[performerrpm]

so...I dont think theres a huge market for 406's with all the stroker stuff available. had my rotating assy listed awhile, in fact so long that i done got another 400 block back from machining. learned my lesson on my 455, i will be assembling 4 pistons and measuring deck height, not planning to 0 deck but try to put the pistons.005-.007 in the hole that way i can reach the ideal quench with a felpro vs cometic gasket.
the most streetable situation is that i run the bastard child dport 72cc eheads, hr voodoo 713 cam with rpm intake although it could also have a 66 tripower on it if it finds its way to my 66. not the most street friendly set up.

other options, racier set up
same set up but 290b6 cam, same bastard heads lol, probably a no on the tripower but possibly the rpm.

2nd option, i have some 64cc round ports, supposedly done up by sdperf...325ish cfm but no flow sheets to prove it. 660 solid roller springs and a matched 4150 victor. i considered using the 713 cam with a set of solid rollers. i didnt buy these heads for this shortblock, but if it could make a stout 400 id use it. the rpm is untouched, but i could probably make an attempt at cleaning it up to use with the heads if the vicor is just too much intake for the cubes

the pistons are ross 8cc flatops, eagle h beams and a stock crank balanced. i gapped the rings for this for a 150 shot just incase.

[steve25]

Your posting in the race section so for me I will assume that 80 percent of the time this motor will be running it will be for that usage.

That all being said and looking at the differences in compression you will have between these builds what octane level are you willing to fund for fuel cost?

With 406 CiD I would build with the 64 Cc heads .

I also need to ask what track times are you looking to achieve?

[performerrpm]

Steve, if i didnt use the tripwer/ hr cam in this for my 66 then it would find its way into my 65 gto backhalve car. i already have a couple motors for that car but this would be set back for just incase. the car itself will be set up to run e85 with mpfi. for this set up i would use a sniper 4500 if at all possible adapted to this 4150 intake, or swap to a 4500 intake that would need matched to the heads since its untouched.

hours an hours of googling the pontiac sites and really ive only been able to find one thread by screaming chief about the 290b in a 400, seams like thats about as big as you woukd want to ago in a 406 but i dunno if the extra compression and headflow would open it up to bigger or not

[performerrpm]

its a 4 speed car with 4.29 gears and 31x18.5x15 tires....if it someday gets mid nines id be stoked...lol also be getting outran by hellcats and mustangs but owell

[Dragncar]

Originally Posted by performerrpm

its a 4 speed car with 4.29 gears and 31x18.5x15 tires....if it someday gets mid nines id be stoked...lol also be getting outran by hellcats and mustangs but owell

That, is a tall, tall order.
Are we talking a real 4 speed ?

[performerrpm]

Originally Posted by Dragncar

That, is a tall, tall order.
Are we talking a real 4 speed ?

its a jerico 4 speed

[Dragncar]

Originally Posted by performerrpm

its a jerico 4 speed

Nice.

[performerrpm]

i maybe able to squeeze a few more ponys out of this afterall...if the pistons get situated.

im gonna throw on a paxton 1200sl in the mix.

i have the vortech equiv on a ls1 that gets with it, hoping the same result on a pontiac....later ill change it to the bigger 2200 but i think the 1200 is capeable of pushing this shortblock to its limits with the parts being used

[MatthewKlein]

Originally Posted by performerrpm

bastard child dport 72cc eheads.

What are bastard edelbrock 72cc heads?

[performerrpm]

Originally Posted by MatthewKlein

What are bastard edelbrock 72cc heads?

lol...i had bought a set of 72cc hr edelbrock d ports, all my headers were for round ports. since i already had some round port eheads to use also, i tried to sell the dports here and market place...the heads were, are stillnew. went 500 lower and offered an rpm intake. nothing...until one day a guy messaged said 2500 right now...ok sounds good...ask me a gazillion questions...finally asked to call...ok. he tells me" ive got a nice set of iron heads i can use, i really dont need the aluminum heads" then he says i tell you what...2400 shipped...from oklahoma to new york! i told him it sounds like your iron heads are just what you need, go ahead and keep those and ill keep these..gluck with your build....hung up the phone and promply deleted all fb ads for the heads. even my bro backed out on buying them....now ive got an amazing set of 2" huslers to work with them so i figure ill usem

[performerrpm]

i got sidetracked from this one....but i did end up taking it back to get 0 decked. weird, one side was .020 in the hole front to back, other side was .020 and .015 at the back. so i ended with one side 0 decked, tbe other .0-.005 . line honed with arp studs. still keeping the same 406 assy. file fit rings, gapped for 150hp or 10psi. the difference in gap isnt much on a 4.15 bore really. i tapped all the lifter bores for restrictors just incase but im leaning torward the hr 713 just because i might try to sell this one later...only for the fact i dont have as many pontiacs as i do motors.

even though it was hot tanked and jetted. the galley plug in back was not coming out...one by dizzy wasnt either...so once i deburred the block, i drilled all those out and spent a quit a bit of time flushing out the galleys with miniral spirts and brushes. just now got a open spot in garage to paint...hopefully itll go together over the next week or so.

