1976 455 upgrades
#1
1976 455 upgrades
im going to start this thread on the upgrading process of my 1976 cutlass supreme 455 ,ill be working on it this winter .as it stands now everything is bone stock and im looking to wake it up .dropped my 1970 e heads off at the machine shop and got
quoted between 8 and 9 hundred to redo them. includes new valves, guides,seals ,springs and machine work .were going with the 2.072 and1.625 valves they currently have the 2.000 valves.id liked to use my original rockers , retainers and push rods .which brings me to my first question how much can we mill off the heads and still use my original push rods?
quoted between 8 and 9 hundred to redo them. includes new valves, guides,seals ,springs and machine work .were going with the 2.072 and1.625 valves they currently have the 2.000 valves.id liked to use my original rockers , retainers and push rods .which brings me to my first question how much can we mill off the heads and still use my original push rods?
#3
Got the eheads back from the machine shop . Installed stainless steel valves 2.075 on the intake 1.710 on the exhaust new guides and dual valve springs from comp cams 125lb on the seat and 245lb open . New retainers,locks and seals milled .008 off the heads to get them smooth and took a little off the exhaust as well . Cost came in at $1000 a bit over the estimate. Time to make a decision on the cam .
#5
I may end up buying the push rods as well .have no idea about how to verify correct lifter preload I'll leave that up to my engine builder buddy in the process of ordering a e Brock 2151 intake and a 800 cfm ebrock carb .
#7
Yes low compression but machine shop guy said he went a little bigger on the exhaust due to the condition of the heads around the ports . Does that make sense and do you see any issues with that?
#8
X2 plus it will hurt gas mileage, not like that's a concern with a 455. If you are starting from "bone stock" get a 73-74 double hump transmission cross member so you can put a proper dual exhaust on the car. It will make a huge difference.
#9
Yes been searching for double hump for a while now .do have a quadrajet from a 1973 350 rocket I could rebuild .or use the existing stock quadrajet that's on it.ill hold off on carb selection for now
#10
He should've just put seats in it.
I made 415hp and 540tq on a 442 W30 build. It had the original intake, carb and H heads on it with 1.62 exhausts. That's one reason why it made so much tq.
I'd do a single pattern cam even more so now.
#11
He did say they had to pound the valves out because they were rusted in I'll take your suggestion on a cam I doubt this motor would ever make 400 horse with these pistons but we'll see I might end up with a three thousand dollar boat anchor
#14
Electric. Just remove the three screws holding the thermostatic coil on, remove the gasket, attach the electric choke coil, and connect it to an igniton switched 12 Volt source. I put a tubing cap on the threaded hot air nipple just to keep dirt out.
I bought the one on my car from a salvage yard for $5.
I bought the one on my car from a salvage yard for $5.
#19
I had a 1970 Cutlass S that I put a 455 in and I had 2.56 gears. The suspension was questionable at best so really high speed runs were out of the question, but that thing would scoot with no issues for sure. I also was able to coax a 13.89@97 out of it with those gears in it.
#20
That's easy to do with what you have. All you need is a cam and headers. I love running the low compression 455's. I ran one in my daily driver with headers, an Edelbrock Performer RPM cam, stock G heads, stock intake and Quadrajet, stock trans and converter, 3.23 gears, 3900+ lbs., and ran a best of 12.84 @ 100 mph with open headers. Had the same combination in my racecar, except E heads, 3.90 gear, and 3550 lbs., and ran a best of 12.18 @ 109. One more thing that the low compression likes is a lot of timing. I run around 20-22 initial and 45 total. They love it.
#21
X2 on a lot of timing. Run at least 38 total for timing. For part throttle, as much as it can take, usually around 60 degrees. It will help mileage and feel crisper at all throttle openings. The stock cam isn't terrible on the 455, basically the 307 HO or 350 manual trans cam. Talk to Mark about the cam. The Electric choke coil is a replacement for a Chevy Qjet from the late 70's and on. I use a dab of JB weld inside the housing to block the vacuum port.
Last edited by olds 307 and 403; October 19th, 2016 at 06:39 AM.
#23
Yeah, but doing that you're kinda screwed if you (or another person) want to go back to the hot air choke with that carb. A tubing cap on the port makes it easy to swap back, plus it keeps critters out of the choke housing.
#25
Found a nice duel hump crossmember for the car got it sanded primed and painted will put that in soon. pm sent to mark on cam and lifters .looking at headers now as well .
#26
Jeff,
I went with Thorton MFG on HO cast exhaust manifolds. They acquired the specs and dies and reproduce the higher flowing dual exhaust manifolds from the w30s.
I had hedman headers on my 350 prior to the swap to the 455. I didn't care for them, hung too low, until you got headers tightened up after multiple heat cycle they would stop leaking, that was also using a copper crush style exhaust gasket as well.
I also recommend going with the quadrajet. I live in the midwest and prefer the hot air choke, more responsive for me in killing the choke than the electric. I did the electrico on the olds 350 with edlebrock Performer RPM intake and 650 Ebrock carb. Still have it on the motor, on the stand should I find something to put it in..
I went with Thorton MFG on HO cast exhaust manifolds. They acquired the specs and dies and reproduce the higher flowing dual exhaust manifolds from the w30s.
I had hedman headers on my 350 prior to the swap to the 455. I didn't care for them, hung too low, until you got headers tightened up after multiple heat cycle they would stop leaking, that was also using a copper crush style exhaust gasket as well.
I also recommend going with the quadrajet. I live in the midwest and prefer the hot air choke, more responsive for me in killing the choke than the electric. I did the electrico on the olds 350 with edlebrock Performer RPM intake and 650 Ebrock carb. Still have it on the motor, on the stand should I find something to put it in..
#28
#30
worked on removing the single hump crossmember last night and taking out the exhaust system.can you believe this great big 455 breathing out a single 1-7/8 tailpipe !trying to keep everything in tack in case someone needs a complete system .even has the old test pipe in place of the cat on it .
#32
finally getting around to taking the motor apart. spent 3 hours taking off the exhaust manifolds.(amazing how tough those bolts are)everything is coming off pretty well .ended up buying the w/z manifolds from fusick olds and a edelbrock intake .engine looked great inside 'the original owner must have done regular maintenance .
#33
Cue the snowball effect !! After looking at some of the brittle gaskets as I take this motor apart I decided to pull it out and replace the rear main seal and oil pan gasket . I'll have the opportunity to clean , paint and regasket .may have to wait for a little nicer weather .the time I spent taking things apart the hard way I could have had it out on a stand .it appears to have had the timing chain and gears replaced, not sure if these 76 455's had those gears covered with that plastic like material that use to shatter all to hell.already have a cloyes double roller for it .
#36
update ! so the motor is out (big red engine hoist from tractor supply doesnt have a long enough boom for this long nosed cutlass but we got around it .my son and i got it on a stand and removed the heads pushrods and lifters spent a couple hours wire brushing and gasket scraping .finally got the block painted by ten oclock last night .expecting my brother in law today so we can install a new rear main seal, cam,lifters and new intake manifold .
#37
got most of the work done yesterday will bolt on the exhaustt manifolds today and need to get some plugs for the intake .this edelbrock 2151 came with cast iron blanks to block off the crossovers ,took some grinding but they fit nicely .
#40
update ! so the motor is out (big red engine hoist from tractor supply doesnt have a long enough boom for this long nosed cutlass but we got around it .my son and i got it on a stand and removed the heads pushrods and lifters spent a couple hours wire brushing and gasket scraping .finally got the block painted by ten oclock last night .expecting my brother in law today so we can install a new rear main seal, cam,lifters and new intake manifold .