jay0heavenly

Okay... I (incorrectly) thought engine building was mainly to have forged internals for when you go FI and not necessarily for hp gains.[&:]

Eventually (in a year or 2), I wanna go with the STS twin turbo setup...and I wanna go with forged internals, but I have no idea what "engine building" entails...lol

Help a newbie out! What do those #'s mean? (298, 302 etc.)[&:]

A_J

Well, that's a really open-ended question.. engine "building" can be from mild to wild - a simple rebuild all the way to swapping out to forged parts, altering bore and/or stroke, etc... then you get into porting to optimize airflow, blueprinting and balancing, etc.. volumes can be written, I'd seriously suggest a book or wikipedia to get started.

And 289, 302, etc. is the cubic inch displacement of an engine - compare to the metric expression, a 302 is equivalent to a 5.0 liter, etc. Our 4.6 liter engines are roughly equal to 281 cubic inches - it's a little over 60 c.i. per liter, so I use that for rough conversions.

explict

When building an engine for forced induction (supercharger, turbo..) you want a lower compression, I think our cars are somewhere around 9:1? But if you want to stay naturally aspirated (no turbo or supercharger) you want to build high compression.

The compresion ratio our cars have is pretty forced induction friendly.

jay0heavenly

ok... thanks for the help so far... I've heard that people don't suggest going higher than 289 b/c they ran into problems going bigger...any insight on this?

06Saleen3V

1L=60.4 cubic inches of desplacement

ndgoalie35

Most stroker kits are around 302, soI dont see the problem going greater than 289.

A_J

ndgoalie is on the right track when speaking specifically of the 4.6 block, 302 should be fine.

Now if you're speaking generally, well you'd eventually run into issues making any block have significantly more displacement than the design can handle - try to get extreme with bore and stroke and you can start running into issues such as cylinder walls too thin, interference from the stroke being too long and pistons getting stressed, etc.

But a good rule of thunb for the uninitiated would be to go with a stroker kit from a reputable source - they've likely sorted out any potential issues. Also note that displacement, and compression ratio, can be altered somewhat by the choice of heads (combustion chamber size).

ndgoalie35

You can always take the easiest route and just buy a stroker short block, then you will only have to chose a high compression or a lower compression for FI and not have to worry about the walls being too thin.

acdc163

Just wanted to say that those are sweet looking rims!!

TexStang06

wait for Fordfanboy to post in here, he's one to talk to about built motors. I think he had a 302 stroker at some point, but is now with a 289 I believe, which is supposedly better because you can leave the knock sensors on.