has any one built a 2.8lt v6 ?

[ARQ164 Shane]

Hi guys ,
has any one built a 2.8lt v6 ? I'v been tolled that if you put 3.0lt pistons in a 2.5lt you get a 2.8tl ?
is it that simple or is there more to it.

[Duk]

Hi guys ,
has any one built a 2.8lt v6 ? I'v been tolled that if you put 3.0lt pistons in a 2.5lt you get a 2.8tl ?
is it that simple or is there more to it.

By simple, do you mean, machining the block to accept the 3 litre liners?
Technically lots of work for a short stroke, big bore Alfa engine. To get any real advantage from this combination, you'd also be looking at adopting the bigger valve 3 litre heads.

Easier ways to achieve power than this combination.

[ARQ164 Shane]

I would like to use the original block so all the numbers still match

[aggie57]

Yes, been done many times.  You're probably best to search the BB.  For example:

http://www.alfabb.com/bb/forums/alfetta-gtv6-1975-1986/147585-boring-out-86-2-5-gtv6.html

[Storm_X]

So with a 2.5 block you machine it to suit 3.0 liners. So can you use the 2.5 crank and Rods , then 3.0 pistons ?

[Darryl]

Ask Richard Anderson. He has just built a 3L (changed crank as well) from a 2.5. However, he needed to do this to be able to run a 3L in historic rally - where engine internals are free but you need to start with stock engine for the car. I'm not sure if the work to go to a bigger bore would be worth it when not driven by trying to "optimise" under these rules.

[ARQ164 Shane]

I found this up on the 2.8 looks pretty good ; http://www.alfabb.com/bb/forums/picture-room/48677-alfetta-saloon-2-8-v6.html

[Beatle]

I would like to use the original block so all the numbers still match

A lot of hassle just to keep the numbers.  Do you need to keep numbers for originality, or just so you don't have to bother the rego authority?

I would think it better and more economical to work on a full 3L conversion and keep the original engine, and keep it original

[wankski]

yes... it's been done.. back in the 80s a small engineering firm in germany called 'gleich tuning', the man behind it all was Deiter Gleich, he upspecc'd the 2.5 as far as it would go before the 3.0s were around...

... the gleich engine featured bored out block + 93mm 10.5CR pistons, special cams and enlarged valves and playing with the l-jet system... apparently good for ~185-190hp up from, in reality ~155hp of the original.

this was not a 2.5 with 3.0 pistons... looking at the CR will tell you that, plus a belive gleich used forged items

anyway, when the 3.0 came along it made it all moot. sure, there were some advantages to the gleich, with its 68mm stroke (same as 2.5) and the big 93mm forgies, it was hugly oversquare being rev-happy... but in the end, it was a lot of work and a lot of $$ on pistons and custom cams and head work... when the stocker 3.0 made the same power and superior torque totally stock... u do the math...

today, the availability of 3.0 and even 3.2l 24v v6s with far better digital injection makes it redundant..

i can accept wanting to keep the engine original, but if you do push it to a performance tune, good chance of trashing it and ruining the originality anyway... best off keeping it safe and sound and swaping in a stronger motor... a simple 916 gtv 3.0 24v v6 conversion, will EAT anything you could do with the 12v for breakfast at much less cost.

155hp vs 220hp stock... game over. Been seeing such engines these days for sub $2k for a good example - check the internals, slap on a new WP and timing kit and pair of head gaskets, do the RWD conversion and you're in business.

if you are hell bent on it... there is another way... a 3.0 engine with a 2.5 crank... the CR will drop and so u will need to offset the rod small end to compensate...

[BradGTV]

dont really understand why you would bother. i can see the point of doing the opposite (2.5 crank in 3.0 block to give low comp on standard parts, then add boost  )

ive got a complete 164 3.0 surplas to my needs. (im going 24v) urs for $500 and all the parts u need to put it in a 75 i can throw in for cheap.