The original 302's in 69 came with a 2x4 Crossram inside the trunk when the car was delivered to the dealership as the factory would not install them if that's what the customer ordered . Many were bought over the GM counters but most that I watched my pop build with 2 ..4's were the old tunnelrams .
I know a guy that has one of the old 2x4 crossram intakes. He scored it somewhere and was just hanging on to it. I was wondering about the guys that went .125 over on the 283 blocks and the guys who were doing the 301/302 builds pre-musclecar era.
Interesting quote from MotorTrend: Mark Donahue once told my father that the GM 302 was the best american made engine he had ever shifted on a road course. They lacked torque down low, but pulled great at high RPM.
Not starting anything here Ryan , just about to quote you numbers straight from GM here , anybody with an old Chilton's repair manual from 1964-1971 can double check the same numbers ? 302 / Produced in 1968 to 1969 11.1 : 1 Factory Forged Pistons w/ mechanical lifter camshaft Single 780 4 BBL Carb. rated at 290 HP @ 5800 RPM Also rated at 290 Ft. LBS. Torque @ 4200 RPM This is for those that know engines and where they build there horspower and when they start loosing it . If GM published these numbers correctly , the 302 built it's maximun horsepower at 5800 RPM meaning twisting that engine any further tha that RPM would mean that the car would pull harder if you changed to a higher gear getting the engine back in it's cam range for building more horspower . In other words , in stock configuration a 302 was done building it's peak HP at 5800 and pushing it any further than that was kinda like peeing towards the wind for the lack of a better term . Now all this aside , there were guys out there playing with those new "angle plug" heads and port matching some better intakes and playing with different cams that were twisting the snot out of these things and having a blast smoking some butts ! My pop used to zing his 9K + after it warmed up in his 57 Chevy and it sounded like it was about to come un-wound ! I was sitting in the front seat so I remember even with a "scatter shield" him making me put my feet and legs up in the seat just in case the clutch disc exploded . Now we took this thing out of his 57 and crammed it in an old Ford Anglia , what a freakin animal !!!! Too short a wheelbase though and it finally got crossed up one day and ate the ass end of a street sweeper . Can you make them run ? Hell yes ! Put em in a light car , you got a fun ride ! Bone stock off the showroom ??????? I already went there and should have worded it this way first ????? bore 4.000 x 3.00 stroke main bearing journal diameter 1968 / 2.2984-2.2993 rod journal diameter 1968/ 1.999-2.000 1969/ 2.4479-2.4488 1969/ 1.999-2.000
I can't speak to a showroom stock 302... I've never owned one. All I can really do is look to history (kind of our thing around here) and point to the amazing success the motor had on the track. Attached is an image of the Allan Green car... It's the car and team that mysteriously received the super rare cross ram intake in the mail one week... The result? 458hp and 7200 rpm.
Those Camaros would have been even more dangerous if the front suspensions from 67-69 hadn't basically sucked as far as sticking in the turns like thier competition did . But they made up in the straights ! I have some old footage I'm going to have to find and send you now of a race in 69 where the Camaro was pulling the front wheels in the straights about an inch and I aint talking about around a turn either ! You can clearly see daylight under both front tires about 20 feet out from the turn just after going into second !
I have also ben told by an old GM mechanic that the 290 'advertised' hp was a wee bit on the conservative side.
Ive owned a few 69 camaros, and yes the DZ302 are rated at 290 hp for insurance purposes, like the ZL1 427 was rated at 430 hp, it has been dynoed at much more than that... The DZ mill made more like 350hp, and correct me if im wrong but I think Dz 302s are large journal, and if you build a 302 with a 327 block and 283 crank its has to be a small journal... And if you really wnat to build a screamer put a 350 crank in a 400 block, trust me it a fun lil mill at 377ci
Factor HP ratings were a joke, 290 is the joke ,and 5800 rpm is the punch line. 6500 would be more like it. No doubt the 302 chevy filled the hole GM needed to go class racing, and it did a damn good job. This day and age I would go for cubic inches and lower RPM's. I just like to drive my cars to much to use a high rpm combination with deep gearing. Maybe getting old?
