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Old 07-30-2020, 06:19 PM
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Hooter Hooter is offline
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Default ‘68 428 Engine 0.090 Over

Mutual friend called asking if I’d be interested in a 428 that he claims is .090 over bore. I haven’t seen the motor yet(been sitting in a car for 20 years) but curious how far some have taken these 428’s. I can get it pretty cheap I think, but curious if I’d be buying a parts engine if the cylinders have any rust from sitting and it needs cleaned up again. Supposedly has ram air 4 heads but I’ll believe that when I see it.

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Last edited by Hooter; 07-30-2020 at 07:13 PM.
  #2  
Old 07-30-2020, 06:38 PM
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The only way to know if that block could be bored would be to have it sonic checked but I would be doubtful that it could be. I have a '65 or '66 (don't remember which off the top of my head?) 421 block that is currently .060 over and it will go .090 but will be at the margins and one hole will need to be moved .015 to the rear to do it. And that will be the last boring of that block. I had it sonic checked.

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Old 07-30-2020, 06:46 PM
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I just had a 69 4 bolt 428 block sonic checked. It is already .070 over, it needs a sleeve and I will take it to .090. On the major thrust side it ranged from .210 to .220 on the minor it ranged from .185 to .195. I have taken a few of these to a 4.210 bore. Sonic check will know for sure. I think Probird had one a 4.250.

This block was a GME casting.

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Old 07-30-2020, 08:09 PM
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I have a 400 bored .090 over and put in a 4" crank and made it a 441. Don't remember what was left on the thrust side when it was sonic checked but it was enough.

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Old 07-30-2020, 10:17 PM
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Looking at it next week. Keeping my fingers crossed on the RA4 heads. He’s a money guy from years back. Anything’s possible.

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  #6  
Old 07-31-2020, 05:48 AM
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If they are RA4 heads there certainly worth a bunch more then the bare block assuming there usable also!

  #7  
Old 07-31-2020, 12:19 PM
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Quote:
Originally Posted by Hooter View Post
Looking at it next week. Keeping my fingers crossed on the RA4 heads. He’s a money guy from years back. Anything’s possible.
I have a '69 428 block in my race car that is .130' over. It's hard blocked have way up the water pump holes though. When I sonic checked it before boring it averaged .290 to .310 un the thrust side.

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Old 07-31-2020, 01:55 PM
Dragncar Dragncar is offline
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Quote:
Originally Posted by Tim Corcoran View Post
I have a 400 bored .090 over and put in a 4" crank and made it a 441. Don't remember what was left on the thrust side when it was sonic checked but it was enough.
How does that thing run ? What kind of heads are on it ? I have a 67 .060 400 block been thinking about doing that.

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Old 07-31-2020, 02:13 PM
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Yes it runs just fine until I had an exhaust valve sticking now I have it apart to fix it. I has 6X heads ported out to 265 @28" of water and 9.0:1 compression. It has a pretty small cam in it and it has ps,pb,ac a Q-jet factory intake and runs a disappointing low 13's in the 1/4. I will be putting in a different cam while I have the engine out and we'll see if it improves. I expect with those heads it should easily be in the 12's. The pistons are an off the shelf SRP flat top i believe they are chevy 400 pistons.

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Last edited by Tim Corcoran; 07-31-2020 at 02:24 PM.
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Old 08-03-2020, 10:10 PM
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A little update - got to see the car today. The motor is in a 81 TA that hadn’t seen the light of day since 2000. The car cover had rotted off it and covered in dust from the storage unit it’s in. Sadly, no ram air 4 heads, but it does have 670’s. Motor turns over. Pulled a valve cover breather and has gold colored roller rockers. Torker 2. 800 Holley. Lots of good stuff. Agreed to buy for $500. Not sure what I’ll do with it, but couldn’t pass it up. Be a nice motor with some 6x heads in my Bonerville.

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65 Lemans Street Car - 521, T400, 3.70 9". 10.13 @ 135. 3770 lbs

63 Lemans Race Car- 8.81 @ 151, 5.60 @ 123(SOLD)

67 Bonneville ragtop

74 Firebird - 455, e heads, TK0600 in process
  #11  
Old 08-04-2020, 02:21 AM
1965gp 1965gp is offline
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Sounds like a great score

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Old 08-04-2020, 12:42 PM
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Wow that’s just about giving it away great score for you.

  #13  
Old 08-04-2020, 06:29 PM
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77 TRASHCAN 77 TRASHCAN is offline
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Hooter,
Saw your name recently on the birthday announcements, belated Happy Birthday!!!
Was going to post in Lobby, to see whet you were up to...now we all know!!!
I hope ALL the parts are usable!!!

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Old 08-04-2020, 08:15 PM
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Quote:
Originally Posted by 77 TRASHCAN View Post
Hooter,
Saw your name recently on the birthday announcements, belated Happy Birthday!!!
Was going to post in Lobby, to see whet you were up to...now we all know!!!
I hope ALL the parts are usable!!!
Thanks man. Only 1 year away from ordering off of the back of the Denny's menu(55 and over) lol.

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65 Lemans Street Car - 521, T400, 3.70 9". 10.13 @ 135. 3770 lbs

63 Lemans Race Car- 8.81 @ 151, 5.60 @ 123(SOLD)

67 Bonneville ragtop

74 Firebird - 455, e heads, TK0600 in process
  #15  
Old 08-06-2020, 08:25 AM
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Quote:
Originally Posted by Hooter View Post
Thanks man. Only 1 year away from ordering off of the back of the Denny's menu(55 and over) lol.
LOL, I'm a little older (61).Keep getting AARP membership applications in the mail every year. I think it costs $35.00 yearly. There isn't a darn thing (or things) that I'm going to be spending money on, to save $35.00 on. They don't know me very well.....
Looking forward to seeing tera down of 428!!!

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  #16  
Old 08-06-2020, 11:43 AM
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Happy B-day kid...I mean "HOOT".
If not gon'a use those 670's. Be interested in date code. The F017's on my 67 need completely gone thru. Guides, seats, valves and springs shot.

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