I was thinking about putting a 327 in my fiero but i have found a chevy 302 that i might can pick up for pretty cheap. the thing is, i dont know much about the 302 except that it is rare. i was wondering if anyone can tell me which is right for my needs and which would be cheaper to build up.
What i am wanting is a high revving motor that will be strong enough to hold boost when i put a supercharger on it. Also how much power can the getrags hold?

If that's an original DZ 302 it is worth a lot to restorers. Sell it and get a clone.

I drove a early z28 302, and was suprised (at the time) at it's abslolute lack of low end performance. The fella that owned it suggested that I "get on it" . At about 3grand ya had to hold on or you could be in trouble. I suspect that in a Fiero, that you'd be tempted to do power shifts, and without a LOT of experience
I suspect that you'd lunch the transmission of the Fiero. The 327 (in my estimation) would be a far better choice.

Don't know too much about the 302, but the getrag if built right can hold quite a bit. The internals seem to do ok with lots of torque, but the case will likely crack with too much power. Talk to California Kid, he had his getrag cryo treated, making it stronger behind a high powered vet engine.
The other problem is breaking axles, you'll break axles with a high powered v8, let alone a supercharged one. The problem I've read is the CV joint? Cali kid is working on some possible custom axles last I read.
All in all, no rebuild for the Getrag with a supercharger, or custom axles will result in pieces everywhere.
If you found me helpful, add a plus please, thanks.

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1986 Pontiac Fiero GT
Auto, soon to be 5 spd Getrag from 88 z24, Best 1/4 = 16.1 at 83mph, mods, wires, CRX intake, and power pulley. Planning Turbo 2.8 swap for a little more umph!!!!

Bought for 2500$ Canadian.

Some info on the 302: Small journal crank, 3 in. stroke, 4 in. bore, forged crank, forged rods, too much compression of todays gas (64cc), heads will require hardened valve seats installed. Weak point is the rod bolts. If you supercharge this you will need to change pistons. If NA you could get some later heads with large chambers. How are you going to find room for the supercharger drive belt?

If it is an original DZ 302, it will have something like 13.1 compression. I would get it cheap, sell it to a camaro resorter for a huge profit and build a latemodel 302 clone.

Here is how the clone is built:
4 bolt roller cam 350 block, LT1 4.3 crank (3" stroke) and PM rods (these are a custom length), and 350 LT1 pistons (4" bore). Thow in a solid roller cam and a set of vortec heads and you have a very potent 302 clone that should have much better dirvability than the older version. And if you frag the thing, or the car gets stolen you haven't been robbed of a real DZ engine.

Can you mix LT1 and Gen I 350 parts? It's my understanding that you can't.
But you can use the 4.3 crank in an LT1, I know that works.

I have to agree with others, if it's an original DZ motor it's worth far more to a collector. I wouldn't use such a rare motor in anything other than what it came in. Sell it for big bucks, then build whatever you want.

If it's not a DZ motor, are you sure it's a 302 and not a 307? Or even a 305? What year is it?

Is there a particular reason you want the 302? ie, vs some other SBC? ie, vs it's more common (but externally identical) big bro? There is NO weight saving, you may have a bit more trouble finding parts altho probably that will only come out in having to pay more (simply far less volume on this motor)..... for any parts that are specific to it alone.

The 350 is the EXACT same block; just with a slightly bigger bore; has essentially the same crank (o'all dimension and weight-wise; don't get concerned about stroke!!) and has TONS and TONS of stuff avail for it. There are loads of them around and every possible sort of speed equipt available for it. (translation: stuff is CHEAP). You can buy performance pistons, valves, springs, cams, oil pumps, bearings, gaskets, intakes, alum heads, etc etc etc for peanuts. There are lots of prescription-based performance buildups; Edelbrock has one combo for a 'STREET' 350 that is ~420 hp. Simply buy and bolt on their parts and presto!! Or anything in between. NOBODY but you will know that you have a 350 vs a 302 if you don't want. So I would go for the more common and bigger 350. It is, after all, what Chevy ended up with..... they discontinued the 302......

