Originally Posted by Jdmoell
New to the site with stupid questions...I have a 1966 pontiac bonneville that I have owned now for 26 years. Can finally afford to do a few mods...the engine is bone stock 400...no idea on heads or year 72-76 from some donor pontiac in Alaska.
will be a daily driver and family car and very basic horsing around in...
I am wondering if this hair-brained scheme of mine is sound:
Looking to add kit from e-bay:
K KIT INCLUDES:
51-600-9 THUMPER CAMSHAFT
857-16 HYDRAULIC ROLLER LIFTERS
2112 TIMING CHAIN SET
995-16 Valve Springs
611-16 Valve Locks
503-16 Valve Seals
7775-16 Hi Tech Pushrods
the specs on the cam are:
Valve Setting in/ex hyd
adv: in 283
@.050": in 227
Valve Lift @ 1.5:1
Also looking to add:
Dual quad set up, idle to 5500rpms, dual 600cfm manual choke carbs with universal linkage.
Just wondering if this is reasonable to do...not looking to do any major machine work. This engine has 5000 miles on it and runs smooth on 89 octane...sluggish yes but smooth. Please advise. Thank you
Cam is not what you want. Period. The LSA is too close together making the power band at a low RPM and very narrow. Also regardless if you have the compression to run it or not, the duration is too large for tall gears +auto matic without a higher stall converter.
That cam will be a real dog off the line and wont idle correctly unless you put in a higher stall speed converter.It will run out of power quickly due to the short LSA.Plus the tall gears will limit how well it launches.
72-76 pontiac 400 s had large chambered heads (due to manufacturers attemps to meet EPA specs) so your build strategy may change /evolve somewhat here.Its a good thing.
What heads are on the motor as of now? are you going to run those heads?
If you want to get the most bang for your buck, have a fun car with good power, stroke it to 462 with a kit from butler.Use KRE D prt heads with the 85 CC chambers.The dual quad setup will run well with them, also with the block zero decked and the KRE heads, you will have a good quench, so pump gas is feasible.
You will need a 2000 rpm stall converter and a gear change from the 2.56 you prolly have, to a 3.08-3.23 would be better.3.55 would be Ideal.
Naturally the butler kit has forged rods and ross forged pistons.Very much needed where you are going with this build.
NOW.... the problem is , building that sort of power takes time and money to do right. You wont be driving it in a few weeks. If your serious about the build, I would recommend finding another bare block and start from there , leaving the engine in the car intact and runable for the time being, so you can still drive it. Then when you elephant engine is done, just swap it out over the weekend.
Having a car torn apart for a long period of time tends to be an oppresive matter....parts getting lost, no driving it...bummer....loss of interest. Dont go there. Build a motor to swap.If the new engine ever goes bad (hope not) you can put the other one back in and still drive.
There are stiull plenty of 400 blocks around to be had.If your building a stroker , like the 462 CI stay away from the 557 casting as they are weaker in the main bearing web area. That is an important area for strength as you are increasing the forces that act on it by increasing the stroke and the energy produced.
Give it some thought, and post back. There are some WAY cheaper alternatives to getting more HP and torque without a ton of cash and parts involved.
Oh and buy the way, the cam you posted wont make enough vacuum to run the power brakes, so a hydra boost may be in your future as well.