i bought a long block it is an 71" but i could not find the cast# in a book the # is 481990 the last # was hard to read i think it is a "0". it has 4X heads on it but front and back bolt holes for the exaust are not drilled on both heads was there a reason for this? Thanks for any help!

i bought a long block it is an 71" but i could not find the cast# in a book the # is 481990 the last # was hard to read i think it is a "0". it has 4X heads on it but front and back bolt holes for the exaust are not drilled on both heads was there a reason for this? Thanks for any help!

481990 is the block casting code for a 1971 350.

Was there a reason for the end holes not being there? Not really. Probably so the factory could save 2 cents.

johnta1
Pontiac Power RULES !!!
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thank you. i was thinking about getting headers and was sure if i would have drill and tap the bolt holes?

If it's got the flange there,just not drilled,go ahead and drill and tap it.

If it's missing the flange altogether,look up Paul Spotts at Spottsperformance.com

johnta1
Pontiac Power RULES !!!
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thank you! i curently have a points ingition and want to change it to hei or pertronics magnetic pick up conversion kit do u know anything about these kit? or is hei better? i will have to check the heads for the flang, but i'm pretty sure there. thank u again.

Personally I would go with the HEI.
The Pertronix seems to be ok,except they make 2 versions.The one with the lobes is better I think.

johnta1
Pontiac Power RULES !!!
www.wallaceracing.com
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thanks i went with the HEI and the engine runs a smoother and has more power.

thanks i went with the HEI and the engine runs a smoother and has more power. http://forums.performanceyears.com/g.../icon_wink.gif