 (3/4 ton) 1972 455 from a GP, 068 cam, reworked 3 tube headers headers to clear the front driveshaft on right side, reworked OJet, T 400 transmission, shift kit, 4.10 axles. Towed, pulled, plowed until 1999 with it when the rear frame rail succumbed to rust near the shackle mount.

I sometimes wished I hadn't scrapped it, but at the time I was divorcing, so didn't have the means, to keep it, nor a place to fix it.

Bad Azz! Job well done

[slowbird]

Originally Posted by PAUL K

Sounds to me like you have a truck to roll down the hill behind your shop.

The OP got his answer in post #35

I definitely could careless how derailed any thread gets, but I do find it amusing how many issues there are with tow vehicles in the street section.

I also find it annoying how our GM vehicles hunt for a gear when towing up and down a grade. My brother solved his by wiring a switch into the system to keep that from happening. I solved the issue by putting the shifter in "D" when towing in an area with a lot of hills...FWIW

We solved it by tow with a 69GP with a 389 and tri-power that ran mid 12's. Towed like a champ and never lacked power or hunted for a gear

[PAUL K]

Originally Posted by slowbird

We solved it by tow with a 69GP with a 389 and tri-power that ran mid 12's. Towed like a champ and never lacked power or hunted for a gear

Is that the same GP that runs elevens? Did you guys tow with the 068 then install the 274 XE cam to race?

[slowbird]

Originally Posted by PAUL K

Is that the same GP that runs elevens? Did you guys tow with the 068 then install the 274 XE cam to race?

Yes runs 11s now. It's the other way around xe274 for towing, 068 for racing

[i82much]

Originally Posted by 3fastgtos

Doing it now. Putting a 614 headed 428 into my ‘69 C10. With a tunnel ram, hydraulic roller and a T56.

That's pretty cool. I have a 72 K10 that I plow with and I'd like to restore, and I've given some thought to a mild Pontiac 400 for the truck. But I already have a 396 with all the brackets and everything and I can't see starting from scratch on another Pontiac.

There is a lot of $ involved in doing an engine swap from scratch when you don't have any parts at all. Things like alternator and PS brackets, pulleys, timing cover, oil pan, oil filter adapter, stuff that you'd reuse if you had to rebuild your engine but you have to pay out of pocket for the first time you do a build.

[i82much]

Originally Posted by PAUL K

A 455 would make a heck of a tow engine! TH400 and a 3:08 gear with no need for over drive... We would need to start a thread to determine the best compression ratio and whether a 041 w/ Rhoades lifters should be used or an OF cam.

290B and an 850 double pumper on a Victor with E-heads, 4.56 gears and a loose converter. Everyone knows that's how you tow! How long you think those rear mud tires will last????

[PAUL K]

Originally Posted by i82much

290B and an 850 double pumper on a Victor with E-heads, 4.56 gears and a loose converter. Everyone knows that's how you tow! How long you think those rear mud tires will last????

No no no....you got it all wrong! OF cam hy'brid set-up, advanced four degrees, iron intake manifold with RPM plenum, Q-jet, TSP wiz bang tight converter with a Continental stator and 3:08 gears.... With an overdrive tranny..... The 290B would have too much stinky smell.

[Steve C.]

The ultimate guide to getting smells out of your hair


https://www.thelist.com/19468/ultima...g-smells-hair/


.

[avman]

Lol

[i82much]

Originally Posted by PAUL K

No no no....you got it all wrong! OF cam hy'brid set-up, advanced four degrees, iron intake manifold with RPM plenum, Q-jet, TSP wiz bang tight converter with a Continental stator and 3:08 gears.... With an overdrive tranny..... The 290B would have too much stinky smell.

The secret to running a big cam is to date a girl that smells worse than your car!