I know they are 87 head's an some were around 285 300 hp but can some one tell me what is the max lift the springs can take.14101083 any idea of horses 355 flat tops head's planed .20 three angle valve job roller rocker performer intake cam not sure maybe comp 270 short header's 2 1/2 pipes thx's just a bird ......

Any idea's

i will venture a guess, mind you a guess.

probably in the .450 to .500 gross lift area. this is the normal safe zone for late 80's and 90's OEM stuff, it is on the conservative side too i bet. i do not like to push the tolerances much, too easy to break stuff that way.

if you re-cam a motor it is a good idea to put in the valve spring's the cam maker recomend's unless you have new head's and the gross lift is in the spec area of the springs.

are they head's used? if so i would at least get them check out and go from there. at the least you should get them tanked and have a valve job done on them. and new hardware and springs too.

valve springs take alot of punishment and new springs&hardware are cheep insurance IMHO.

[This message has been edited by ilbl8 (edited 02-02-2001).]

[This message has been edited by ilbl8 (edited 02-02-2001).]

Thanks the head's have three angle job done feel kinda dum what dose that mean?they have been shaved .20 i have roller rockers i guess theses heads needed something like the vortec's for rockers.I got the engine thinking they were vortec head's duh! but i'm told they are 285 to 300 hp heads should they work alright with 355 flat tops an performer intake thinking of a double feed carb but i have a 625 holly single should they work alright?

Thanks the head's have three angle job done feel kinda dum what dose that mean?they have been shaved .20 i have roller rockers i guess theses heads needed something like the vortec's for rockers.I got the engine thinking they were vortec head's duh! but i'm told they are 285 to 300 hp heads should they work alright with 355 flat tops an performer intake thinking of a double feed carb but i have a 625 holly single should they work alright?Thx's just a bird

A three angle valve job refers to the number of different angles cut into the valve seat. A 3 angle valve job will normally add a few hp over a standard 2 angle valve job. Your combo sounds very good...that cam is perfectly streetable with a nice healthy idle, and with .470 lift clearances wont be a problem. I would definately use matching comp cams springs, retainers, and locks though...even though the stockers will work they really dont have enough pressure (especially if they are used) for solid valve control at higher speeds...one good valve float and you could be building another engine. Your best bet is to purchase the k-kit...it has the cam, lifters, locks, springs, retainers, seals, double roller timing chain, and lube...and the price is very reasonable (cheaper than buying the stuff seperately). Flat top pistons with these heads (64cc) will give you anywhere from about 9.2-1 compression and up...depending on deck height and head gasket compressed thickness.

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375hp 78 Chevy truck
77 Chevy Nova
95 Chevy Lumina 3.4L
and building a 78 Nova

thx's just a bird