I'm planning on modernizing an old low-compression engine

>>17355803
Theres some head shaving process that raises compression I think if your valves will clear.

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what engine is it?
start with porting, bigger valves, and for sure a nice cam.
you will want to balance the internals too.

i ported this jeep head, exhaust first i removed about 3lbs alone on that side. really woke it up

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>>17355815
i suggest you prepare many, many hours to porting. this was perfection after about 2 weeks on and off, again exhaust first.

there is more power to be made in porting than any header or ITB setup

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for many many engines porting templates are available. people have been there and done that, and made a template to follow.

obviously not the case with a jeep head

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and face it, custom pistons arent that much more money.
just get in contact with your fav piston company. i used childs and albert

>>17355815
It's a Mercedes M103. People just usually slap turbos on these, but I'd like to stay N/A for this build. Anyway, nice work on the Jeep.
The factory heads on these engines apparently flow really well already, but I know a professional who'll do the porting and other head work for me.
My concern is that with a hotter cam the dynamic compression ratio drops too low.

>>17355860
Can you give any figures about how much a set of 6 custom pistons will cost?

Pistons are your only solid way to make more compression. Shaving the head changes your cam timing and isn't very effective. What engine are we talking about here

>>17355892
contact mahle? dont they make the oem ones?
you can really pretty much go with any company if its custom. i paid about $90 each

>>17355803
>in this case there are no aftermarket pistons available.
Get custom pistons you fucking mongoloid.

>>17355928
u mad

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>>17355934
custom lightweight pistons like these?

>>17355934
Mad that you're fucking dumb as hell

>>17355909
I was under the impression custom pistons are really expensive, but that doesn't seem too bad. Might have to go that route then.

>>17355803
literally any decent piston company will make you pistons

>>17355954
you dont know unless you ask several companies for quotes.

>>17355909
$90 a piece is about right for aftermarket pistons.
Off the shelf aftermarket and custom pistons take about the same amount of effort for a manufacturer. They already have a slug forged, its just changing the CNC lathe program from .0125 to .0375 type of shit.