The 1947 - Present Chevrolet & GMC Truck Message Board Network

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)
-   Engine & Drivetrain (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=24)
-   -   487X cylinder heads. . . (https://67-72chevytrucks.com/vboard/showthread.php?t=66055)

racedvl 08-25-2003 12:02 PM

487X cylinder heads. . .
 
Are 487X heads any good? I have a set, I'm I'm thinking that I would rather have a set of non-906 casting Vortec heads. Does anyone have any input on this for me?

lukecp 08-25-2003 01:16 PM

487X heads are a fairly rare find....they came on early '70's LT1 350 engines.....being a "X" casting, the intake ports are 10cc bigger than the standard 487 heads. They might already have 2.02/1.60 valves too. The combustion chambers are 75cc's though, so if you want high compression you would have to run a domed piston.

If they are in good shape, i would use them, especially if they have 2.02/1.60 valves. Pretty much, they are a open-chamber performance head. Vortecs will flow better.....and make more power though.

bpmcgee 08-25-2003 03:11 PM

Race,

Regarding your comment on the 906 Vortechs -- Chevy High Performance actually retracted their first comment about 906s not flowing as well as 062s. They now say that both castings are about the same.

Just FYI,

Brian

67_SS396 08-25-2003 07:50 PM

487's are a good head and the 487x's are better, also very rare and "should" have 2.02/1.60 valves. They are a pretty thick casting and only have a single crossover, so they are not as likely to crack like the 882's and such. With a little bit of work, they will flow nicely for a driver/cruiser.

bigjimzlll 08-25-2003 08:31 PM

My advice...Sell them to someone who needs them for class racing or a numbers matching restore. What hurts is the 75cc chambers and the soft valve seats. They are nice heads though..for real old school

nate68 08-26-2003 12:19 AM

i used to have a set of 487x's. the x really means that they have hardened seats. the intake ports are the same size. they made them from 71-73 on vette lt1's. 1970 lt1 heads were closed chambers. my 487x's had 1.94 valves.

ChopTop 08-26-2003 03:18 AM

Nate I recently traded a set of 487X heads due to the fact every single excaust port needed hardened seats installed. Not to mention guides all-around. I was lucky the machinest had a set of 487's laying around that did'nt need as much work.

milner 08-27-2003 10:15 AM

Question about the 487X heads. I bought my 72 custom deluxe with a bad motor(I was told it had a rod out). I put a motor I had lying around in with vortecs on it. Anyway,I came across a deal on a 383 that I couldn't pass up. It is a shortblock only,I want to put it in my 79 K10. It has a THIRSTY 400 that is worn out,also has fulltime which doesn't help matters. I checked the heads on the motor last night and they are 487Xs,I was thinkin about using them on the 383. It is not a race motor,I was thinkin about vortecs again but with 64cc heads the c/r would be 10.3-1,alittle to high. What do you guys think?

nate68 08-28-2003 12:34 AM

the 487x's that i had, had hardened seats. i think they were 1972 casting date

73stepside 08-29-2003 02:50 AM

10 on the cr is high but with vortecs you can retard the timing and probably not get any detonation and be happy with the power output. i've heard that vortec'd motors do not reqiure nearly the amount of initial advance than non-vortec'd motors.


All times are GMT -4. The time now is 12:23 AM.

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