305E v6 performance?

[TJ's Chevy]

So....If any of you know me wel. () You'll know that I'm the type that likes to take the stock engine and punch it out for power. Like my 292 I'm sure some of ya'all have seen...if not, check out my build thread..But anyway...to the point. Just bought a 64 GMC and it has the 305E v6. Heard of some upgrades that can be done..500 2 barrel holley, hei, bigger dual exhaust...but that ain't close enough for me. No, I'm thinking compression pistons...Arias will make a custom set...little more lift on the cam, and if a set of 401 magnum heads will bolt on, then a set of those with the intake machined to fit a 4 barrel. I've been told the 351 heads will bolt on so, I'm thinking a set of 351 magnum heads for the larger ports and I think bigger valves..if not..well..changing that to. lol So anyhow...has anyone done this? Yes I know about the GMC guy and that forum so I don't need those links..I've looked there and only saw some stuff about the intake being machined for a 4 barrel, and Of Course cause I'm not a member I couldn't see the pictures. But anyhow...I guess my main question is..has anyone done a head swap? Or done the 4 barrel? Also saw a guy doing a turbo on his. Staying close to that one. lol So if any of you have done the 2 barrel swap I'm am interested as well.

[cableguy0]

Your biggest issue is that the rotating assembly weighs a ton in those engines. Rpm makes horsepower and you just cant spin those engines. I guess if you have a bottomless pit of a bank account you could have a crank,rods and pistons made but it will accomplish nothing other than to claim you did something different. It seems people get so caught up in the quest to be different that they lose track of being sensible especially when it comes to money spent vs gains made. The 305 and 351 v6 was never intended to be anything but a work horse running at near constant rpm.

[TJ's Chevy]

Originally Posted by cableguy0

Your biggest issue is that the rotating assembly weighs a ton in those engines. Rpm makes horsepower and you just cant spin those engines. I guess if you have a bottomless pit of a bank account you could have a crank,rods and pistons made but it will accomplish nothing other than to claim you did something different. It seems people get so caught up in the quest to be different that they lose track of being sensible especially when it comes to money spent vs gains made. The 305 and 351 v6 was never intended to be anything but a work horse running at near constant rpm.

I ain't building this engine for RPM I'm thinking of building it for more horse power and torque. The pistons would be for a compression increase. The heads for more air flow, and yes more lift means more duration, but more lift can be accomplished without much duration change. Being different is not a bad thing...everyone and their brother, cousin, grandfather, grandmother, and even sister in law has a 350 sbc in their trucks and cars that its almost insane. I hotrodded a 292 for power..it'll do 5000 if I want it to with no worries and oh yeah...it'll easily take on a 350. Cost more but hey, I'm gonna be proud knowing I don't have what EVERYONE else has, and when I pop the hood open to show someone I'll have their interest instead of "Oh its just another stinking sbc." So, I understand alot of people have budget builds and a 350 is an economical build but thank the good Lord there's a few of us out there with something different. I'm quite happy with my 305 the way it is, runs good, starts right up and will burn the tires or pull a stump with ease if I want it to, but I'm an adventurous type. And if people don't like that then they should quit trying to make other people live a boring life.

[duallyjams]

All I have done to my 305 is the 500 holley dual exhaust and electronic ignition, just those three made a big difference.
I have read threads where one was converted to a TBI, one added a turbo, one used connecting rods out of a 426 hemi with custom pistons and the rumor was it screamed.
Yes magnum heads will bolt on, the magnum intake can be machine for a 4 barrel.
A lot of threads on 401 and 478 being built and used for pick up.

I have a 401M stashed in the corner of maybe one day I'll get to it.

[TJ's Chevy]

Originally Posted by duallyjams

All I have done to my 305 is the 500 holley dual exhaust and electronic ignition, just those three made a big difference.
I have read threads where one was converted to a TBI, one added a turbo, one used connecting rods out of a 426 hemi with custom pistons and the rumor was it screamed.
Yes magnum heads will bolt on, the magnum intake can be machine for a 4 barrel.
A lot of threads on 401 and 478 being built and used for pick up.

I have a 401M stashed in the corner of maybe one day I'll get to it.

Yeah I've heard alot of good things about the 2 barrel swap, hei, and bigger dual exhaust. On the GMC club forum a guy is in the process of adding a turbo. Arias will make a custom set of pistons. Cool on the magnum head bolting on....new they probably would, just wasn't entirely sure. lol Yeah there's a guy on youtube who has a 401 and 478 in his 69 chevys. They move thats for dang sure.

[71K20chevy]

Originally Posted by TJ's Chevy

I ain't building this engine for RPM I'm thinking of building it for more horse power and torque.

