#21  
Old 09-13-2021, 01:26 PM
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Stan Weiss Stan Weiss is offline
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With what is going on not sure what anybody has in stock. But you might check with Butler.

https://butlerperformance.com/c-1234...l-pistons.html

Stan

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  #22  
Old 09-13-2021, 05:03 PM
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I've been running a 389 in my '65 GTO for the past 35 years without issue. Plenty of power and a blast to drive. Great engines, IMO. It runs better and harder than the '69 428 that was in it when I got it in '82.

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  #23  
Old 09-13-2021, 06:18 PM
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Default Runs Harder ?

"...It runs...harder than the '69 428 that was in it when I got it in '82."

NOTE: This is NOT in any way a put down, or a criticism, therefore should NOT be taken as such ! The poster was simply expressing his evaluation of the comparison of the 2 motors that were in his car.

But, that statement reminds me of TV ads that say a certain product is "best selling", or a "best seller", or "biggest seller, "or a "top seller". Well, does that mean it's better than all competitive products, or has sold more units than any competitive product, or does it mean that it is AMONG the best or has sold ALMOST as many as the competitors.

Or maybe a new movie is coming out, & the TV ads for it really play it up, saying that it's the biggest movie of the year, or the best movie of the year, or some other description that can't really be proven, since it hasn't even been released to the movie goers. They will decide which movies they like & don't like.

In my own experience, I've noticed that a LOT of guys have bragged to me about how great their particular car was & maybe how much power their engine had, etc. You know, the habitual bragger. It seems they think it's better, just because it's their's. Their attitude sometimes seems to be: "Everything I have is better than the stuff that others around me have." Most all of us have known & probably do know people like that.

Anyhow, back to the 389 vs 428 comparison. I have no doubt that the poster was giving us his honest opinion of HIS 2 engines.

Now, just for kicks, lets compare a 389 to a 428, NOT his 2 engines, but a 389 & a 428 BOTH built CORRECTLY for the same car, & for the same purpose.

Here are some comparisons I'd expect.

(1) At 2000 to 3500 rpm, the 428 will(should) have a lot more torque. This is probably the rpm range that most engines will see most often, for around town street cruising.

(2) Due to the extra low rpm torque, less overall final gear ratio should be needed, to maintain hwy speeds, therefore the engine can run at lower rpm while cruising.

(3) And, for those times when the owner wanted to get spunky, it should be no problem at all to build a relatively mild 428 up to at least 400hp, at probably no more than 5500 rpm.

I suppose it's real similar to how so many Pontiac guys recommend NOT building a 350, but recommend goin with more cubes. You know: "Bigger is better". It's just a fact. More cubes & stroke have certain advantages.

Can you build a good 350 or 389 ? Certainly. But, for several reasons, I recommend a longer stroke & more cubes.

This is NOT taking any core costs or costs to build into account. AND, it's just my own thoughts & personal opinion.

As always, opinions differ !

  #24  
Old 09-15-2021, 05:37 PM
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I would lower the compression in the 455 and run a 068 cam in it... However the 389 will run with the best of them. On the street I always liked the closed chamber

  #25  
Old 09-16-2021, 12:33 AM
Goatracer1 Goatracer1 is offline
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You don't need big valve or screw in stud heads for a cruising engine. Neither do you need forged pistons. If the engine was in reasonably good shape before it was pulled out you might not need new pistons at all. I'm a lot older than a lot of you. Back in the day we removed the cylinder ridge, honed the cylinders and put new rings in. We didn't have money for new pistons. We ran the original valve springs so we didn't need screw in studs either. Either I'm missing the point or some of you are. He said he wanted a cruising engine not a high performance engine. If that is true than he can build an engine that will last as long as he probably wants for a small investment. A stock 389 will have enough torque to roast the tires if that's what he wants. A cheap rebuild will last 30-40K miles with no problem. That would last me 15 to 20 years.

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  #26  
Old 09-16-2021, 06:04 AM
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Default Rings & Inserts ?

"...Back in the day we removed the cylinder ridge, honed the cylinders and put new rings in. We didn't have money for new pistons..."


Lol !

Yeah, the term that was used back in the old days was to put "Rings & Inserts" in an engine. Shade tree mechanics have been doing that for a long time, or at least they did back in those old days.

