[Johnny406]

You can pick up very good used ported d-port heads for a grand or less here pretty often. Match the heads with a appropriate cam and intake to your fresh motor and you'll be there.

[ta man]

Originally Posted by gtome

I would say look at the stats. An LS engine can go 100k miles plus before you would even need to touch it beside an oil change. If you think you will get that out of an average stock bottom end fairly high hp 455.....your dreaming. Plus what is the redline of an LS and FI....cold starts.....not overheating.....MPG.......trans options...etc...etc...

Would surely cost more initially though.

Sure "some" have had good life and luck with the 455.........but compare that to those who dont.

Just I wouldnt rule it out by any means.

And if you decide to get serious about it I have a friend with an engine/trans/harness from an 02 TA ( IIRC) that he may be willing to part with. Wouldnt be an LS3, but a solid 350/365 and I rode in it just before it was pulled out.

How much power do you want?I agree with others a set of good heads and a good cam and you are at the 500hp level easily.What you really want is the question a Pontiac powered car or a Chevy powered car?It is up to you?Alot of us myself included are pure Pontiac engine guys we may all have different cars but it is the engine that bonds us together.

[MrPushrod]

I believe a 455 can go as long as an ls. But, good mileage and less maintenance is the deciding factor for a road car. Ls all the way with a six speed. Fill it up with gas and drive it. Trust me dude.

[HWYSTR455]

You spend the money on any engine, and you will get the same results as an LS. Care in parts selection, extra mile on machine work (crank indexing, balancing, lightening, friction coatings, etc), do EFi, DiS, and everythng behind it, you will get the same results. And who says there's no maintenance on an LS? Still some, just like every car.

I had a 400 with points dizzy, factory rebuild, TRWs, and basically only did oil changes and tune ups (cap, rotor, wire, points, plugs, carb spray-out). That thing was beaten, hard, and got close to 160k out of it. EFi and DiS would have made everything but the oil changes go away.

Coils go bad, sensors go bad, more probability for electrical problems, injector clogging or failing, nah, you're kidding yourself it you think it's a free ride. Go ask a repair shop what kinds of repairs they do on a regular basis, you'll get the idea.


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[MrPushrod]

GM has made a great engine, the LS. Reliable and able to make power. The new z06 with LS7 gets 26 mpg and 500 hp. Wow.

[HWYSTR455]

No doubt the LS series engines are good, but they are limited to meeting production costs and EPA regulations. I get 22MPG with a 461ci, and that's with a carb. All I'm trying to say is it can be done, and the LS engines are not the end-all be-all. Shoot, the new Ford modulars are better than the LS engines, going to put one of those in your Pontiac?


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[gtome]

Dang! I gotta hang out with you!! My 461 gets 8mpg!

I agree.....it can be done with a conventional Poncho. But dollar for dollar, you cant really count the LS out. And there are 100 cases to your 1 of guys that only got 17,000 miles out of theirs.

Dont get me wrong, I dont have an LS, and probly never will, but I would have to think long and hard about it if I had to start from scratch again.

[MrPushrod]

This month I saw a 69 chevelle with a turbo LS motor that runs low 9's, It was badass. I'm impressed with the ls. He wasn't limited.

[HWYSTR455]

Originally Posted by gtome

Dang! I gotta hang out with you!! My 461 gets 8mpg!

I agree.....it can be done with a conventional Poncho. But dollar for dollar, you cant really count the LS out. And there are 100 cases to your 1 of guys that only got 17,000 miles out of theirs.

Dont get me wrong, I dont have an LS, and probly never will, but I would have to think long and hard about it if I had to start from scratch again.

I've checked the mpg several times, even with friends that didn't believe me, still in the 21-22 range in the blazing summer heat. Might do better when it's cold out. Overdrive is a beautiful thing.

17k miles? Bummer! What happened to those? Other than not being built right. I've done 17k miles this year alone almost! Every engine I've built over the last 25+ years have all gone over 100k miles.

I'm not knocking the LS engines, and they do make great swap engines. They are fairly new technology, and are a proven success. My point is that it can be done with a Pontiac engine, and (obviously) arguably so. Sorry if I came across cranky!

.

[Nicks67GTO]

Lets be honest here. I like a traditional pontiac and i understand the purist thinking but the LS is LIGHTYEARS ahead of any engine Pontiac ever made. They are awesome engines. Point blank. Big power, awesome economy, little maintenance. If I was in your shoes and was going to do a pro touring type Firebird like yours, i would do an LS in a heartbeat. I chose not to LS my 67' GTO because i didnt want to cut it up. Its an original California HO car and is in awesome shape. Too nice to start hacking floors and stuff.

NOW in about 4-5 years when i tear into my 70' Chevelle Malibu you can be sure theres going to be an LS something in there. In fact im not going to rule out the possibility of LSing my 67' but its a slim chance at this point with the parts ive bought.

Just think of the possibilities. Those stock bottom end LS engines can be bought cheap. Throw a cam and heads on there, convert it to a carb and bam youre well over 500 hp with a mild idle and perfect reliability. Ive been running costs through my head about how much a damn 455 with KRE heads, forged bottom end is going to run me and i dont think 5K isnt to get me anywhere.

[Nicks67GTO]

BTW theres a set of 1st gen Camaro LS headers for sale over on PT.com right now

If youre going to go LS1, head over there. Theres a lot of knowledge and good guys and about 50% of them have 1st gen Camaros and Firebirds. Theres also a lot of high end, nice parts at a good price over there many times.

[gtome]

I really considered an LS before my last rebuild. The main thing for me was knowledge.........I had no clue how to do the wireing. Now with so much info out there, I think it would be much easier. Maybe the next go round.

[71 Goatman]

HWYSTR455,

What is your basic combo and gearing to achieve 20+ mpg with your 461? Auto overdrive or stick?
Just wondering, because I have a 462 with #96 heads, a mild cam (speed-pro 1175 224/234 @ .050), 9.5:1, ram air manifold, 2.5" exhaust with X-pipe, stock intake, Cliff Q-Jet, 3.23 gears with a 200r4, Continental 10" tight convertor non-lock up. I have managed a solid 16 mpg with steady state driving, 2200 rpm. If there is something simple I could change to improve slightly I would like to know.

Thanks

[MrPushrod]

Also, I tuned my 455 with a carb on a laptop with O2 sensors. My sh!t is dialed and I don't get very good mileage.

[Valley Pan]

If you ls lovers wait a couple of years, you can put a chebby volt electric motor in your cars. Smooth, quiet, maintenance free! Or maybe you would rather have a hydrogen fuel cell in your 67 GTO?

[gtome]

Id love to have the torque of an electric motor!

[guccieng]

i drive an ls3 6-speed 110 miles (week)daily, and prefer the poncho in the 'bird. it was expensive going with the aluminum heads, ram air manifolds, new intake, new carb, 11 bolt conversion, etc. worth every penny, though! the poncho is just more fun, imho.

[gtome]

I agree......... something about the raw power. That cant be matched...... the sound....the feel.

[1971WARBIRD]

for mileage and handleing i have my 89 GTA,but my old cars will have old school Pontiacs in them.i'm going with new tech as far as cams and heads and cranks,but sticking with the old school look.
71 GTO will have a stroked and ported 71 400 with a roller cam set-up.should look all stock,but put out over 500 reliable hp.

[goatman65]

Originally Posted by gtome

I agree......... something about the raw power. That cant be matched...... the sound....the feel.

Yep.Why have a Pontiac if you're gonna have the heart of a corporate [chev] engine? Save the trouble of the swap and just by a LS equipped 'Bird.