The 4x heads arrived !!!

frosty can you tell me what year they are ? I see casting dates of A094 and A114 

and there is a 7h code on them too ? i am so not sure what that means ? i want to know what cc they are , could be 98cc or 114cc so i recon i will have a go at ccing them myself !

 

What is interesting is they have screw rocket studs , tapered spark plug holes ! Not flat ones and the heads look to be painted factory grey colour ! Not Pontiac blue !!! What’s with that ? 

 

Edited April 19, 20251 yr by 64 kiwi boni

When I researched strokers, all will bolt in without relieving the block except for the Big Daddy 472.

I am thinking 4.5 stroke but I want two lanes thoughts before I go any further 

I have never built a Ponti so I sooo do not want to do an over kill build then hate how it behaves ! 

Kiwi

Casting dates of A094 and A114 means January 9,  1974 and January 11, 1974 respectively.

4X 7H heads were mounted on 400s. 98.21 ccs, 2.11/1.66 valves 4.86 valve length..

i found this very interesting artical on the 4x heads ...

https://www.hotrod.com/how-to/0312pon-4x-6x-racing-heads/

Then i went about cc ing what i have to prove what they are ... dont laugh guys its justA how i think .....

 

i sand blasted one chamber , valve springs and spark plug in place ...

 

while the boss wasnt looking i nicked some food colouring and a 60ml sringe from my hydros 

i could not find any plexi glass, so i used a cd case....

and this as a sealer for the head to cd case....

 the result ...i pumped 100mls into the chamber and i now know they are infact 98 cc chambers ..i dribbled a liitle ... cause i am old !!! and as you can see there is a couple of air bubbles in there .

it proved to me , i have 98 cc heads 98 mls = 98cc

not the 114 cc ones !

so i am super happy.... i recond these heads can be used... after crack testing !

I will need to have them checked for cracks and have guides, and hardened valve seats done  but i beleave they can work for this build ....

Edited April 20, 20251 yr by 64 kiwi boni

That is Actually... A Very good Accurate way to measure the Combustion Chamber Volume..👍👍

2 minutes ago, TWO LANE BLACK TOP said:

That is Actually... A Very good Accurate way to measure the Combustion Chamber Volume..👍👍

Thanks two lane, i only paid $400 nzd for these and i so could not justafy kre or eddy heads 

My whole goal here is to help pontiac guys use what we have !! and not go blow silly money on aftermarket gear if it can be avoided

gee i am slow !!! i got bubbles under the cd case because of surface tension !!!! ddrrrrr. i should have added a drip of dish wash detergent to the red water ! 

what kind of plumber am i !!! 

Note to any one who trys this in the future .... add a drop of good old dishwash liquid 

Edited April 20, 20251 yr by 64 kiwi boni

Kiwi..

This is probably a stupid Question..But I'm going to ask anyway...Did you Do your Combustion Chamber Measurement on Both of the Cylinder heads...??...In order to Insure that you have a Matching Pair...?? 🤔🤔

Edited April 20, 20251 yr by TWO LANE BLACK TOP

I love the way you checked the cc. Thats genius bro.

7 hours ago, TWO LANE BLACK TOP said:

Kiwi..

This is probably a stupid Question..But I'm going to ask anyway...Did you Do your Combustion Chamber Measurement on Both of the Cylinder heads...??...In order to Insure that you have a Matching Pair...?? 🤔🤔

Ah !!! No !

best I do the other head aye 👍
I will do that this morning 

Thank you two lane 👍

Edited April 20, 20251 yr by 64 kiwi boni

Thanks to the rain this morning 

my first job is to cc that 4x head 

the result....... drum roll .......its a 98cc chamber justA like the other !!!

note from above, i tried adding a drop of detergent to the coloured water.... didnt work !!! all it did was make bubbles under the plastic, so as you can see here , straight water worked perfect !!!

soooooo ! while its raining i decided to cc the 46 heads i bought for 50 bucks ! these are 1968 casting with 1.94 and 1.6 valves ....

 

This is where it gets interesting !!! these 46 heads are suposed to be either 96 0r 98 cc ... they didnt measure that !!! infact, i did both heads and they both measured 75cc !!! 

i kinda like these heads as they flow 10cfm more than the 4x based on  Rons pontiac pages. ( 181cfm as oposed to the 4x @ 171 cfm ) in stock configuration.. i am guessing that some where in their life they have been shaved to be only 75cc 

the other interesting thing is the 46 dont have the extra hole on the ends of the block for headers (see Pic) 

 

Edited April 20, 20251 yr by 64 kiwi boni

Kiwi

The missing or not drilled hole is not unique. I had the same problem on my 7K3 heads. My engine builder drilled them out. I suspect Pontiac did this depending on what the intended exhaust manifold was planned for the car.  There were stock log style manifolds and the RA/HO manifolds.