Honestly, there is a ton of misinformation in this thread.
The 302 originally came with 11:1 compression pistons which is obviously not a motor you'd use boost on.
This motor was originally designed to compete in the old Trans Am races when there was a cubic inch limit. This was a screaming high rpm engine and that's why you build it. If you have a heavy car that needs lots of torque then obviously this is not the engine for you but if you have, say, a light Fiero with a really low geared Getrag trans then you could really have something interesting. I have always wanted to have one of these in my own Fiero but with 11:1 compression, a 800 cfm carb, and the lumpy solid lifter "Duntov" cam that they came with stock, it's just not something you could drive everyday so easy.
These sweet little engines came stock with forged 11:1 compression pistons, forged crank, Holley carb or a very rare cross ram two four barrel carb set up, the big lumpy "Duntov" solid lifter cam, "Fuelie" heads with 2.02/1.60 valves, and a host of other goodies that made this rare little engine absolutely scream even in stock form. This pushrod small block, even stock from the factory, could easily reach 7k. They laughingly underrated it at 290 HP but most sources say the street stock engines were between 300 and 350 HP. They fooled people by using a lower rpm to rate the engine because Chevy really didn't want it to sell much. At the time, the rules of the Trans Am races stated that you had to sell so many of these things on the street in order to qualify the parts for the race and that's pretty much what it is, a thinly desguised road racing engine. Very much like the S2k only with more torque and lumpy idle. I have an old magazine reprint that jokes about how the 302 is like an angry dog pulling and tugging at the end of a short leash. Insert Tim Allen grunting here _____
The 302 powered Camaros dominated the Trans Am races in 68 and 69 blowing Fords butt right off the track. The Traco built 302's in the Trans Am race cars made 450 HP!

The 302 was only available in the 67(only 602 made), 68, and 69 Z28's. There was no other motor available in the Z's of those years. They came standard with a 3.73 posi rear end and that was the highest rear gear you could get with them! This is a rev motor after all. Optional gear ratios were the 4.11, 4.56, and even a 4.88 final drive!
You probably can't tell but I like this motor.
327 block + 283 crank = 302
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Activities Director N.I.F.E.

www.fierofocus.com

[This message has been edited by Dave Gunsul (edited 12-04-2004).]

quote Originally posted by Dave Gunsul: Honestly, there is a ton of misinformation in this thread.

Thanks for the corrections, Dave!! I knew it was 1st Gen Z28 only but not much else.

Dave is right.

The 302 was made for high rpm power not low rpm torque. A basic rule of thumb is More stroke= More low end torque capability. Less stroke = High rpm capability.

I've read a little on the 302 and am entertaining the idea of getting one for my next fiero project. Just as Dave said, it's a perfect engine for a fiero. Light car, low geared. From what I've gathered so far, the 302 is a 350/327 block from the 67-69 era. The block has smaller main journals. They are the same size journals as a 283 and the engine uses a 283 crank, thus a shorter stroke.

My question is, can the smaller journals take the power just as reliably as the bigger journal 350? I've been meaning to get a hold of SCAT to see if it's possible to make a 283 crank with larger main journals to fit a modern 350 crank. I already have a set of rebuilt vortec heads and a retrofit roller valve train set up to fit in where a flat cam used to be.

As far as the high compression goes, I'm not planning on using the original heads, so I'm sure that 11:1 CR would be far less. Thus opening it up for the possibility for a turbocharger/supercharger.

Soelasca hit the nail on the head, the Chevy 302 was a high RPM motor.
The reason I did the edit was to add with the Fiero's man. transaxle. The 1 gear is really short and 2nd isn't much better, so a high RPM motor would help, and in a Fiero you really are not going to need alot of low end torq.!

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Bobby from NW Indiana
93 Northstar and 5 speed Getrag
thespeedshop@sbcglobal.net
My build thread

[This message has been edited by GSXRBOBBY (edited 12-04-2004).]

quote Originally posted by Formula88: If it's not a DZ motor, are you sure it's a 302 and not a 307? Or even a 305? What year is it?

It is a 302 from a '68 Z28

Just my opinion, but with the parts available today (and many have been available for a long time), why now have the best of both worlds with the 350 ??? Sure, you can build up a 302 to perform, but you will not have the low end torque that puts the competition away quickly. The 302 was a deadly engine, but anyone who has run against them, like myself, knows these cars did not start accelerating hard until they hit 3rd gear (near the 70 to 80 mph mark). The point I'm trying to make is that your pleasure is only going to be at high speeds, because it isn't going to get out of the hole too quickly.

My modified TPI setup will pull hard to 6,200 before it noses over (and it noses over hard, like a rev limiter), which is fine with me, it could rev higher with a different intake setup on it, but also induce the risk of more wear/tear with higher rpm. The 350's can rev, it's just that not many people have gone with those modifications.

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Car History: https://www.fiero.nl/forum/Forum1/HTML/025670.html

i may just see if i can buy it off of him cheap and sell it for a profit to fund another motor. im not planning on doing this in the next couple of months but maybe in the next year or so so i have some time to make up my mind

Ah, those old 2.02 Fuelie heads -- I remember when I bought my first and only set for $50. You really took me back there (to 1977) ...