That's the problem...you can't make HP without RPM. HP is simply a by product of the torque produced at a certain rpm. However peak torque is not directly related to RPM so you shouldn't have much problem getting more tq.

[TJ's Chevy]

Originally Posted by 71K20chevy

That's the problem...you can't make HP without RPM. HP is simply a by product of the torque produced at a certain rpm. However peak torque is not directly related to RPM so you shouldn't have much problem getting more tq.

I hear ya, though more hp can be accomplished by increased compression, larger bore, more air flow, induction, all those still are major increases in torque more than anything.

[duallyjams]

GMC V6 is just plain cool and it will run all day long. I love mine and would not swap it out.

[TJ's Chevy]

I agree...love mine to. Its another buzzin half dozen. lol

[MusicMan70]

I copied and pasted this from somewhere; maybe this forum or another, I'm not sure. It does have some specifics about performance changes.



Heres a little about these motors I learedt back in the mid 80's. My grand
father gave me his 1965 GMC 1t 4x4 that came with the gas 351c v6. I rembered
from a kid that this old truck would out pull anthing and never broke down. The
old 351 was getting tired with about 200k on it so i decided to rebuild it and
of coarse hop it up. So I started looking into performance imfo on these motors.
That put me in contact with Babe Erson. He told me about the gas 478M motor and
how with some work the big 478m v6 will easily make more tork and hp than a
mildly built 454bbc. So I bougth a 478m motor from the junk yard and went to
work per Babe's rec's. The first thing was to throw away the stock 4 ring
pistons and masive rods that weight about the same as a complete hemi motor. I
had a crank grinder turn the rod journals down to a much smaller size to fit a
426 hemi rod. I had BRC make some new lighter 3 ring pistons that also raised
the cr up from 6.5 to 9.0. Engine dynamitics lightened the crankshaft alot and
rebalanced every thing for me. Babe made me a special cam and all the vale train
parts. I ported the heads and polished the combustion chambers myself. I also
made a sheetmetal cross ram intake with 1 850cfm Q Jet carb and a set of home
made 1 3/4" headers. Once I got all the tuning done on this motor it was one
tork animal that would rev easily to 5.5k. It broke the transfer case right away
so I put in a beffier transfer case out of a newer ford truck I think then I
blow the old gmc rear end so I upgraded it to a dana 70 with posi. I also
upgraded the old truck 4 speed to a newer 5 speed that could be shifted much
faster. I had put big 38" tires on this truck and could smoke them in 2nd gear.
It did not do to bad on fuel also at about 12 mpg fully loaded with a 10ft
camper and pulling a 30ft enclosed trailer running about 65mph. I wish I know
where this truck (James) is today as I would try to get him back

[TJ's Chevy]

Thanks for the reply Music Man! Yeah, I'm liking what that guy did. Man that's sweet.

[MikeB]

I think different is cool if you can afford it.

I thought about rebuilding my truck's 250 six and scrapping the integral head & intake manifold, or maybe going to a 292. But after looking into parts prices, it would have cost more than rebuilding a junkyard 350. And the 350 would make 25%-50% more torque and horsepower. Of course, now the 350 project is costing a lot more than it should have!

If I could turn the clock back 6 months, I would at least tear down the 250 to determine if the short block was rebuildable. But had I gone that route, the 2.73 axle would have to go. Paired with the 250 six, it's like asking grandma to move a refrigerator.

[TJ's Chevy]

Originally Posted by MikeB

I think different is cool if you can afford it.

I thought about rebuilding my truck's 250 six and scrapping the integral head & intake manifold, or maybe going to a 292. But after looking into parts prices, it would have cost more than rebuilding a junkyard 350. And the 350 would make 25%-50% more torque and horsepower. Of course, now the 350 project is costing a lot more than it should have!

If I could turn the clock back 6 months, I would at least tear down the 250 to determine if the short block was rebuildable. But had I gone that route, the 2.73 axle would have to go. Paired with the 250 six, it's like asking grandma to move a refrigerator.

Yeah...it took me 2 years to save up for my 292. But I'm the type that does what I want to do no matter how long it takes. I wanted something cool and different and I got it. And now I am happy instead of....wished I did this...wished I woulda done that like some many people here. When people see my 66 they are always stoked about the 292 instead of "Oh nice...just another stinkin 350....lets go." And I'm happy knowing I did what I wanted to do.

[clinebarger]

Originally Posted by TJ's Chevy

Yeah...it took me 2 years to save up for my 292. But I'm the type that does what I want to do no matter how long it takes. I wanted something cool and different and I got it. And now I am happy instead of....wished I did this...wished I woulda done that like some many people here. When people see my 66 they are always stoked about the 292 instead of "Oh nice...just another stinkin 350....lets go." And I'm happy knowing I did what I wanted to do.

