tanager11

I need some help with somethign. Here is the background. Have a car with 187 Heads on it (for use with Self aligning Rockers).....and I am in the process of putting a set of 416 heads onto it (from what I have read all 416's are for use with non-self aligning).

I keep reading that in order to use my Self Aligning Rockers (which I want to do)...I have to drill out the holes for the push rods larger. BUT...when i look at the push rod holes in the 187 heads vs. the 416's they look IDENTICAL. Am I missing something here...if they look the same do you guys think I am safe tossing the SA Setup I currently have onto the 416's and using that because everything looks the same with respect to the push rod holes or is there something I am not "seeing"

HELP!!!!

Dave

ME Leigh

I don't think the 187 heads use self-aligning rockers. IIRC self-aligning rockers didn't come till the vortec heads 906, 062.

tanager11

if thats the case that would be PERFECT....but I think that might be incorrect....all the TBI guys are saying that thsoe swirlport heads (187) were self aligning.

xpndbl3

iTrader: (5)

nm

F-BIRD'88

Pick one method of guideing the pushrod.
Either ...or but not both.Either use standard pre 87 non self guiding rockers on your 416 heads or drill out the pushrod guide slots in the heads and use 87+ self guideing type rockers.

ShiftyCapone

iTrader: (7)

TBI heads are SA.

Stekman

I believe the switch from non-SA to SA came around when the perimeter bolt to centerbolt switch came around. I believe that would also be the time that the center bolts of the intake were switched to the 72° pattern, rather than the normal 90°, so that might be another thing to watch out for.

But F--BIRD is correct, you only need 1 method of pushrod guidance. IMO, the most preferable is the guideplate/screw in stud combo.

badone07

Some 187's and 193's are non-SA. I've seen both (SA & non-SA) but they were mainly in the earlier production (87-88 TBI vehicles) of the center bolt valve cover heads.

Stekman

Correct, some 87 heads got the non-SA rockers, however, since most got them i guess i just consider TBI heads as SA...

tanager11

Hmmmm....given the above comments that some came with SA and some N-SA Rockers....is there a way to visually check the rockers themselves to see what they are??

I can see directly from the push rod holes in the old 187 heads that they are the smaller thinner ones.....maybe this is what is causing me all this confusion.

Either/or I am finishing this thing off tonight.

Thanks for all yoru help guys.

Dave

ME Leigh

Yes SA rockers have a little lip on each side on the rocker. The valve tip fits in between and aligns the rocker, hence the name.

five7kid

iTrader: (14)

I picked up a complete '87 LB9 that had been rebuilt (didn't know that at the time). It had one TPI head (081) and one swirlport (187) head. Both centerbolt cover, BTW. Neither head had the large SA pushrod holes.

Since the pushrod hole isn't part of the casting, casting # doesn't really tell you what you've got (in this case). So, watch what you've got - the factory did some really weird and unexplained things (even inexcusable, I suppose you could say).