The thing a lot of you forget when you're talking about the 302 and running against it is that it was in a much heavier car with higher gears. The Fiero is light with much lower gears. Think about it for a second now, all that torque some of you are going on about is lost in tire smoke with that low first gear. A high rev motor makes it's power higher up so it not only has less spin but also holds that first gear longer! The cars the 302 came in were 35-3700 LBs!!
Even with the so called low gears they came with, they still aren't as low as the getrags first gear. I find it ironic that some of you that are arguing about having torque are the same ones i've seen talking about having to start off in second gear because you can't use first. Now before anyone gets their panties in a bunch, i'm not flaming anyone or even upset in any way but seriously, think about it for a second here. There is no such thing as the perfect combo or engine choice but we're talking about the torque, parts availability, and reliability of a sbc yet it can rev like nobodyies business. Sounds like a cool choice for a sportscar to me.
Maybe it's not right for everyone but it might be right for some.

BTW when i'm talking about low gears, i'm not just talking about the final drive. You have to take into account the first gear and final drive together in the overall ratio. The old Muncie trannies that came behind the 302's had, at best, a 2.20 first gear and a final drive of 3.73 (standard was 3.73 on Z28) where as the Getrag is a 3.61 final and 3.50 first gear. That's waaay lower obviously.

Also; the journals were increased in size later on if i'm not mistaken. I believe (on memory) that the DZ block/engine was the one that had the larger journals but i'm not 100% sure on that one. Also remember, as far as power handling goes, the race engines put out a minimum of 450 HP as i listed above.

quote Originally posted by Dave Gunsul: The thing a lot of you forget when you're talking about the 302 and running against it is that it was in a much heavier car with higher gears. The Fiero is light with much lower gears. Think about it for a second now, all that torque some of you are going on about is lost in tire smoke with that low first gear. A high rev motor makes it's power higher up so it not only has less spin but also holds that first gear longer! The cars the 302 came in were 35-3700 LBs!!

No offense taken Dave........but I think your approx weight is in error on the Camaro, if memory serves me correctly, these cars came in at the same weight as the Fiero, 2,800 lbs.

Secondly, it is a misconception here on the Forum that a high powered V8 Fiero puts the tire up in smoke on a hard push. That might be true if your running cheap hard, narrow tires, but I certainly haven't experienced it on the street with my setup. As a matter of fact, I just spent $1,600 for custom built half-shafts, because I torque shear the Mark Williams Racing Splined axles every two seasons, the traction is that good with the mid-engine setup. Sure I can put my tires up in smoke intentionally, but that's not how you drive when racing. Now that may be a good reason to go with a lower torque V8, but I went for the Cookie Jar, it's just a matter of preference. As I said earlier, you can build a 350 to be a high rev engine with lower torque, and you don't have to give up the cubes (blocks are nearly the same weight anyway).

Take a look at the power curve on this setup:
http://proformanceunlimited.com/specs/350_420drop.html
The hp doesn't drop off below 400 hp until it hits 9,500 rpm

[This message has been edited by California Kid (edited 12-05-2004).]

The Camaro has never been 2800 LBs.

I do agree that the 350 can be made to rev certainly but not quite as well as the smaller engine can. All things being equal, the larger motor will make more power obviously but the smaller motor can appeal to someone that wants his powerband higher and/or in a different way. There's a lot of reason someone might prefer the smaller motor over the larger and vice versa. I was merely pointing out the reasons someone might prefer the smaller motor over the larger.
The tire spin issue may not be one you yourself have Calikid but some do and i've seen quite a few threads talking about starting off in second gear because first is to short for the V8 posted by V8 owners. The 302 is a high rev motor from the start, it would be very well suited to the Getrags low gears and the lightweight of the Fiero. It's a good fit for some, maybe not everyone, but some. Some want more cubes and torque but some may want to be able to rev to the sky while still having a sbc. Not to mention being different.
The smaller motor, given the same components, will always be able to rev better than the larger motor with the same components. The larger motor, given the same components, will always make more power than the smaller.
I'm glad you didn't take any offense, I didn't want to make it seem as though this is a heated argument between us. I certainly have nothing against 350's after all but the 302 is my favorite engine of all time. Bar none. It's a wild little no compromise engine that can rev and yet still has torque and the only sbc i've ever read about that is compared to a V12 in sound when it's reved up.
In a light car with low gears with it sitting right over the tires, it'd be a lot of fun i think.

[This message has been edited by Dave Gunsul (edited 12-05-2004).]

quote Originally posted by California Kid: Sure, you can build up a 302 to perform, but you will not have the low end torque that puts the competition away quickly.