That's cool you wanting to different & all, But you don't need to rag on SBC's. If you put that money in a 350 it would make more horsepower & torque because your dollars go further.

[TJ's Chevy]

Originally Posted by clinebarger

That's cool you wanting to different & all, But you don't need to rag on SBC's. If you put that money in a 350 it would make more horsepower & torque because your dollars go further.

Well imop a project isn't just about "best bang for the buck" its about what you want to do and how you want it. I'm not against SBC's...believe me I was going to do a swap before I found out of all the options available for the I6. What I rag about is people telling other people that building an inline 6 is a waist of money. THAT's what gets me upset (1) because its not true. (2) cause there are alot of people who go the 350 route because of it. And its a darn shame when I go to car shows and see nothing but SBC's in almost 80% of the chevy cars and trucks....The other 15% being BBC's(nice change) and the 5% being stock or hopped up inlines(keeps my eyes looking at that car or truck the longest). But everyone has and is entitled to their opinion and I'm stating mine is all. If I was one of those people who asked this forum about building the 292 I probably would have a 350 in there today and be staring at my 292 saying to myself.."Man, would have been nice to see that thing hopped up." But I decided to learn for myself instead of asking other people's opinions and I'm a happy man today because of it. And not to say asking someone's opinion is a bad thing. I've been help a TON and a half by this forum. But finding things out for yerself ain't a bad thing either.

[MikeB]

Originally Posted by TJ's Chevy

When people see my 66 they are always stoked about the 292 instead of "Oh nice...just another stinkin 350....lets go." And I'm happy knowing I did what I wanted to do.

So I pretty much suck, huh?

Seriously, I do know what you mean about being told anything smaller than a 350 is a waste of money. Can't tell you how many times I ran into that attitude when building a 327 for my 55 Chevy sedan. And guys building a 265 or 283 really get beat up.

Several years ago, I gave away a perfectly good 307. It would have made a great budget engine for my truck, and would have been different, at least internally.

[TJ's Chevy]

Originally Posted by MikeB

So I pretty much suck, huh?

Seriously, I do know what you mean about being told anything smaller than a 350 is a waste of money. Can't tell you how many times I ran into that attitude when building a 327 for my 55 Chevy sedan. And guys building a 265 or 283 really get beat up.

Several years ago, I gave away a perfectly good 307. It would have made a great budget engine for my truck, and would have been different, at least internally.

Yeah, I hear ya. But like I said...I understand the "best bang for the buck" deal, but I'm just a nut so. haha

[mechanicalman]

Love the "one off" projects that "dare to be different". Stick to your guns, enjoy yourself, and remember this one important thing:

It's YOUR truck and YOUR happiness. The best, most important thing you can get in life is happiness, and it comes in all ideals, shapes, sizes and colors.

[TJ's Chevy]

Originally Posted by mechanicalman

Love the "one off" projects that "dare to be different". Stick to your guns, enjoy yourself, and remember this one important thing:

It's YOUR truck and YOUR happiness. The best, most important thing you can get in life is happiness, and it comes in all ideals, shapes, sizes and colors.

I couldn't agree more! lol

[MikeB]

Originally Posted by mechanicalman

It's YOUR truck and YOUR happiness. The best, most important thing you can get in life is happiness, and it comes in all ideals, shapes, sizes and colors.

And it's not like a big V-6 engine will be a wimp, like a smaller inline six. (OK, a 292 can be pretty strong, too!)

[TJ's Chevy]

Originally Posted by MikeB

And it's not like a big V-6 engine will be a wimp, like a smaller inline six. (OK, a 292 can be pretty strong, too!)

Know a guy with a hopped up 250...he leaves 350's in the dust all that time. lol No his isn't turbo charged! Ya gotta admit though....the 350/260 is perrty wimpy. Driven a few and they are as slow as my stock 292...LITERALLY. The 350/290 isn't so bad but is a gas guzzler for the power it makes.

[mechanicalman]

Originally Posted by TJ's Chevy

I agree...love mine to. Its another buzzin half dozen. lol

I only own small blocks: 350, 355, 400 with automatics: T350, T400 and a 700R4.

So basically I'm jealous LOL. I love a "one off" project, and my dream truck would be a 351 V6 TOTT 4WD short-bed step-side.

Kinda like to have a big block in the herd, I suppose the SB400 will have to suffice for now.

If I had a V6, I would be an old dog trying to learn new tricks, oops, I mean trucks.

[Ironangel]

Those valve covers gotta be good for 100 extra horsepower!

[mechanicalman]

Originally Posted by Ironangel

Those valve covers gotta be good for 100 extra horsepower!

VISUAL HORSEPOWER is REAL I can SEE it!

[TJ's Chevy]

Actually the story goes that the plaid valve covers were the same treatment at painting an engine ford blue.