please read fully. after much reading and creeping forums i have decided i want to settle this for myself. i recently bought a 91 civic si and im looking to get 250-300 hp out of this car because tbh im tired of getting squashed by the rednecks with giant desel trucks. so far i have bought a standard b18 motor and am opening it up to check if it needs to be bored or just honed. whatever the case i plan to put in high compression pistons (unknown brand) and forged rods. i have a b16 vtech head and plan to go aftermarket valve train as well as skunk2 cams.

so far all i have seen is that is all i need to get that kind of power is high compression, better flow and aggressive cams. now im constantly seeing conflicting information most say it cant be done figured i would duke it out myself here.

if you have any suggestions tips or just want to burn this thread any advice is welcome

 

Check the NA forum, they would have more information on the motor set up most likely.

I will say you will not get 300 HP out of a B18, 250 is tough enough. Good luck.

What is 'unknown' brand? Knockoffs? That's a terrible idea if that is what you are using. You'll need crazy cams too, bigger than Skunk2s I'd imagine. The VTEC head will need a lot of work too.

 

ok will do thanks. not knock offs i think they where gsr pistons we pulled from another motor years back. what kind of work are we talking about only seen cams and better valvs+springs in most forums

 

Why NA?

That's the most expensive route to make a heavy 91si quick...

Just boost on a b18c.

 

https://honda-tech.com/forums/showthread.php?t=3220625

Copy this build to the T. Enjoy the 220whp. Trust me, it will be more than enough in an EF.

 

yup, just boost that B18 (is it A B or C?)..some pistons, rods and a block guard, and a turbo kit and you're good. hell I prolly have all that stuff sitting around from my B-series days just PM me if you decide to go the turbo route with pistons and rods.

easy power bang for the buck...you can def take down the Diesel trucks...boost 15-20 psi with block guard and the lil Si will fly.

 

there is a few reasons why i dont want to boost. im at a higher elevation with brutal winters so chances of blowing a turbo are pretty high and at least this way i have a strong start to turbo with later.

side note would 94 integra trailing arms fit my 91 civic. having trouble finding a compatibility chart

 

Turbo is MUCH better at altitude than na. Not sure how cold winters blow turboes that's news to me.

 

Yep. If cold winters killed turbos, they'd never sell factory turbo cars up North.

 

for a all motor setup..... using a straight up b18a1/b18b1 will never make 200 without a thousand in machine work to the head alone not including a 100% build to the motor...

if bumping the compression in block and slapping a vtec head on to go lsv.... it will still be hard to hit the 250 marker. you may be around 160hp with a ls block and b16 head, so bumping the compression and building the head along with a TUNE you will be lucky to hit 185-195 maybe a few extra....

personally the easiest way to reach 250-300 on a N/A setup would be H series or K series. also note that lsv is not the most reliable due to a lot of factors...also note that building a motor with higher compression or harder valve train etc will be more wear and tear, and if planning to daily drive the motor reliability will come into play

be realistic in the goals you are planning to set. it may be cheaper to buy a stock K with 200+ and have a shop toss it in.... compared to what... like... 800$ bore/hone/mill aftermarket pistons/bearings/rod bolts.... 400$ valve job/surface/pnp... vtec cams twice as much as non vtec... so another 1500$ in head internals.. and then easily 1k in a GOOD tune aka hondata or similar and a shop that will charge 400-600 to make it street reliable

 

Turbo is the most cost effective route believe us. I built a budget 200 whp B20v, it cost me about $4k doing all wrenching and assembly myself. If you want 250+ you will need a custom ported head, aftermarket Intake manifold, $800 headers, etc etc....

Or, you can build a cheap B18 turbo and run those numbers all day. Honestly i would leave the longblock alone as long as it has decent compression, slap a turbo kit on the bitch, get it tuned for 250whp and spend maybe $2500. For the price of blockwork and aftermarket stuff, you could swap out the longblock if it blows lol

Also, yes, civic/teg trailing arms are the same, the toe links need to be swapped tho.

 

I would like to chime in and say 250 NA HP is way cooler than 250 booster HP. I've seen ~200 wHP B20VTEC EFs run much quicker than similar HP turbo'd EFs. 250 wHP NA is a lot of power and would be very quick. I'd settle lower if you are just wanting to go fast. If you are here for bragging rights on maximum HP, go with a turbo and put down 300+ on a stock block.