The thing is, it's still a blown V8 in a fiero. It will still have plenty of low end torque. Besides, low end torque puts a lot more stress on drivetrain components than high end power. durability is a major reason that i want to have the power band higher in the rpms, not as much the motor but everything else. im already hard enough on transmissions and axles anyway.

Dave, I stand corrected on the weight issue, should have done the search before making that comment:
http://www.familycar.com/Classics/69Camaro.htm

The only negative I can think of is the availability of good quality high test gas.

I used to run a 10:1 car and when unleaded came along, even the 94 Octane was not enough. I ended up having to retard the timing at that time.

An 11:1 sounds like a bit of a headache unless you use additive on every tank or know an air port owner

The lower initial torque from idle won't even be an issue from what I can see. The first gear will still have all it can handle. The big + to me is the power over 6,000 rpm which will mean the car will be fast, fast, fast.

I'd say though, that if the engine is valuable and you can sell it for a good buck, an SBC swap might put you $'s in pocket on the deal and for all intents, will work about as well.

Good luck either way.

Arn

Well, I would definitly like to do a 302 fiero, just for the experience of building a 302 and seeing how it stacks up against my 350 fiero....uhhhh...which isn't done yet.....uhhh....yeah

One project at a time

quote Originally posted by huffstud106: It is a 302 from a '68 Z28

In that case, I'd definitely sell it to a Z28 collector who needs an original '68 302 motor. It will be worth more to that person and you'll get enough from the sale to build whatever you want with money left over.

A note about bearing sizes. Someone asked if the smaller bearings could handle the power. Use a forged crank and you should be ok. While larger bearings do increase crank stiffness, they also increase bearing drag, which is a bad thing on a high rpm engine. Race engine builders routinely turn the crank journals as much as possible to run as small a bearing diameter (both rod and main) as they can get away with, because less friction means more revs and more power.

[This message has been edited by Formula88 (edited 12-06-2004).]

quote Originally posted by Formula88: A note about bearing sizes. Someone asked if the smaller bearings could handle the power. Use a forged crank and you should be ok. While larger bearings do increase crank stiffness, they also increase bearing drag, which is a bad thing on a high rpm engine. Race engine builders routinely turn the crank journals as much as possible to run as small a bearing diameter (both rod and main) as they can get away with, because less friction means more revs and more power.

302's came stock with a forged crank.
I also looked up the bearing thing; the bearings were increased in size in the 68 model year not the 69. The 69 DZ block had 4 bolt mains while the 67 and 68 302's had 2 bolt mains.

this last post of dave's just added the last bit i would have wrote. he's just about covered it. if you're looking for more info there is a book that pops up on ebay off and on titled something like "302 and 327 chevy". it has a lot of the old hot rod mag. articles from when it first came out, including some hop up articles.

it's an engine i'm interested in, and have a few parts collected up for also.

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Phil T.

start where you are,
use what you have,
do what you can. arthur ashe

Formula88 - it is not advized to swap LT1 rotating assy parts (pistons & cranks) with pre LT1 parts because the LT1 stuff is much lighter and balancing will become an issue. An older 305 crank is closer to the counter weights of a 350 LT1 than the pre LT1 350 is.

However, if you take the entire LT1 rotating assy (crank & pistons from LT1 350, and rods from LT1 4.3), then the assembly should balance without much issue). This rotating assy is a direct bolt in to any pre LT1 1 piece rear main seal.

Just an idea of what the 302 engine is worth. Twenty years ago I sold the one from my best friends totaled Z for $1500.00. That was just for the long block. I sold the 2x4 intake and carbs a while later for $2000.00, had a new baby on the way. I bought the entire setup from the local salvage yard for $350.00 after my friend wrapped it around a tree. They didn't know what they were selling until it was already loaded in my trunk. Boy was the yard owner pissed at the counter man. Wish I had it back, it would be in a Fiero so fast my head would spin. No matter what anyone says it would be faster than any 350, I had that 302 installed in a 76 Chevy Monza and it was scary fast. Lord I miss that car.
Rich

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Rick Longfellow
Formulagator
fierorick64@earthlink.net
rlongfel@ufl.edu
88 Formula 3800 SC 5 speed
84 SE 2002 2.2L 5 speed
85 GT 3.1 Auto

quote Originally posted by Philphine: this last post of dave's just added the last bit i would have wrote. he's just about covered it. if you're looking for more info there is a book that pops up on ebay off and on titled something like "302 and 327 chevy". it has a lot of the old hot rod mag. articles from when it first came out, including some hop up articles. it's an engine i'm interested in, and have a few parts collected up for also.

