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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: Layne on November 05, 2009, 08:06:25 pm
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So we all know that the 305 is a decent motor for your everyday driver. But let's discuss the other ones - 301 302 and the 307. Are they worth their salt economically, best bang for the buck, or are they just another really good boat anchor?
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The 301 is a Pontiac motor, that one for the most part is junk. The GM 302 was one good running motor in a 69 Camaro. It was a combination of a 283 and 327 if my memory serves me. The 307 was a decent offering, had an old Chevelle with one in it, had no complaints.
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Actually the pontiac 301 is a very good motor and great on gas. Personal experience
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Actually the pontiac 301 is a very good motor and great on gas. Personal experience
I didn't mean to "dis" the 301, I just remember replacing a bunch of them in the early 80's because they blew up. I remember fitting a Pontiac 400 in place of the 301 in a 78 Grand Prix, boy that car flew...
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There's a 307 in my 74 blazer (being replaced with a 462 bb) It's a dog. I can honestly say it feels a little more peppy than a 305 though.
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I had a 79 GP with a 301. It leaked out of every thing imaginable- even the diff leaked. lol. That was when I was 15 and didn't know anything about cars. Had it for a week and it was one of those "back 40" cars, you know the ones that aren't road worthy, but sure were fun in the back yard :P
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i personally love all the small inch gm v-8's: The vsbc (very small block chevy), the ssbc (small, small block chevy---262, 265, 267 etc.), the smog-era motors and the like. i guess you had to be there; imagine an 84 grand prix with a 305. Man, those were great times.
1) 301. i think these pontiacs(also from personal experience, 265) were very dependable, smooth running engines.
2) Oldsmoboggie had their 260, and their own 307
3) Right now, i've got a 305 in the truck. Yes, there is an immediate feel of lesser power and torque as compared to the 350 crate that was in there previously, but it runs great and gets the job done.
a) Again, i'm wondering why no one has taken a stock 305 and simply bolted a 6-71 blower on top; i think this would put all doubts towards the 305's performance potential to rest. i plan to do this, if and when my planets align.
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Most people wouldn't put the kind of $ into supercharging a 305 when they can build a 350 for the same price with better end results.
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The 305 is a decent little engine. I had the privilege of driving a real X code 302 and that little beast kept me pretty planted, course the 4.10 gearset was a help. My ex-wifes father has a 58 impala that I think has a 265 in it, a cruiser.
In my humble opinion the big inch small blocks are where its at unless all you wanna do is cruise, low and slow. And these days I'm all about low and slow, but I like having the ability to embarrass some one at the end of my right foot.
D
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Most people wouldn't put the kind of $ into supercharging a 305 when they can build a 350 for the same price with better end results.
Agreed. But my point was, you can pretty much get 305's for next to nothing as they are practically falling out of trees and with the investment of a 6-71 (what, like 2 grand) you would have an amazing performer for only 2grand and also putting to rest the dubious performance reputation of 305's (which, in my opinion is undeserved).
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^ The problem with sinking 2k at least into a 6-71 on a 305 is putting all that strain of positive pressure inside a motor that was at best built to withstand maybe 180 HP. I could see bent and broken internal parts in short order.
My dad had a 81 Regal with a 267 2bbl and a 2.29 rear end :o Yeah it was pretty wimpy but oddly could beat my brother's friends mom's 84 Cutlass with a 305 4bbl in a race, but my dad's 2nd wife 78 Omega with a 305 4bbl felt consideraly gutsier than the Regal did.
My first vehicle I ever had was an 81 Jimmy 2wd Sierra Classic with a 305 2bbl, TH350 and I'm not sure what rear end but it had a Gov-lok. Nasty slow but could almost edge out a 83 C10 2wd longbox 305 4bbl with straight pipes lol Even with the top off, it wouldn't turn the tires on pavement.
2 305's I did like were the 180 HP HO that came in the 83-84 Z28's and TransAms with that motor as an option. Also came with a 5 speed and 3.73 gov-lok rear. The other was the 235 HP 5.0 TPI in the 91-92 Z28s. With a 5 speed, it was a mid-14 sec car I think.
The 307 as I understand it was a stroked 283 and the 327 was a bored-out 307. The 350 then was a stroked 327.
