[Formulajones]

Originally Posted by "QUICK-SILVER"

I for one hope this is a joke. I was ready for the 350+HP, torque monster from hell engine build. That was "REAL LIFE" pump gas friendly and would pull off 15 mpg or better while totin' a load. An engine that didn't need 5 or 6 gears to get moving and run down the road. And wouldn't have to down shift three times when you hit a hill.

You'll need a bigger engine than a 350 to pull that off. And yes I'm sure he's joking, hence why I was joking with my comment.

["QUICK-SILVER"]

Originally Posted by p4msi1

Next, I have 4 - 455's, 2 - 400's, 1 - 301, 3 - 350's. and maybe another 428 and 455 on the way.

Originally Posted by Formulajones

You'll need a bigger engine than a 350 to pull that off. And yes I'm sure he's joking, hence why I was joking with my comment.

Appears he has that part covered.

Clay

[Formulajones]

Yeah I saw that, I'm referring to his original question.

[hurryinhoosier62]

Originally Posted by Formulajones

Yep, that will make a very nice tow engine with a broad power band, and they have excellent cylinder heads. I fooled with the larger bore 6.0's for quite a while. A 4" crank 402/408 combo makes fantastic power for it's size.

I’ve found a few 6.0s that the owners didn’t want an arm and a leg for, but I’m leaning toward a 5.3 block bore to LS1 specs (3.905” bore) with the 4” stroke crank/6.125” Molnar rods. Ported 317 heads milled to 71cc chambers will top it off.

[92GA]

Originally Posted by p4msi1

OK, the heads are 73 #46 with press in studs and 1.96/1.66 valves.

Next, I have 4 - 455's, 2 - 400's, 1 - 301, 3 - 350's. and maybe another 428 and 455 on the way. I am not looking for all these engines, they just "show up".

So I restored 1- 84 chevy truck and just ran the reman. 305 that was in it till it started to knock, I did not want to put a Pontiac in it at first because of all the accessories and mounting brackets...SOoooo..I bought a Blueprint 383 crate motor that for the truck. It had ample power but the cam loped too much and vacuum was too low for the power brakes and shook the truck at idle with the a/c running. No more big cams for an everyday driver!!!! Last year I was towing my Firebird home from racing and it started to slowly lose power, I figured I may not have tightened the distributor holddown screw and the timing was backing off. Made it home and the next morning fired it up and it sounded like hammers in the block. I'm figuring a broke wrist pin maybe a bearing but oil pressure is still good and no debree in the oil. No more Chevy engines in my vehicles.
I have since restored a 1984 GMC 2500 LWB truck also and it will get a pontiac motor too, after the 305 expires.
Gas mileage is a consideration as the factory tanks are about 16 gallons.

Steve

If you truly have all those Pontiac engines, why in the world would you choose a 350? The 383 is normally a great engine provided it was built right. Min would be a 400 and prefer a 455 if you're really going Pontiac. I'm a GM guy, NOT a Chevy hater at all. Have built and raced them both, but I'd NEVER use a Pontiac 350 in nothing. That 383 will have a LOT more guts than a 350 Pontiac, I've had them both.

[PunchT37]

Well, that`s it. All Pontiac engines except 400`s, 428`s and 455`s to the smelter. Maybe 389`s or 421`s if you can find pistons. Long thread just to get to this point.

[p4msi1]

Originally Posted by PunchT37

Well, that`s it. All Pontiac engines except 400`s, 428`s and 455`s to the smelter. Maybe 389`s or 421`s if you can find pistons. Long thread just to get to this point.

I will guaranty that this P350 I will build will out perform the Blueprint 383 that is in there right now.
Amazing...........I asked about a cam choice and it ends up everybody wants me to go to BBC Chevy, LS Power, or a used chevy diesel truck. I think this a perfect use of a P350 for everyday use and occasional towing.