I am in the process of restoring a factory Trans am 302 right now. the retired GM engineer that is helping me on the rebuild said that they were under rated for insurance purposes as well as what they wanted the competition to know out of the box and straight to the dyno they would regularly produce 350 to 400 hp at 7000
Good thread camarokid. I have a '29 roadster with a 301 in it. A 283 bored .0125..big heads..balanced and blue printed..aluminum flywheel with a 650 double pumper. Has a 4-speed muncie with a 9 in. ford and 3.89 trac-loc rear. This should be a 2000 lb. car or a little less.If I can get my big arse in gear it should be on the road this spring. Do you wanna come out and play!!!
ne again , not starting anything here and not saying any of yalls numbers aren't correct but I have a buddy named Ron Schul that worked for GM in the engineering and testing dept. back in those days and he's still a racing buddy of mine today . I drive his cars on Nitrous because his reflex actions are too slow . He has told me several times that the highest numbers he ever saw while testing 302's , and he tested many of them , was in the 315 to the highest being 325 playing with the valve lash and carb tuning . He also was lucking enough to test everything that rolled outa the assembly line back then too and he was the one that also put the term "terds" in my mind and I never forgot it . All I can say is he's a straight shooter when it comes to numbers because he is a serious engine tuner for some serious engines to this day and every HP he can get counts in his books . But like I said , headwork , cam selections , and carb. playing can get those numbers you are talking about but GM would only let those engineers play with GM parts for thier documentation numbers . The Govt. didn't get real shitty with the big 4 until the mid 70's and that's why everything went to hell in a hand basket with compression and HP in 1971 .
Here's what Vince Piggins (lead engineer behind the z28) told Hot Rod Magazine in 1971: Coincidently, HRM dynoed a factory stock Z28 with a dual four that same year. Their dyno saw 403hp at 7400 rpm. That's a bone stock 302... I think people's experiences may vary in the real world, but the 302 certainly has history on it's side as being one of the most impressive small blocks ever built. The little motor won almost 80% of every TransAm race and Super Stock race it was entered in between 1968 and 1969. In fact and according to GM Performance, it has the highest winning percentage of any American motor... Ever.
The 302 was AWESOME...and still is...and will always be AWESOME... a really good runing engine and combination from GM....and it made good power....E.C.
These cars were so successful 67-69,so they obviously built small and large journal 302's (?). Check out the vinyl roof,on a couple of them. Now lets get back to Traditional hot rods,before someone objects to this thread. Thanks for the tolerance guy's.
I think we all mostly agree that they were and still are considered a GM "BAD BOY" of that era . In TransAm racing , the cars were totally gutted with nothing but a light cage and I agree that they did VERY WELL considering all factors put into place . Maybe I should have said , "yes those are some bad ass little engines , but stick them in a 3,200# 1968/1969 Camaro with the factory single 4 BBL in place , and they got smoked PLENTY just because of the torque to weight ratio being the lessor combos available off the showroom floors . Anybody know the true numbers put out by a 375 HP 396 / 430 HP 427 / 450 HP 454 ????? I think those numbers will put everything into perspective when you research those other GM "BAD BOYS" also but yes I agree , per cubic inch , the 302 was a bad little dude , bar none ! Hell , it's a Chevy ....I love it anyway !!!!!!
For starters have you ever even ridden in an original SS Chevelle 396? I must disagree. Matched with the factory 4spd and the right rearend that engine would require you to drive with two pairs of underwear. The car I know, gets 4th gear rubber and serves a whiplash dessert. It's a factory engine numbers matching all original equipment except for the rear gears. I have raced 327's with my 400 horse 350 and they have kept up but, they can't rev high enough so when they are shifting my foot is still on the floor rappin it up.
302 is a great engine. You can build a 377 (400 block, 350 crank) or a 383 (350 block 400 crank) for the same $ and be much better off. 302, 377, 383 will all have to balanced. If you have a 283 or 327 build it with the rotating assembly thats in it, save the $ of having to balance it. a 6Krpm 327 makes a lot of power with new cam technology. a valvetrain to support 8Krpm and above is expensive. pre 1967 all came with small journal cranks, except for the camaro only '67 350 had a large journal. 68 and beyond had large journal cranks Ive built both large and small 327's and really dont see a difference, it just depends on what block you have. you can discuss bearing friction differences or crank rigidity for either case but at a street/strip level of build youre not going to notice a difference.
