The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 01-02-2012, 04:35 PM   #1
davepl
Registered User
 
davepl's Avatar
 
Join Date: Aug 2006
Location: Redmond, WA
Posts: 6,332
My 402 heads are listed for "366/427"

The casting numbers on the cylinder heads for my 70 GMC 402 are 3975950, which at every source I've checked shows them as

1968-70 366/427 2.06/1.72 Closed Chamber

The block is TO42TTBG, which is 402. Now I'm a little confused, because the 366/427 are tall-deck engines and the intake manifold wouldn't fit, even if you could mix and match tall deck heads with a short deck block.

Are the sites I've checked all wrong, or do I have the wrong heads on this truck?

Thanks!
Dave
__________________
1970 GMC Sierra Grande Custom Camper - Built, not Bought
1969 Pontiac 2+2 427/390 4-speed Coupe
1969 Pontiac 2+2 427/390 4-speed Convertible
davepl is offline   Reply With Quote
Old 01-02-2012, 06:56 PM   #2
425HP409
425hp409
 
425HP409's Avatar
 
Join Date: Oct 2008
Location: Prosper Texas
Posts: 841
Re: My 402 heads are listed for "366/427"

The heads will interchange between tall and short block. The .400" taller block puts the heads wider apart and that is why you must have a 366/427 tall block intake.
__________________
Charles
68 SWB, Dad bought new, now 396 & factory ac
64 Impala SS, 409 425HP, 4 speed AC
64 Bel Air Wagon, 400 Small Block
57 Bel Air all original 283 w/Factory Air
77 GMC Sprint, 454/425HP
67 Olds 442, all original
90 ZR1 Corvette
425HP409 is offline   Reply With Quote
Old 01-02-2012, 06:59 PM   #3
davepl
Registered User
 
davepl's Avatar
 
Join Date: Aug 2006
Location: Redmond, WA
Posts: 6,332
Re: My 402 heads are listed for "366/427"

Thanks! And from searching, it appears these heads are not uncommon on the 396/402, just bad reference material I was looking at I guess.
davepl is offline   Reply With Quote
Old 01-03-2012, 08:21 AM   #4
special-K
Special Order

 
special-K's Avatar
 
Join Date: Nov 2004
Location: Mt Airy, MD
Posts: 85,851
Re: My 402 heads are listed for "366/427"

They could have been replaced.
__________________
"BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed"

GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project)
GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling)
Tim

"Don't call me a redneck. I'm a rough cut country gentleman"

R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~
special-K is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 02:18 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com