[PunchT37]

Originally Posted by p4msi1

I will guaranty that this P350 I will build will out perform the Blueprint 383 that is in there right now.
Amazing...........I asked about a cam choice and it ends up everybody wants me to go to BBC Chevy, LS Power, or a used chevy diesel truck. I think this a perfect use of a P350 for everyday use and occasional towing.

I hear ya. Not everyone is pulling a full horse trailer up pikes peak.

The 350 could still handle the heat better than the 455. Even though it would make less power.

[Formulabruce]

IMHO, if you use the 46 heads, PIN the studs , The 670 are all set.
stock 350 2bbl in 71 was 350 TQ. with good cam selection and some work you might get that with the 46's
350 Torque is nothing to sneeze at..
Good luck!

[HO Kenny]

I had a 68 350 HO in a firebird convertible with a comp cams high energy 268 in it. It worked much better than the original cam. I had shaved the heads and shaved decked the block so it had a bit too high compression for the cam. I shifted at 5300. Any lower would spin the tires too much and any higher was totally unnecessary! But it did pull to 6000 it top gear. With 3:23 gears and a 2.20 first gear it was hard to launch. With a better first it would have been great. Good Torque throughout the entire rpms. The p350 can put out a lot power and torque for its size. More than your average sbc without reving to the moon.
I often thought it would make a great truck engine and wanted to put one in one myself. I new a tow truck driver that go tired or replacing his sbc so he put in a Pontiac. He was very happy with it.
Go for it and let us know how it goes.
Ps the heads had a lot of sharp edges in the valve bowl at the transition between the casting and machining. I don't know if that's common in smaller valve heads, but it worked well cleaning that up.

["QUICK-SILVER"]

First post titled; P350 for towing

Originally Posted by p4msi1

I want this motor to be smooth, quiet and super torque output for towing.

Then a near 180

Originally Posted by p4msi1

I think this a perfect use of a P350 for everyday use and occasional towing.

Bootleg Turn by accident don't count. That's just plain losing control.
Doing a bootleggers turnaround on purpose requires some skill. Knowing your vehicle well and how it acts with different road conditions.

Definition: Bootleg turn. A bootleg turn is a driving maneuver intended to reverse the direction of travel of a forward-moving automobile by 180 degrees in a minimum amount of time while staying within the width of a two-lane road.

I see a big difference between a purpose built "tow truck" and a daily driver with "occasional" towing.

For a 'real' tow truck, I'd want it to not labor while totin' a load. 455 could do that easy.
For a daily driver, the P350 could be made to shine. It just wont run as free as the 455 while occasionaly towing.

Failure leaving out the real purpose of the project has led to a bunch of unecessary post...Like this one

Clay

[Will]

I don't see how those two statements are exclusive or contradictory to each other at all....????

A smooth, quiet engine with super torque output would be a great daily driver engine as well as towing engine.

Any controversy in this thread comes from the typical "cubic inches are king" mindset. Which, in reality, can't be argued but shouldn't really be a factor. The question was not whether a 350 or some larger engine should be run but how best to set up a 350 for the desired goals. Whether the 350 is the best possible choice isn't the issue.

I'd think a 350 should work good if you can overcome the compression ratio and valve size issues. How much lift can you run with big valve heads before valve-block interference becomes a problem? If you can get up to .450" or greater lift then it's a non-issue and I'd run the 670s on it. If you're limited to less than .450" then I'd try to find a set of small valve heads that will give a good CR and do some port work on them.

I'd also try to maximize torque in the lower-mid RPMs, say from 2500-5000 RPM. I bet with the right cam, exhaust, and head choice you could get 400 ft-lbs. Work it like a diesel engine - shoot for a narrow powerband that makes as much torque as possible then gear the vehicle to take advantage of that. A little lope at idle would be okay as long as it's pulling enough vacuum.

I bet that Comp HE260 would be a good choice.

[Sirrotica]

http://www.hotrod.com/articles/hppp-...-engine-build/

Putting a 4 inch stroke crank into a 350 block to make 383 cubic inches, and 460 HP. It isn't the optimum for a race engine, but for a tow vehicle I'm sure it would pull about anything you'd need to pull on an open trailer.