On 4/13/2025 at 12:51 PM, 64 kiwi boni said:

news update !!!

the 400 block has past crack testing and the machine shop want to know what crank, rods and pistons i am using  and the will sleeve all bores back to stock 

Two lane , whats your thoughts on a 4.5 stroker kit, zero the flat tops to the deck and look at using/ modifying the 4x heads i have ? 

the machine shop will want to do the sleeving and milling all in one hit so they are going to want to have the pistons on hand before they go any further.

They want to sleve all the cylinders?

On 4/19/2025 at 9:51 PM, 64 kiwi boni said:

i found this very interesting artical on the 4x heads ...

https://www.hotrod.com/how-to/0312pon-4x-6x-racing-heads/

Then i went about cc ing what i have to prove what they are ... dont laugh guys its justA how i think .....

 

i sand blasted one chamber , valve springs and spark plug in place ...

 

while the boss wasnt looking i nicked some food colouring and a 60ml sringe from my hydros 

i could not find any plexi glass, so i used a cd case....

and this as a sealer for the head to cd case....

 the result ...i pumped 100mls into the chamber and i now know they are infact 98 cc chambers ..i dribbled a liitle ... cause i am old !!! and as you can see there is a couple of air bubbles in there .

it proved to me , i have 98 cc heads 98 mls = 98cc

not the 114 cc ones !

so i am super happy.... i recond these heads can be used... after crack testing !

I will need to have them checked for cracks and have guides, and hardened valve seats done  but i beleave they can work for this build ....

Very creative With the cd Case and a syringe, might steal that one 😆

I have been using windshield washer fluid in the past.

15 hours ago, 64 kiwi boni said:

Thanks to the rain this morning 

my first job is to cc that 4x head 

the result....... drum roll .......its a 98cc chamber justA like the other !!!

note from above, i tried adding a drop of detergent to the coloured water.... didnt work !!! all it did was make bubbles under the plastic, so as you can see here , straight water worked perfect !!!

soooooo ! while its raining i decided to cc the 46 heads i bought for 50 bucks ! these are 1968 casting with 1.94 and 1.6 valves ....

 

This is where it gets interesting !!! these 46 heads are suposed to be either 96 0r 98 cc ... they didnt measure that !!! infact, i did both heads and they both measured 75cc !!! 

i kinda like these heads as they flow 10cfm more than the 4x based on  Rons pontiac pages. ( 181cfm as oposed to the 4x @ 171 cfm ) in stock configuration.. i am guessing that some where in their life they have been shaved to be only 75cc 

the other interesting thing is the 46 dont have the extra hole on the ends of the block for headers (see Pic) 

 

My heads are the same,no holes on the end, seems ok with stock manifolds but probably don't work so good with headers.

I have found that any head listed as this or that is not accurate, some are close but some are just wrong, need to measure everything and it's pretty interesting if you start playing with numbers just a few CC makes a difference.

Have you seen the compression calculator on summit racings web site? 

Simple and easy to use, interesting to play with Numbers there just a simple thing as piston height or head cc makes a difference.

4 hours ago, Andy H said:

They want to sleve all the cylinders?

Very creative With the cd Case and a syringe, might steal that one 😆

I have been using windshield washer fluid in the past.

yes Andy, they will sleeve all 8 bores, as it was explained to me, when 2 bores are sleeved there is core shift and this effects the next cylinder bore , so its a all or nothing jobbie 

4 hours ago, Andy H said:

My heads are the same,no holes on the end, seems ok with stock manifolds but probably don't work so good with headers.

I have found that any head listed as this or that is not accurate, some are close but some are just wrong, need to measure everything and it's pretty interesting if you start playing with numbers just a few CC makes a difference.

Have you seen the compression calculator on summit racings web site? 

Simple and easy to use, interesting to play with Numbers there just a simple thing as piston height or head cc makes a difference.

funny you say that Andy ! i did justa have a play with summits calculator, and with a 4.5 stroke and those 46 the comp was over 12.1 to 1 

59 minutes ago, 64 kiwi boni said:

yes Andy, they will sleeve all 8 bores, as it was explained to me, when 2 bores are sleeved there is core shift and this effects the next cylinder bore , so its a all or nothing jobbie 

funny you say that Andy ! i did justa have a play with summits calculator, and with a 4.5 stroke and those 46 the comp was over 12.1 to 1 

Sounds expensive to sleve 8 cylinders, cheaper to find another block?

I did quite a bit of running different scenario when I built mine, something else that helps apparently with detonation is squish or piston height but also affect comp.