To add to this post about information reguarding the 302; you can also look into a book called Camaro Untold Secrets, The Great Camaro, or Brooklands Road tests for the 67-73 Camaros. All three of these books have good 302 info but the Untold Secrets one is absolutely flooded with info on them even including dyno charts from back in the day. They even cover the experimental aluminum heads that were never used unfortunately.
I have all three books.

[This message has been edited by Dave Gunsul (edited 12-06-2004).]

quote Originally posted by California Kid: Take a look at the power curve on this setup: http://proformanceunlimited.com/specs/350_420drop.html The hp doesn't drop off below 400 hp until it hits 9,500 rpm

That's some BS right there... no $4800 Chevy is going to rev to 10.5...

On the modern 302's...

The combo is L99 crank AND L99 rods with 350 pistons. This combo can be used in ANY large journal small block with the appropriate rear main seal. The assembly must be rebalanced no matter what because the 350 pistons will be heavier than the L99 pistons. An 11:1 350 piston will give about a 9.5:1 302. The L99 rods are 5.940" long, which allows use of pistons with 350 compression height.
That's the cheap version.

If you want to build stout, get pistons for a 383 with 6" rods and get some 6.375" conrods for the 302. The L99 crank is considerably stronger than the LT1 crank, so it's good for quite a bit more RPM. You shouldn't need a forged crank unless you go really wild.

If you want a really cool 327, get a 400 block and punch it 0.040 over (4.165), then use the 3" crank in it. With pistons for a 400 with 6" rods, you can again squeeze in 6.375" conrods. Big bore short stroke long rod (BBSSLR) 327. This one also has the advantage of the bigger bore allowing bigger valves in whatever heads you pick...

Sounds like the info I'm gonna be needin' in the future will.

thx

you can get out of the hole fine with a 302 in first gear. any real drag racer will tell you that I've seen a 69 camaro with a 302 that had a dominator 750carb and 4.56 gears in a gutted car run mid 10 sec 1/4 times with a 1.4 60' it was a 4spd munci car

the 3in crank will hold fine. most guys building high rpm bigblock chevys have the journals turned down to small block size and same with a lot of high rpm 400 or stroker combo's. the cranks usualy brake in the webing between rod and crank journals not at the journals. also the shorter the stroke the less stress that is aplied to the crank so it allows it to hold more hp. that is why more race engines go with the big bore small stroke combo. check out pro stock engines.

if you droped the $ for some flat top two valve relief pistons it would drop your compression to 9 to one with a zero decked block, and felpro .040 gasketts they are realy strog engines.

347's rock...
Iron heads? Prolly coulda gone higher than 10:1 and still run on pump gas...

I think your best bet is to buy the DZ 302 cheap and sell it for big bucks. Take the profits and build the motor that Fieroguru and Will are talking about (I've been thinking about this for my next project). You might even have enough left to pay for an Archie kit. And I'd look at turbos rather than a supercharger, but that's just me.

Also, One benefit that Dave Gunsul eluded to about this motor that has been missed here is not that just have lower torque makes first gear useful again, but the higher redline also makes it more useful. Torque is simply a function of throttle application. I have a ~6,300 rpm rev-limit on my car and I hit it at about 20 mph in first. Yes, I can launch in first gear without spinning the tires (this takes some practice), but I barely have the clutch all the way in before I need to shift. Having to shift can realy hurt your acceleration numbers, so I usually start in 2nd because of that and not because of tire smoke.

Huffstud106,

Good luck getting that motor and keep us posted on your progress

Later,
Troy

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The 1st LS1Archie car

The guy "comming out of the hole" is exactly what I'm talking about. Ya can't just let out the clutch. Ya have to dump the clutch, and I suspect the Fiero tranny is gonna ***** about that.

That's exactly wrong. Dumping the clutch is entirely un-necessary. Using good technique and feeding the clutch is the proper way to launch a car. I've got the timeslips to prove it.

DAVE,
YOU ARE 100% RIGHT. i'VE BUILT AND RACED many many CHEVIES for many years. And the 302 was one of Chevies best motors ever. Now for the Fiero, fuel injection would be the answer to the gas problem. If I was putting a V8 in a Fiero, the 302 would be the ONLY choice.

quote Originally posted by Will: 347's rock... Iron heads? Prolly coulda gone higher than 10:1 and still run on pump gas...

I have alum. l98 heads and is is realy a little over 10.5 but I was in a hurry earlier they are 58cc chambers and the block is zero decked 30 over block. .040 felpro gasket thanks for the thumbs up on the engine choice. it is built for spray but the transaxle didn't like the engine it should run low 11's on motor I'll let ya know. but the short stroke is nice in a fiero.