302 chevy

[KeithTurk]

Re: 302 chevy

my 500hp 302 is a complete roller motor and has a Jesel belt drive... with Dart 230 heads... ( yep cast iron... gotta love it when wieght don't matter )... Carrillo rods.... so on

My 610hp 299 is an aluminum block wonder... ( I'm still wondering why the hell I did it ).... Dry sump, Kinsler EFI with a Motec controller... so on and so forth...

Oh and my old 2.8" Bryant Crank just made 685hp at 305cu in. when in SB2 trim.... ( Keith Dorton built it for a friend )

Keith

[min301]

Re: 302 chevy

A stock! 302 with the original 486 lift cam make about 375-400 hp so this may not be too far off. These 302's came with really good flowing heads so I would say it depends on how good the aluminum ones flow.

They were rated at 290hp (as was the Boss 302), likely for insurance purposes. A few years back, I was in the dyno room where we lit up a DZ 302 built to the original specs (pistons, cam, intake, carb... everything) for a complete matching-numbers restoration of a '69 Z/28. 360hp at the flywheel. The DZ 302 used the same straight-plug 2.02" heads as the LT-1 350. It was rumored that the angle-plug 2.02" heads (which were available over-the-counter) would add 10 - 15 more ponies.

And think, Vortec heads flow better.

[TC]

Re: 302 chevy

i found a 302 chevy that supposedly makes 500hp.

these are the specs on it:

The heads are alum D port heads, 60cc chambers with big valves. its got alum 1.6 ratio roller rockers. cam is a comp nastalgia cam, 298duration, 525ish lift with the rockers, was like a 2200-6900RPM cam. new valve springs keepers all that. Got headers that are wrapped up, alum weiland single plane high rise intake, 1 or 2 inch alum spacer plate and a 4bbl eldelbrock carb.

i know theyre not very specific but does it sound possible?

the guy said this setup on a 350 in a 79 malibu ran a 6.8 1/8th mile

Here's what I see, 60cc chambers with large valves, can you say serious shrouding. And what do they consider large valves??

Second 298 adv. duration on a flat tappet cam is like 230 .050 duration, and .525 lift, isn't going to get you a power range from 2200-6900 rpm, no way no how will that happen.

The manifold is probably ok, but the Edelbrock carb is a dead give-a-way that this motor isn't making 500hp.

Also what kind of pistons, because you will need a pretty healthy dome to get any sort of compression out of it. Because will a flat top you'll be looking at around 8.5:1. And that my friend will not get you 500hp.

As for the heads as long as they flow 240 or so CFM then they can support 500hp, but you have to have everything else matched up to do it.

[Eric68]

Re: 302 chevy

Stock DZ 302's did not make 360 HP, they made more like low 300's. There have been a couple bone stock Z28 Camaros that have been put on the chassis dyno that have put down 240 - 245 at the rear wheels. Back out 20% for drivetrain losses and you get just a hair over 300.

With a headers and the off-road cam they would get closer to that mid-300's mark. A good tuner should be able to get mid-300's out of one with factory parts and headers. This was a pretty hot motor back in the late 60's by the way. Geared right it would be tough to beat on the street.

The actual TransAm motors from Traco were dyno'd and made right about 440 HP. This was fantastic back then and nearly 1.5 HP per cubic inch. This was with state of the art (then) porting porting and real $$ behind the engine development program.

The mules that Kieth describes are VERY serious, and equipped with high end, high Dollar parts. Well maybe the Dart 230's aren't all that exotic but outflow even well-ported Camel Hump heads by a LARGE margin. Add in some other detail parts that are expensive (snappy roller cam and Jessel belt drive) and I can believe 500 HP . . . just not believable with the near-stock stuff in that 302 mentioned in the original post.

When you start looking at the 685 HP effort from 305" you can really appreciate the work that goes into something like that when you realize that there are much larger drag race motors much larger (like my 427 SBC, with some very nice parts in it by the way) that only make the same or a couple HP better than Kieth's 305.

[KeithTurk]

Re: 302 chevy

I've got the best 18degree heads money could buy and we're still in the 610hp range... to get the 685hp you have to get some SB2 stuff... and then you have to be willing to spin it harder by a lot... 9000rpm range junk...

and yeah it's all serious high buck junk to get to even 500hp...

I love my Dart 230's... they are to big for most efforts but flow like a Mo Fo for my little 302 and rock for the money involved... I think those things bare are like 300 dollars.... and don't take more then a grand a piece to make right with springs, retainers, machine work, and light clean up style porting...

If you need SBC heads they would be HIGH on my list for 23degree stuff...

K

[jcharliem]

Re: 302 chevy

Stock DZ 302's did not make 360 HP, they made more like low 300's. There have been a couple bone stock Z28 Camaros that have been put on the chassis dyno that have put down 240 - 245 at the rear wheels. Back out 20% for drivetrain losses and you get just a hair over 300.

With a headers and the off-road cam they would get closer to that mid-300's mark. A good tuner should be able to get mid-300's out of one with factory parts and headers. This was a pretty hot motor back in the late 60's by the way. Geared right it would be tough to beat on the street.

The actual TransAm motors from Traco were dyno'd and made right about 440 HP. This was fantastic back then and nearly 1.5 HP per cubic inch. This was with state of the art (then) porting porting and real $$ behind the engine development program.

