zya5point0

iTrader: (4)

So since I'm "older", I still randomly browse the magazine racks. Anybody else notice a few months ago the magazine article (hotrod? Phr? I forget) comparing a built 305 to a built 302? I'm old enough to remember my Ford loving buddy's bragging about how Chevy needed to put a 350 in the Camaro to beat the little 302. I remember reading in a magazine back in the 80's that the reason a 305 was hard pressed to compete with a 302 because the small bore limited cylinder head design. How the heck is it that people with engineering degrees were so stupid as to kill the dz302 in 1970 and come up with the turd that became the 305?? Did Chevy have Ford guys working for them back then? Just something I've always wondered, and asking if anyone else has also always wondered?

Tibo

iTrader: (15)

Why in Gods name is a 305 SBC still mentioned (as anything but a historical footnote) in a 2017 performance car magazine?

zya5point0

iTrader: (4)

Because some magazine editor wanted to do a 5.0 vs 5.0 test, lol! I can see the logic for the comparison, but my main question still is, why Chevy, why?? This may have been "rocket science" in 1969, but if you got an engineering degree??

Fast355

iTrader: (2)

Easiest answer for this....The 302 was never known for low-end torque even at 11:1 compression. At 8.6:1 it would have been an even bigger dog than the 305 with the same torque converter, gearing and 4spd overdrive. The smaller bore of the 305 also gave cleaner emissions. The 305 made its torque peak in the 1,600-3,000 rpm range depending on the model and year. The longer stroke of the 305 gave more low end punch than the shorter stroke of the 302 and made for a car that felt strong. The Ford 302 never has felt strong in the lower rpm range and was a DOG with an AOD and taller gears. A coworker just built up a roller cam 302 with the good heads out of an exploder put the E303 cam, headers and a nice 4bbl on it and put it into a fullsize Bronco on 33s with 3.55 gears. At anything less than 3,500 rpm and WOT it is a DOG. The 268 flat tappet cammed Vortec 305 in my brothers 1999 4 door LT Tahoe will wipe the floor with it. Just to accelerate from 60-70 mph on the highway he has to step on the 302 hard and cause the AOD to drop atleast one gear. The 305 in the Tahoe accelerates in OD with 3.42s and 32" tall P305/50R20s. I drove the Tahoe not long ago to work one day to change the oil and a few other things and ended up in a short drag race with the Bronco. The Tahoe jumped the Bronco by about 2 lengths in 1st gear and kept pulling away up until I let off at 75 mph.

zya5point0

iTrader: (4)

^^^^I see where you're coming from. But it just behooves me that Ford kept their little 302 all these years later... Well till they did the 4.6 or whatever it was/is(I'm not a Ford guy obviously, lol). I understand the torque side of it, but, can it not be compensated for in cylinder head design? Or is that an engineering thing still going on today?

zya5point0

iTrader: (4)

And I know the whole emissions thing started back then, but how much difference could 3 cubic inches make??

Fast355

iTrader: (2)

It was not the cubes. It was the bore/stroke. Ever notice how Ford had to go port fuel injected in their models way before GM did. Ford trucks were PFi all the way back in 1986. GM did not even bring TBI out until 1987 on Trucks and 1988-1989 on most cars.

Just be thankful Chevy was the cheaper of the corporate motors to build. The F-cars could have had swirl port head 307 oldsmobiles in them making 140 hp or gasp a 120 HP 350 diesel.

zed-028

305 was always a bit of a dog mainly due to the smaller bore and the peanut camshaft. Replace the cam, throw a decent exhaust on it and it and it goes from "overweight 14 year old labrador" to "somewhat healthy but still a bit lazy sheepdog"

whinge about them all you want, they are disturbingly reliable but will never be any degree of a performance animal

AlkyIROC

The 302 wasn't really a mainstream production engine. It's main purpose was to allow the F-body to compete in the transam series which had a limited engine displacement. Of course in these road race cars, the short stroke could easily survive an 8000 rpm rev limit and that doesn't mean it's a good daily driver engine where you would rarely go over 3000 rpm.

With much more modern engine components just about anything can be made to make a lot of power at different power ranges. My 588 BBC has a huge bore and overstroke and can easily spin to 8000 based on the cam grind but I only shift it at 7400.

Comparing 5.0 to 5.0 is comparing apples to oranges. Two totally different designs that are not even close to the same in specifications however when built with very similar components (compression ratio, cam grind etc) both engines put out roughly the same amount of power. The chev SBC head bolt layout is much better than the Ford 302 with extra bolts providing better clamping force.

You could also compare a Chev 350 with a Ford 351 and get different results.

Chev, Ford and Dodge also made a 400 CID engine and all 3 perform differently. Technically Chev made a SBC and BBC 400 engine. The BBC version was a factory bored out 396 making it a 402 and the much larger BBC heads could feed that displacement better than a factory produced SBC head could.