By the time you invest in the 4 inch rotating assembly you might as well build a 421/428 though.

Although I have used a stock bore stroke 350 in my jeep wrecker, if I had a choice like the OP does, I would probably opt for a 389/400 just because the other blocks have the exact same stroke, but a larger bore. In my JEEPS I've had a 350,389,400 and a 455. The 350 did okay but the 389 and the 400 were better towing engines. The 455 was overkill because of all the torque I was breaking transfer cases etc, that just weren't designed for that much torque. I also trashed a stock T400 with the 455. If I hadn't of been so lead footed, the driveline would have lasted longer. The 455 never even knew there was a car hanging on the wrecker sling no matter how heavy it was.

[maxumtorq]

I think it depends also on how much he has to spend on this project. Not everyone has 3 or 4 grand laying around to rebuild a Pontiac, I say drop it in and hammer down. You can always pull it back out. Nobody is talking me out of putting p350 in my truck in October. Financialy I cant afford nothing else and have all the parts I need for the p350. But I don't pull anything bigger than a ten ft trailer I use for firewood. I would do what you can afford brother. Just my 2$ worth. I would love to race you in it now but we would probably fall asleep before the finish line.

[p4msi1]

QuickSilver = Low comprehension level. It is a truck capable of towing, how often or how many times is irrelevant. I want to use these 350's because I have them and want to save the 400's and 455's for maybe the next generation of Pontiacers. I built 535's for my other 2 Firebirds. I guess some people need elementary explanation. I thought I was clear at the very start, I was asking about the Summit 2800 as suitable cam selection! Listen to me, I am building and installing a P350 for my 84 Chevy Truck (s) to replace the POS 383 and that is the end of that story.

Will / Formulabruce= High comprehension level. Offered constructive advise.

Steve

[Lee]

Originally Posted by hurryinhoosier62

You’re talking about the 549. The block alone weighs nearly as much as a complete Pontiac engine. Not overly powerful, either. IH never had one that was rated over 250hp. Parts are difficult to find on a good day.

No, IH used 348 and 392 inch V-8's, gasoline, in buses and dump trucks. Shaft rocker arms, forged cranks and rods. They used the EXACT same engines in Travelalls, Travelers and Scouts. The cams all had smaller exhaust duration than intake duration, and power curves were DONE by 4,000rpm, but they could pull massive loads off-idle with a manual transmission. HP ratings were crap, but they could pull - pull nearly anything.

[Formulas]

Like i said in a earlier post 2800 cam is a nice all around P350 camshaft torque and RPM range is what you would expect in a 60's base 4bbl engine

You could go with a smaller cam in search of more torque but almost every truck will spend some time in lower gears pulling and you will want some top end and a strong mid range

Im half way moved from CA. To WV where i dont have to dick around with smog and i have a tight 1977 chevy 3/4 ton long bed and if i end up taking the truck with me i will be dropping a Poncho in it

[PunchT37]

I'm startin to think that this cam with the 670's would still be torquey and get you closer to 320 hp.

http://www.lunatipower.com/Product.aspx?id=1774&gid=287

[72LuxuryLeMansLa.]

Originally Posted by PunchT37

I'm startin to think that this cam with the 670's would still be torquey and get you closer to 320 hp.

http://www.lunatipower.com/Product.aspx?id=1774&gid=287

I ran this combo through my engine analyzer. I set the scr at 9.5 because I don't know the chamber size. The cranking compression would be 205psi with that cam at 9.50scr.

[PunchT37]

Originally Posted by 72LuxuryLeMansLa.

I ran this combo through my engine analyzer. I set the scr at 9.5 because I don't know the chamber size. The cranking compression would be 205psi with that cam at 9.50scr.

Chambers are advertised at 72. Gotta figure ****ty head gaskets unless he goes Cometic.

Which I would. Need as good a quench and compression as possible, especially on the 350.