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Boosting a stock 305 will = engine failure
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Interesting debate. This has all been played out many times before, but I can't resist. I had a '79 monte carlo with a good running 305. Very happy with it. I also had an '87 camaro with a 305 and a e4me quadrajet with an overdrive transmission (700r4, I think). That thing would absolutely fly. I can only assume it was all stock. On the other hand I don't think I could ever be satisfied with one in these trucks. I'd rather have a 250 straight six. Supercharge one might be interesting but it wouldn't make much sense. Displacement is cheap.
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Right! I had a 250 in mine and loved it, but the 400 is much better for my taste! :D I've seen a lot of debate with the 305, but I was curious about the other mouse motors and wanted to know if they had the same boringness. Lol.
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^ The problem with sinking 2k at least into a 6-71 on a 305 is putting all that strain of positive pressure inside a motor that was at best built to withstand maybe 180 HP. I could see bent and broken internal parts in short order.
Boosting a stock 305 will = engine failure
Obviously, on a totally stock engine, namely a 305, you don't want to get to crazy with the boost; i'm thinking (will do more research) 14lbs in very occasional short spurts would be ok if we assume a stock compression ratio of 7.5 to 1. Up to 7lbs should be ok all the time.
i think high RPM is way more detrimental than pressure on the pistons/rods/crank etc.
Will clarify further later; Too tired now.
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I currently have a 250 inline six in my '80 2wd swb 4 speed truck. I had a 305 in my '82 lwb 4x4 4 speed truck with 31x10 tires and i got better power and mileage out of the 82. 17mpg with the 250 and 18 with the 305 in a bigger taller heavier truck. go figure. I am considering finding a camaro 305 and seeing what kind of mpg's i can get. I don't need to be really fast just don't want to be really slow either. but most of all i want to drive it without stopping at the gas station everyday. oh by the way both were mostly stock engines.
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Obviously, on a totally stock engine, namely a 305, you don't want to get to crazy with the boost; i'm thinking (will do more research) 14lbs in very occasional short spurts would be ok if we assume a stock compression ratio of 7.5 to 1. Up to 7lbs should be ok all the time.
i think high RPM is way more detrimental than pressure on the pistons/rods/crank etc.
Will clarify further later; Too tired now.
So once again why would you waste your $ supercharging a 305 when it would cost the same to supercharge a 350?
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No, i agree; IF you were going to take the engine apart and put in forged pistons/rods/crank etc. to make a serious supercharged/turbo'd engine the yes, it would most probably be easier/cheaper/better to start with a 350.
But i was talking about totally bone-stock; Just take the stock intake off, bolt the blower on and then put the quadrajet, or whatever carb you're going to use back on, and go! In this case, i think you could have a very surprising perfomer without too much work or money relatively speaking.
UPDATE: 6-71 blower actually cost closer to 3K. But think of the time savings---install blower vs. change cams/compression/heads etc.
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From what I've read here and there, other than less cubic inches, the main reason 305s aren't used much is lack of aftermarket heads available. 350s are used so much because practically all aftermarket parts are engineered for them.
That little 302 was a bad*** engine though, I'd take one no problem if I had an old camaro to play with.
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I wonder why the 302 vs the 305 is such a big difference? Heads? EPA? Different eras of motors in vehicles?
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Block-wise, I believe it was bore and stroke. 302 was an over-square motor, with large bore and short stroke = Hi RPM screamer. Couple that with large-valve heads, a cam to match and a good-flowing intake and you have a revver which worked well with 4.xx+ gears and a lighter car. 305s were always saddled with crappy heads, cam and intake plus they were small bore. Yeah, different eras to contend with.
Put a 302 in one of our trucks and you probably wouldn't be too happy with it.
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305 were built for economy. 302 was 1 cube under the max size for 5.0L engine for the race series, you can make a 305 have power, but if you were chosing a motor to build for power and weren't limited to size, naturaly you will chose the largest possible.
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Put a 302 in one of our trucks and you probably wouldn't be too happy with it.
Personally I would sell off the 302 for big $$ and then would have the money to buy just about any crate motor out there that GM makes.
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can a 305 be God motor sure..
cam swap would make a world of difference even a comp 257H cam woudl wake these things up
i degree a stock 305 cam once 168* intake 175* exhaust lift at vlv as .325/.375 I/E and a 105*lsa
manifold nice dual plane
exhuast
carb
headers
even heads would make a difference
and you know what all that is swapable to a big inch SBC
geting 250-275hp out of a 305 is not hard