My 70 GS455 had a persistent front cover leak and some performance issues, so off it went to Ivyland collision for some TLC. After speaking with Nick Serwo and going over some options, out goes the 455 for a much needed refresh. I had a fresh pair of Gessler stage 1 iron heads and ported intake waiting in the wings. Nick is taking care of the bottom end as we speak. Looking for some much needed reliable and upgraded power, let's see what the new combo will bring!
So, it's going to be a ported 70 S1 iron head motor. Any guesses on where this will land on the dyno spectrum? A couple more build pics....
Mild cam with manifolds 440 Aggressive cam with manifolds 460 Both on pump 93 headers would add 20ish
Looking good! Ahh man this is making me want to get back going on my 70 455 build. Unfortunately I had to put it on pause to rebuild my TH400 so I could enjoy the car this season and that ate up my engine fund so back to saving I go.
I told Lee I would post the specs Bore 4.350 Deck 10.563 Gasket felpro Performance .041 4.380 dia 23 cc Wiseco pistons on Molnar rods Cast rings Compression is 9.63 Heads are 68 CC 1070 455 block Drilled oil passages , all hard truns radiused for flow & stepped front galley oil plugs Ta cover with new gears deburred & wear plate port matched for flow v6 filter housing set end clearance on pump. Rollmaster timing chain cam degreed set +8 adv arp bolts Groved cam bearings Modified pick up tube with AMP screen Oil pan is a 6 quart replacement with AMP Baffle welded in rear Heads are Gregs Gesslers level 3 Int .600 274cfm / Exh .600 200cfm 2.130 Intake 1.75 Exh /120 seat on springs /280 open Cam is Comp 230/240 .506/.525 on 112 cl installed @ 108 Lifters are delfi GM Manley pushrods custom length Stamped Steel 1970 rockers Intake is stock 1970 style ported By Greg & divider cut Main Bearings clearance set @ #1&2 .0028 /00025/ .003/ #3&4 /.003 #5 Molnar Rod bearings .0023-.0025 1970 Qjet 704040 & 1971 800 to test A set of ported 1970 Manifolds
Had to go +8 to get to 108, I had to due the same thing with my 308s. Though I had something wrong, clearly there are other combos that need the same