I've related here how that back in the winter of '82-'83, me & a friend I called "Cotton" put together a couple of 400 engines to power our bracket cars.

Removed the top ridge with a ridge reamer I borrowed from my Dad. Scratched up the cylinders with a ball flex hone, & put 'em back together with new inserts(bearings), rings, cam, lifters, & oil pump.

We ran high 13's that season. Both of us won races & made enuff points to go to the bracket finals. Cotton won the biggest race of the year at our local track, called the LA State Championship.
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  #27  
Old 09-16-2021, 02:30 PM
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geeteeohguy geeteeohguy is offline
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Quote:
Originally Posted by ponyakr View Post
"...It runs...harder than the '69 428 that was in it when I got it in '82."

NOTE: This is NOT in any way a put down, or a criticism, therefore should NOT be taken as such ! The poster was simply expressing his evaluation of the comparison of the 2 motors that were in his car.

But, that statement reminds me of TV ads that say a certain product is "best selling", or a "best seller", or "biggest seller, "or a "top seller". Well, does that mean it's better than all competitive products, or has sold more units than any competitive product, or does it mean that it is AMONG the best or has sold ALMOST as many as the competitors.

Or maybe a new movie is coming out, & the TV ads for it really play it up, saying that it's the biggest movie of the year, or the best movie of the year, or some other description that can't really be proven, since it hasn't even been released to the movie goers. They will decide which movies they like & don't like.

In my own experience, I've noticed that a LOT of guys have bragged to me about how great their particular car was & maybe how much power their engine had, etc. You know, the habitual bragger. It seems they think it's better, just because it's their's. Their attitude sometimes seems to be: "Everything I have is better than the stuff that others around me have." Most all of us have known & probably do know people like that.

Anyhow, back to the 389 vs 428 comparison. I have no doubt that the poster was giving us his honest opinion of HIS 2 engines.

Now, just for kicks, lets compare a 389 to a 428, NOT his 2 engines, but a 389 & a 428 BOTH built CORRECTLY for the same car, & for the same purpose.

Here are some comparisons I'd expect.

(1) At 2000 to 3500 rpm, the 428 will(should) have a lot more torque. This is probably the rpm range that most engines will see most often, for around town street cruising.

(2) Due to the extra low rpm torque, less overall final gear ratio should be needed, to maintain hwy speeds, therefore the engine can run at lower rpm while cruising.

(3) And, for those times when the owner wanted to get spunky, it should be no problem at all to build a relatively mild 428 up to at least 400hp, at probably no more than 5500 rpm.

I suppose it's real similar to how so many Pontiac guys recommend NOT building a 350, but recommend goin with more cubes. You know: "Bigger is better". It's just a fact. More cubes & stroke have certain advantages.

Can you build a good 350 or 389 ? Certainly. But, for several reasons, I recommend a longer stroke & more cubes.

This is NOT taking any core costs or costs to build into account. AND, it's just my own thoughts & personal opinion.

As always, opinions differ !
The 428 was a '69 360 HP with small valve heads, cast pistons, and too small a camshaft. Came in the car. The 389 is balanced and blueprinted with peened and polished rods (no China aftermarkets available when I built it in 1981) and fitted with a nice Sig Erson cam and valve springs. So the 428 was a low performance backyard rebuild and the 389 was a $2500 rebuild, which was a lot of coin 40 years ago. Drove this very engine today and changed the oil and it still runs great with 50k miles on it....although it's now starting to seep oil out of the cork gaskets. Valve covers have not been off this engine since 1981, and it powered my '66 GTO for 7 years, driving all over the country. Only downside is I used flat forged pistons, and with the cleaned up 77 heads at about 62cc, it needs race gas to run with optimal timing these days.

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  #28  
Old 09-16-2021, 05:06 PM
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This has been my experience too. I had a 64 389 with closed chamber heads. I ran Trips on it. I got a Edelbrock intake with three Holley's. It ran so strong. It had a four speed hydra-matic that really let that engine rev out of the hole, it had a 3.97:1 first gear with a 3:08 rear end... This was one of those cars that I put together with parts I had and my buddy's gave me to get it going. I just started Trade school and didn't have a whole lot of money.


Last edited by 389; 09-16-2021 at 05:15 PM.
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