engine id info neaded for aussie lad

[teza75]

hi guess i need to to some part ordering soon for my v6 turbo engine , done heaps of research and keep on getting confused, i need to know what i got and what its out of , this is what i have block cast number is 25506818 i get confused here as the 4.1 and 3.8 .and i cant see any 3.8 or 4.1 on the rear bellhousing flange i found heads cast numbers are 25506293, are these good heads to use,and i aslo found casting number 25507801 on the exhaust header, any info much apreciated .i know its a turbo block but thats as much as i know, any one know whats a safe limit for the overbore , also i am looking at ta performance gear for it , do i need to go all out on the block to handle 600 rear hp i am thinking the basics looking at good bearings and a gridle and new set of pistons

 

[teza75]

i forgot to mention it was factory 4 barrel draw threw tubo setup, i am thinking of its a 1983 v6 turbo but i just want to be certain as its along way to go for a exchange part if i stuff up on the part list

 

[charlief1]

This should help.

Buick V6 History

 

[RIFF RAFF]

I was

Gonna say hot air block . But charlief1 sent you down the right path ..

 

[teza75]

i printed all that info and lots more but it gets confusing as it states the block go from 1979-1983 , but also in a different site gnttype also says the block number is used on a 4.1 aswell

 

[charlief1]

Looks like the casting was made from 79 through 83 and is a NA and turbo block. Since it was used in both it should be good to use.

 

[RIFF RAFF]

I think hes looking for

looks like the casting was made from 79 through 83 and is a na and turbo block. Since it was used in both it should be good to use.

3.8 or 4.1 .

 

[charlief1]

3.8 but measure the bore to make sure.

 

[teza75]

thanks guys for your help , yeah will dig in a bit deeper into the block and see what i can find as i cant find any markings to say if its a 4.1 or 3.8 on the flange at the rear, but for what i can see the 4.1 use a differnt head to 3.8 and the cast number on the heads match a 3.8 so i guess thats what it is

 

[teza75]

better to be safe than sorry a long way to send parts back

 

[teza75]

with that being either a 4.1 or 3.8 , they are the same rolled fillet crank right so how did they get the extra cubes , by rod lenght or by bore size , surely it would be safe to take it out to a 4.1 , as it does have good gap between the the bores from one cylinder to another

 

[charlief1]

Bore size.

 

[teza75]

thanks charlief1, great help

 

[charlief1]

Just Charlie and if you're plannning on going stock draw through then click on the second link in my sig. I'm sure it will be hard to find "over the pond" but it's a much more efficient turbo design.

 

[teza75]

i have a 4 barrel manifold i think its holley style and i am going to take it my machine shop thats finishing me 700hp rotary gemini they are good with the tig ,i am a welder fabricator so was gona whip a mounting plate and try to attach it to the 4 barrel manifold and the drill and weld in boss for the injectors and convert the 4 barrel to direct sequential injection or batch fire not sure yet,not to worried about hangin the supercharger threw the bonnet little , just a little worried on how the throttle body on the eaton supercharger will handle the extra boost of the turbo weather i will need to put a stronger spring on so pressure doesnt open it more than i am pressing on the load pedal

 

[teza75]

forced intduction technology here say it will work and are keen on lending a hand and witts to make it work,

 

[charlief1]

Pics would be really helpful here if you can post some. I should be able to tell you which intake you've got.

 

[teza75]

hi charlie than manifold is a Offenhauser Intake Manifold working on the pics

 

[teza75]

hope these work

 

[charlief1]

Get some pics up because there're 4 different offy intakes. You need to have the right one to make it work or the intake ports won't match up.

LOL You were posting pics while I was posting. That's the interum intake and it fits all of the V6 designs. You will probibly need to match the intake ports but that's just about it.