My highschool car was a 1970 SS 396 Chevelle and the only guy that ever beat it was a 396 Nova because he had a 4:88 gear with a 4 speed and 50's on the ass with a heavy azz Dana 60 helping with traction because there was 400 pounds of Mopar rearend sitting on those 50's plus the rear weight of the car . I won't get into any weight transfer advantages on the Nova since the 50's stuck out of the rear quarters about a foot and the ass end was up in the air like a Jack Rabbit . All I can remember clearly was seeing tailights for about the 1/8th mile mark until my Chevelle finally hooked up and my 3:36 gears started kicking in and flying past his ass right at the end but he did win . He also had to go back down the road and pick his driver's side door back up that sucked off the car when my SS went by ! I may have stretched the door part but the rest was dead on !
One thing I've noticed-most people gain wisdom as they age. I'd take a low compression, low-rpm, big-inch smallblock over a smaller displacement, high compression, high rpm screamer any day. 11.0+:1 smallblocks with iron heads just will not run on today's gas. I had a 64 Chevelle convertible with a high-compression 283 back in the 80's and had to back off the initial timing to keep it from detonating itself to pieces at part throttle. Guys, it ain't 1964! The pump gas available now won't run those old-style engine combinations. The technology available now is far more advanced. If the tuners "back in the day" had the parts we have now, do you think they would want a big motor with Dart heads, or one of the small-displacement motors that seem so popular with some people on the board?
Ditto ! 434 cube SBC with 9.5 to 1 , Brodix aluminum heads , runs on Super unleaded , my only screw up , grouted the block for strength which made in pretty much suck at a long stoplight . Other than that tiny screw up , Hyd. roller , MSD ign. , drive it anywhere and bust some serious ass and drive it home and sounding "FAIRLY TAME" the whole time although anybody with a brain that pulls up next to it knows you have a powerplant ready for doo-doo time !
i live in england so we dont have any truble with gas! i can bye 98 octane all day long strate out the pump!
I think the biggest problem for a 302 vs. bigger engine is the driver. A 302 live on rpm, and if you let it fall off the r's, you are done. Like a 2 stroke. 400 hp is 400 hp, no matter the size of the engine. But-if you have a 2000 rpm window to make that power(BB) vs.1000 (SB) or less (I'm just guessing here), it is EASIER to go fast more often. Horsepower is great, but torque moves the world.
Not to take us off track, but I just pulled a 307 out of my '54 Belair. I ran it for nearly 15 years, put maybe 10k miles on it. I loved it! I never dyno'd the car, but I would be very surprised if it didn't have at least 300hp. It pushed my boat anchor '54 down the road at a real quick pace, with 3:73's out back. The thing I loved most about it was the reliability factor. That car would sit, sometimes for several years, and it would fire right up and run great. I doubt this is the "revy chevy" since it seemed to me that power peaked about 5600-5800RPM. All that aside, this was a very fun and very reliable motor.
when i was running my dragster in the 50s ,my eng was a 283 bored to 4'' stock crank and rods with a set of jocko heads a 6 carb intake with the 2 centers blocked off. we ran 10.70s at 127 like a bracket car. this was in a home built 98'' dragster with a olds r/e. rpm was unlimited with a herbert roller. no tach.
LMAO @ Ryan ! What ever we do , don't get a Ford vs. Chevy thread going or the page will go to shit for weeks ! LOL Belair ...you are 100% correct though ! Too many people put too much stock in HP and not Torque ! That's why the new breed of drag racing for the last 10 years is bigger cubes , less gear , and power adders wether it be Nitrous , blower , turbo charged , etc , ! Still got a kick outa Ryan's comment !!!!
You guys are certainly talking about two completely different engines here. I'm not an expert by any means, but I watched my friends build 301's out of 283's (maybe it was 265's) in the early 1960's.....and I watched the 302's developed for the TransAm Series in the late 60's in the Camaros....Two totally different animals....maybe that's where the argument is coming from....If you decided which engine you where discussing, maybe the thing would become clear....In my book, neither one was a bad engine....if they were, there wouldn't be so many fans..... Yesterdays engines nearly always become "bones" to somebody sooner or later.....Sandpiper
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