The mules that Kieth describes are VERY serious, and equipped with high end, high Dollar parts. Well maybe the Dart 230's aren't all that exotic but outflow even well-ported Camel Hump heads by a LARGE margin. Add in some other detail parts that are expensive (snappy roller cam and Jessel belt drive) and I can believe 500 HP . . . just not believable with the near-stock stuff in that 302 mentioned in the original post.

When you start looking at the 685 HP effort from 305" you can really appreciate the work that goes into something like that when you realize that there are much larger drag race motors much larger (like my 427 SBC, with some very nice parts in it by the way) that only make the same or a couple HP better than Kieth's 305.

360hp at the flywheel. Saw it with my two peepers. Although, there was a pair of headers strapped on it in the dyno room. It's possible the mill was sporting the "off-road" cam that Chevy had available in the 60s over-the-counter, although I don't believe so.

[SpiderGearsMan]

Re: 302 chevy

q jet 9:1 350 motors make over 300 hp
they rated DZ at 290 hp , a good running one would be putting out 325 at 6500
maybe they had highway gears

[dulcich]

Re: 302 chevy

Work the calculus, brother. I cipher that a good 302 cube engine takes 7700 rpm to make 500 hp, and that's a fact you can take to the bank. If it ain't there as far as peak hp rpm, you don't have 500 hp N/A.
-dulcich (The Wise and All-Knowing Engine Master)

[jcharliem]

Re: 302 chevy

Work the calculus, brother. I cipher that a good 302 cube engine takes 7700 rpm to make 500 hp, and that's a fact you can take to the bank. If it ain't there as far as peak hp rpm, you don't have 500 hp N/A.
-dulcich (The Wise and All-Knowing Engine Master)

That's as vague as the original post. What's even better, is a stock DZ302 would pull to about 6,500rpm before nosing over. Wow, another 1,200 rpm and bang, we got another +150hp! I like it!! :

[dulcich]

Re: 302 chevy

Work the calculus, brother. I cipher that a good 302 cube engine takes 7700 rpm to make 500 hp, and that's a fact you can take to the bank. If it ain't there as far as peak hp rpm, you don't have 500 hp N/A.
-dulcich (The Wise and All-Knowing Engine Master)

That's as vague as the original post. What's even better, is a stock DZ302 would pull to about 6,500rpm before nosing over. Wow, another 1,200 rpm and bang, we got another +150hp! I like it!! :

No, it is not vague. It is reality, and pretty damned precise at that.
-dulcich

[Mr4Speed]

Re: 302 chevy

Stock DZ 302's did not make 360 HP, they made more like low 300's. There have been a couple bone stock Z28 Camaros that have been put on the chassis dyno that have put down 240 - 245 at the rear wheels. Back out 20% for drivetrain losses and you get just a hair over 300.

With a headers and the off-road cam they would get closer to that mid-300's mark. A good tuner should be able to get mid-300's out of one with factory parts and headers. This was a pretty hot motor back in the late 60's by the way. Geared right it would be tough to beat on the street.

The actual TransAm motors from Traco were dyno'd and made right about 440 HP. This was fantastic back then and nearly 1.5 HP per cubic inch. This was with state of the art (then) porting porting and real $$ behind the engine development program.

The mules that Kieth describes are VERY serious, and equipped with high end, high Dollar parts. Well maybe the Dart 230's aren't all that exotic but outflow even well-ported Camel Hump heads by a LARGE margin. Add in some other detail parts that are expensive (snappy roller cam and Jessel belt drive) and I can believe 500 HP . . . just not believable with the near-stock stuff in that 302 mentioned in the original post.

When you start looking at the 685 HP effort from 305" you can really appreciate the work that goes into something like that when you realize that there are much larger drag race motors much larger (like my 427 SBC, with some very nice parts in it by the way) that only make the same or a couple HP better than Kieth's 305.

360hp at the flywheel. Saw it with my two peepers. Although, there was a pair of headers strapped on it in the dyno room. It's possible the mill was sporting the "off-road" cam that Chevy had available in the 60s over-the-counter, although I don't believe so.

If it had the off-road cam in it you'd know it-they're really snotty-like a really rough 1000 rpm idle.

I love 'em!

[TC]

Re: 302 chevy

Work the calculus, brother. I cipher that a good 302 cube engine takes 7700 rpm to make 500 hp, and that's a fact you can take to the bank. If it ain't there as far as peak hp rpm, you don't have 500 hp N/A.
-dulcich (The Wise and All-Knowing Engine Master)

A good 302?? And are you trying to say, all you have to do is spin the motor 7700rpm and you'll make 500hp?? Wow if that's the case I want in on the secrets. :

Fact is you can make 500hp with a 302 at 6000rpm just as much as you'll make it at 8000rpm. It all depends on how the heads flow, the specs on your cam and the compression you are running, along with a list of other things. Your statement that all it takes to make 500hp with a 302 is to spin it 7700rpm is purely a fantasy. Can it be done, sure it can, but you can also make that same HP at other rpm levels and that's a fact. Basically there are just to many variables to make a statement like that.

[jcharliem]

Re: 302 chevy

There's a formula whereas a derivative of RPM and CID = HP? What have I been missing? Did "Volumetric Efficiency" and other factors in determining power just fade away? Maybe I missed that over the years. ???

[SpiderGearsMan]

Re: 302 chevy

my number was realistic

[SuperBuickGuy]

Re: 302 chevy

Math says lots of things, however, getting parts to operate in a manner that proves the math; is an altogether new game. Of course, the other problem with math is the numbers are never quite as accurate at describing the observed phenomena as we expect.