[performerrpm]

got most of the shortblock together, minus 1 broken file fit ring. the bevel at top of cylinder after decking wasnt filed back in as good as the others along with my 20 dollar compressor.

checked end play...was barely getting .0015 but hadnt set the bearing yet. couple decent smacks on end of crank each direction with a 2x4 and hammer i ended up with ' after several checks and re checks .0065 to .007. that was with caps slightly backed off. hopefully when i check again once the last rods torqued it will stay the same.

[steve25]

Even with those extra size exh valve notches in those pistons be sure to check the ring side clearance if you have gone up to a 1.77” exh valve.

Edelbrock moves the exh valve over ,040” closer to the bore so as to move over the intake so it’s more unshrouded and can allow the use of a 2.19” intake valve.

[PAUL K]

Looks good!

[performerrpm]

Originally Posted by steve25

Even with those extra size exh valve notches in those pistons be sure to check the ring side clearance if you have gone up to a 1.77” exh valve.

Edelbrock moves the exh valve over ,040” closer to the bore so as to move over the intake so it’s more unshrouded and can allow the use of a 2.19” intake valve.

these heads just have the 1.66 valves that comes with them from edelbrock. since its 0 decked i figured i shoukd check anyways. the 2 cam choices arent super crazy in lift with 1.5 rockers

[Skip Fix]

Here is the picture of the clay on the 400 I am freshening with Paul K cleaned up round port E heads and a 242/249@ 0.050 .3707 lobe UD SR and a HS 1.65(that measures 1.7) and zero lash. One hole is 0.008 out.
Not sure where the little dents in the piston cam from!
65 GTO needs a decent motor to at least pull it around the shops and maybe some Roadkill driving!

[performerrpm]

Originally Posted by Skip Fix

Here is the picture of the clay on the 400 I am freshening with Paul K cleaned up round port E heads and a 242/249@ 0.050 .3707 lobe UD SR and a HS 1.65(that measures 1.7) and zero lash. One hole is 0.008 out.
Not sure where the little dents in the piston cam from!
65 GTO needs a decent motor to at least pull it around the shops and maybe some Roadkill driving!

im part tempred to drop this one in my 65 just to fire it up. i even looked at my sons 64 sitting off to the side and eye balled it as a potential run stand

[performerrpm]

got my ring situation took care of ' broke one'. i gapped these @ .0055x4.15 bore. that was the gap for upto 150hp n20 or 15# of boost. my goal was .0023 top and bottom. the tops i did ok i think .0023 to .0024. the bottom ring i kept the same but i wont say that on one i couldnt get .0025 gauge in and one other closer to .0026 than .0025. overall i still think this is closer than i would have got with drop in rings.

the shortblock is done aside from waiting on the oil pump ds. i also added the .060 washer to the pump but left the 5/8 ball. im glad i took it apart since there was a bit of shavings under the ball from where the threads were tapped. i cleaned it all out an took a small file to edge of gears but thats as much as i did in that area.

lastly the cams in...id love to sell this motor later so the hr cam probably would have been the way to go. theres a better chance than not that i will be stuck with this motor unless i sell at a loss ' pontiac parts just seems to be in the dumps'. i been wanting to run a 290b for years and this is probably the best option i have for that so i got it in. soon as the keys get here ill degree it. it seems this cam works great for everyone installed at 106icl. it also looks like even on bigger cube motors installing advanced 3° is works even better. i thought maybe in this smaller motor 3° maybe best case for this combo..

heads n rpm intake will be untouched for now. if it becomes permanant fixture in the garage ill swap out the rpm for the 66 tri power just for nostalgics sake

[TXSTARFIRE]

Those dents look like a roller from a needle bearing, not sure how that would get in a motor.

[Skip Fix]

Head chamber did not have any dents to match the piston so a mystery for sure. That motor did have a bunch of intake swaps, cam swaps but was always a HFT. Norris rockers 1.6 all still good too.