You know you could run a really big can with that compression that will take care of it 😜 

If i had to guess, finding viable Pontiac cores in NZ is a wee bit tougher for Kiwi than for us.

9 hours ago, Andy H said:

Sounds expensive to sleve 8 cylinders, cheaper to find another block?

I did quite a bit of running different scenario when I built mine, something else that helps apparently with detonation is squish or piston height but also affect comp.

You know you could run a really big can with that compression that will take care of it 😜 

i am very lucky as my son in law is a machinest  and the sleeving/boring/decking will cost $1200nzd including matching to the pistons i supply .

i will also supply the sleeves 

 the block cost me nothing and no joke Andy, finding 400 blocks in nz is crazy hard !!! 

'yes i could get one from your little island but that will cost to ship !

 this block has history with a good mate of mine and if i can save it, i will forever be able to say it was out of a drag racing t bucket that all our club knows ... so thats a factor too 

8 hours ago, Frosty said:

If i had to guess, finding viable Pontiac cores in NZ is a wee bit tougher for Kiwi than for us.

snap !

8 hours ago, Frosty said:

If i had to guess, finding viable Pontiac cores in NZ is a wee bit tougher for Kiwi than for us.

anyone who has one wont give it up !!! hens teeth even

 

7 hours ago, 64 kiwi boni said:

i am very lucky as my son in law is a machinest  and the sleeving/boring/decking will cost $1200nzd including matching to the pistons i supply .

i will also supply the sleeves 

 the block cost me nothing and no joke Andy, finding 400 blocks in nz is crazy hard !!! 

'yes i could get one from your little island but that will cost to ship !

 this block has history with a good mate of mine and if i can save it, i will forever be able to say it was out of a drag racing t bucket that all our club knows ... so thats a factor too 

snap !

anyone who has one wont give it up !!! hens teeth even

 

That's Awesome, sounds like you are going to be taken care of properly 😀

Here it's getting hard to even finding a machine shop they are retiring one after another kind of like trans guys.

Kiwi...

Justa Make sure that the Main Bearing Caps are Thoroughly Inspected and Magnufluxed as Well...it is Very Important...Stock type Main Bearing caps (2 or 4 bolt) that Have been Subjected to Hardcore...Ultra Severe/High RPM..Loading/Unloading/Racing Conditions...Etc.. Have a Propensity (Unseen to the naked eye) to Develop Hair line cracks Across the Center of the Main Caps...And WILL Catastrophically Fail...Any Extra $$ spent on doing that...Is Cheap Insurance...🏁🏁

TLBT...

 

Edited April 23, 20251 yr by TWO LANE BLACK TOP

1 hour ago, TWO LANE BLACK TOP said:

Kiwi...

Justa Make sure that the Main Bearing Caps are Thoroughly Inspected and Magnufluxed as Well...it is Very Important...Stock type Main Bearing caps (2 or 4 bolt) that Have been Subjected to Hardcore...Ultra Severe/High RPM..Loading/Unloading/Racing Conditions...Etc.. Have a Propensity (Unseen to the naked eye) to Develop Hair line cracks Across the Center of the Main Caps...And WILL Catastrophically Fail...Any Extra $$ spent on doing that...Is Cheap Insurance...🏁🏁

TLBT...

 

I will txt the son in law right now !!! 
thank you Two  lane 🙏

Edited April 23, 20251 yr by 64 kiwi boni

I have been looking around at crank shafts and piston combos and talking to the team at Tin Indian, we came up with a combo and they started by getting a quote for freight to Nz...... sit down !!!! $2300 usd on ups! 

for that i could fly to ozzy pick up Fitzy , we could both fly to Lodi Ohio grab the parts and fly home !

lets justA say, buying parts for the engine is a work in progress 

Soooooo, i am still talking to the team there and we might be able to find another option.... kiwi shipping where my 57 went to in new york, there depot maybe a cheaper option .... just wayyyyy slower. a trip on the atlantic  ocean down through the panama canal, to the pacific ocean.... and down under 

Edited April 26, 20251 yr by 64 kiwi boni

Wait a minute - US$2300 just for freight???

Screw that. Order the bits, fly over, get drunk, have a heart attack at Tony's, shove those bits in as checked luggage and you're done. Yes, take me as well. If they're gonna pump your stomach and defib you, they may as well make it worthwhile and do both of us.

1 hour ago, Fitzy said:

Wait a minute - US$2300 just for freight???

Screw that. Order the bits, fly over, get drunk, have a heart attack at Tony's, shove those bits in as checked luggage and you're done. Yes, take me as well. If they're gonna pump your stomach and defib you, they may as well make it worthwhile and do both of us.

Ah true !

but who takes the pics to stick on fp ????

frostyyyyyyy 😜