Like so many other engine designs the biggest reason to drop a particular design and move to a new platform is reliability, better fuel economy and reduced emissions. Looking at engines like the LS platform, it far out performs any of the first gen SBC engines. Even a small basic 4.8L is a much better engine than the 302/327/350 engines ever were from the factory.

Fast355

iTrader: (2)

Yep newer designs are better that is for sure. My Luxury Sports Sedan has a 338 CID V8 that made about 440 hp at the crank STOCK despite a 420 hp factory rating. Intakes/Exhaust/ECM tune has it up another 50 hp at the wheels compared to stock.

Tootie Pang

iTrader: (2)

I was very involved in the 80s 5.0 vs 5.7 fun. I was squarely in the Ford camp. Had three 5.0s. Always wanted an IROC back then but this is my first.

Having crawled all around both cars now, I can say that they had different priorities. Chevy went for a superior all-around car but had to compete on price. The IROCs handle far better than the 5.0s and the gear under the car shows it. My less than fresh 89 vert handles waaay better than my 5.0s did back in the day. Chevy had to make up for that somehow and probably cut costs per unit on their engine. The Chevy's were great engines too and IMHO they sounded better than the 302s, hands down. I spent thousands on exhaust systems on my 5.0s to get them to sound good (and was left frustrated- favorite was the Flowmaster 2-chambers but that damn 2,000 rpm drone drove me nuts). The Camaros always sounded good. It was a fun time that is even more intense today!

dmccain

iTrader: (2)

The 80s-early 90s Mustangs, especially the Lx cars with 302s were lighter than the F-body cars to begin with. 305 TPI cars would outrun the AOD 5.0s most of the time and the 5.7 TPI cars certainly would. The 5spd LX mustangs were super-light and usually had 3.55 gears that made them hard to beat though. I hate that most of the time we hear Mustang guys beating up on F-bodys its usually an LG4 car, L03 cars or TPI auto-cars with a de-nutted cam and lazy 2.73 gears. I never lost to any stock AOD Mustang with my stock 91 LB9 car and it sported 2.73 gears. I could imagine what a 5spd 3.45 gear LB9 car would have done. I don't know because I never seen one at the track. The old HO 305 cars done pretty well though.

Tootie Pang

iTrader: (2)

And I'll bet you didn't even lose to that many manuals because it took skill to drive those. 5.7 IROC just mash that pedal down. I lost to plenty due to missed shifts or blown launches.

chazman

iTrader: (4)

I only raced one time with my '89 LB9/T5/3.45 back in the day. I was on my way to my girlfriend's, (now wife) and stopped at a red light next to an '88-ish. blue over silver 5 speed GT. He was revving his motor, figuring I was driving a peanut cammed, single exhaust, auto, 2.73, like most dealer ordered IROCs were and I would be easy pickings. I was determined to ignore him and not race.

The light turned green and he did a wholeshot and jumped a car and a half in front of me. In that instant, I said screw it and started to chase him down. My ear was exactly in line with his rear tire as he chirped it going into 2nd. I was reeling him in. By the time I was in 3rd, I was a car length ahead and we were going 90+ mph.

50 yards ahead the light turned red. I hit the brakes and stopped in time. My right front brake pad let out a puff of smoke. The Mustang GT simply did not have the braking power to stop and he ran the red. Thank God no one was killed!

I pulled up next to him a mile or two later and he wouldn't even look at me. He pretended to be talking to someone on his brick phone.

chazman

iTrader: (4)

Oh, BTW, that was my "turd" 305 which COMPLETELY blew away a 302..... LOL!

chazman

iTrader: (4)

Also, here's a short video my stock "turd" 305, which I ordered new and still own....

BonzoHansen

I dunno if I'd call an engine that was nearly bulletproof and was installed in countless millions of vehicle the biggest GM engineering blunder ever. Certainly it was a much more suitable engine in most of those vehicles than the old 302 would have been. The 305 wasn't a performance engine, but was designed to be one either.

chazman

iTrader: (4)

Exactly. Anyone here ever driven a '67-'69 302? I love the whole idea of an SCCA inspired engine, but nothing much is happening until you hit 4,000 rpm.

Even GM replaced it by 1970 so they could offer an auto trans and AC on the Z/28.

BonzoHansen

Solid lifter 2nd gens didn't get AC. I think it took until 73 for AC in a Z28. But that is certainly a side note and your point is on target.

dmccain

iTrader: (2)

Nice burnout chazman! That Iroc is no turd.

MY87LT

iTrader: (2)

To me the 305 is a great, sturdy engine with some performance potential. Granted, it's no 350, but it is a good engine and not a blunder. It served its purpose in the automotive world and we moved on.


Now, if GM would've continued on with their 302 engine, I feel it would have been the death of the all mighty 350 in cars and reserved for trucks.

