Ok guys so check it out....My 1.6 liter motor is dying slowly and i last dyno'd at 209whp with 196wtq with the greddy kit. I now want 275-300whp and want your opinions on which route to take.

1) buy a motor thats been imported from japan for 500 bux with low miles and good compression (its a local pick up for me so i can go check it out). Keep my greddy turbo and go with a 19T compressor wheel

2) Use the 1.8 motor in my garage that needs a rebuild. (came off a 95 miata) and go with a bigger turbo.

3) Just rebuild my 1.6 liter motor thats currently in my car and get my nice compression numbers back. (keep in mind i will have to change the crankshaft because its a short nose- even though i have no crank wobble or anything)

I dont want to spend too much money on this btw so any advice will be taken into consideration.

Only reason why i want to avoid the 1.8 route is because im scared it will cost me too much.

 

rebuild the 1.6L with better rods and better rings.

that will be the cheapest way, you can push the GReddy to a tad over 250rwhp, but the turbo will need upgrading to go further.

 

Rebuild and get better pistons, rings, and rods. Then you know what you've got.

 

So just change the rods/rings? I already know by opening the motor i will want to get new pistons w/rings/rods,valves,valve springs.... i just want to know is it really necessary?

 

You don't have to touch the head. But the ringlands/rings are the weak link. They go before the rods, but the rods themselves are thin comparatively.

you could get away with a light build to make sure the block itself can handle things, then it's a simple of finding a turbo that will support the goals, you can crank the 15g to about 15-16psi and reach 250-260rwph, won't see much higher than that unfortunately.

but, while you're at it, mild headwork will make that turbo spool much better and even at 250 with better low-end from 210 and the odd spool will be worlds difference.

 

Trade/sell your 1.8L for a 1.6L and do a mild build of the 1.6L on the side so that you can still drive your current car (and as hard as it is to do, turn down the boost just a notch so it lasts ever so much longer.)

I'd normally say build a 1.8L since you have it and a conversion is not a big deal, but then you'd need a new exhaust manifold and while your at it why not get a better turbo, etc... so it could get pricey overall.

Building an engine is a very slippery slope so if cost is an issue, just doing a mild shortblock build is your best bet. ~$700-800 for the CAT rods and Wiseco pistons + the cost of reboring/honing the cylinder walls + balancing + assembly + refreshening (seals/TB/WP/etc...). Headwork is $$$.

If you are more serious about breaking the 300hp mark, then I'd suggest that since you'd need a different turbo anyway, a different exhaust manifold would give you better options so you might as well build the 1.8L for the extra displacement. Not that you can't do it with a 1.6L, but the extra 200cc of displacement never hurts.