Fast355

iTrader: (2)

GM had some way bigger blunders when it came to power in the 70s. The 262 & 267 Chevy, Oldsmobile 260, Pontiac 265 and the numerous 3.8 engines like 229 and 231 come to mind. GM also made a tiny 90* V6 with just 200 CID. I know years ago when I worked at an Autoparts house I once looked up a replacement engine for a car with the Pontiac 265 and the catalog simply stated, REPLACE WITH A 301. The owner put a 301 in the car and was back a week or two later looking for a TH350 to put in place of the 200 Metric. Oldsmobile probably had the biggest blunder with their 5.7 diesel that eventually also became a 4.3 V8 and 4.3 V6 diesel. Atleast the GM factory roller cam started with the diesels so some good came out of those boat anchors I guess. Then least we forget the sub 200 hp big blocks that were coming from all the manufacturers in that time period. Cadillacs engine dropped from 500 CID down to 368 CID in the same size of block and was only making 140 HP from 6.0L.

DynoDave43

iTrader: (11)

And let's not forget that lovely all aluminum cylinder liner-less lump in the Vega...technology just slightly too far ahead of it's time.

MY87LT

iTrader: (2)

They should have placed an aluminum head on top of an iron block instead of the other way around. That could have possibly solved the Vega's issue. Besides the horrible rusting that pretty much ate the car up.

chazman

iTrader: (4)

The funny thing is, I am so attracted to these "Malaise Era" cars. I'd love to get a 301 4 speed Grand Am or LeMans or a 305 4 speed El Camino or Malibu wagon.

MY87LT

iTrader: (2)

All right, I'm going to make GM shine here with everything they ever produced engine wise that has been called a failure.


The 1983 1/2 to 1991 Volkswagen Vanagon wasserboxer engine. Which was pretty much their flat four air cooled engine, converted at the last minute into a water cooled engine which leaked and failed like crazy especial when used with coolant that contained phosphorus.

Fast355

iTrader: (2)

I never saw a Vega but did get a chance to mess with a few Cadillac HT4100s in the rear wheel drive cars. They were HORRIBLE from a reliability stand point.

Fast355

iTrader: (2)

I ran against a Camaro Iroc-Z LB9 G92 car running 13.9s @ 101 one night. It had about 60k miles on it and the owner said it was bone stock other than a little fuel pressure and timing tweaking. He was iing the plenum and runners between rounds. He was running my class and I actually treed him but ended up breaking out. My 2012 Titan had been running 14.01-14.02 @ 97 mph on the dot but somehow pulled a 1.99s 60' and went 13.97 @ 98.

paulo57509

Yes. A 1968 MO/302 RS/Z28 with what is suspected to be the 1st design off-road cam (it was not a 30/30). You needed to constantly be in 1st/2nd gear to be in the fun zone.

But holy crap you could wind that thing for a while after the tach needle hit 7k.

Fast355

iTrader: (2)

OR....Do what the 1969ish Hotrod magazine article I read did. Put lower gears in it. They made that Z/28 run 12s with the single 4bbl, long tubes, deep gears and sticky for the time rubber.

I had a teacher way back in tech school that had taken a 283, bored it to 4.00" and had it in some old hot rod. Dumping the clutch repeatedly at 8,500 rpm. Had a hell of a scar to make you know the reason for trans blankets and scatter shields. Shrapnel cut him open and he lost several fee of intestine and spent months in a hospital bed. Guy is lucky to be alive and walking.

GTA1990

iTrader: (1)

may be as I'm a Brit and SBC's (of any derivation) haven't really been normalised here, but you put the stats of the LB9 with the L98 cam and T5 alongside contemporaries, and I'm not sure why it wouldn't be seen as a performance setup. It wasn't that far off the Porsche 911 of its day and there's a Motorweek retro of an early Z28 being slightly faster around a track than a Porsche 928

Sure today a milk float would probably take it...

zya5point0

iTrader: (4)

My biggest mistake back in 88 was buying the wrong car, lol! I had shopped for weeks, and even drove a couple 5.7 cars. Then I talked to my insurance agent. An 18 year old with a 5.7 car, get your wallet out! Almost twice as much a year! Got the 5.0 car instead, but wished I'd have shopped more and had more info. Looked nice, sounded cool, but only had a 2.73 rear. Beat some of my friends, got smoked by others. Only time I beat mustangs was when the guy driving missed third gear, lol! Yea, nowadays a 305 can be made to run pretty good, but nowadays there's soccer moms driving 400hp SUV's that'll smoke one. I know cause I almost lost to a Lexus once...

Fast355

iTrader: (2)

And 4,200+ lbs 4 door V8 sedans running into the 12s and beyond off the showroom. My buddies 5,000 lbs RCSB 8spd Hemi Ram went low 13s STOCK.

Jeremy85

Exactly why I'm learning diy turbo on my LG4 before swapping in more displacement. A Camaro losing to a soccer mom is a sin.

dragsta

the 305 in my TA is much faster than the 350 i had in my 1972 Formula firebird and it's a heck of a lot more efficient. if you can do a burnout like that in a car that will get good mpg, you shouldn't complain. headers and a cam should make it go even better.