what to bore motor to

[emd513]

alright guys just got me a freebee motor from a friends friend n am going to build it. my question is im wanting at least 200+ to the wheels and still be able to throw a turbo on in a year when i get all the parts for it. i was planning to punch it 20 so i didnt have to sleeve but to do it n hit a respectable 200 i would need high compression setup. but can i just bore like 30 r 40 n sleeve it n still get my target with a low compression lets say 9 to 1 r is that going to be too much for when it is turbo. any response is appreciated as long as its not a bullshit remark thanks

 

[nicoalex2]

What motor? We need more info and better grammar.

 

[BigMac88]

Short answer: No. You're wasting your time and money.

You need to do a lot of research. Building a motor for a naturally-aspirated setup follows a different philosophy and application than setting up a motor for boost. You may as well save you're money and boost it if that's your long-term goal.

Start by researching details of how a motor works, then research the differences in extracting NA power vs. FI power. We have a lot of great info in the All-motor and Forced Induction forums here on CI.

If you were to build NA, you'd require cams with a lot of lift and duration, a quality header, and high-compression pistons. Even if you bored the motor out to 84mm (2.0L), you'd still need high compression pistons to pull 200whp out of it.

Turbocharged setup obviously don't use a header, but they also require cams with a lot of overlap - cams that are completely different than those used in an NA build.

I could write you a 30 page essay on how all of this works but you wouldn't learn anything that way. The point I'm trying to make is, what you want to do makes absolutely no sense. You can't just 'throw a turbo' on a NA motor and expect it to work. They're two clashing build philosophies that have equally effective but different outcomes.

Research, research, research....

 

[emd513]

i realize that they r two totally different ways to have to build them to get either to work. n its a b18a1. i know the cams r diff n pistons r as well, thats why i was asking if it was possible to make it with a low compression piston n still hit the 200 mark with out having to go way out of the way of putting a total different setup later. my problem with saving my money is unless i get another job making descent money it will take like 2 years to get it, n i really need a new motor now. its going to be a budget build but still get the parts i need to make sure the thing holds together especially the way i drive. this is my first 4 cylinder motor build. i use to be all about chevy small blocks and that was it till i rode with my buddy n this car. n with a v8 its bore the fuck out of it n sleeve if u go to the extreme n then port n polish the heads to the maximum n u get 900 + to the wheels with a little nitrous. so if building this one means later i will have to rebuild so i can make the turbo work the way it is attended to work then thats what i will have to do but i will not put a stock motor back n to a car ever. n my opinion theres no point n spending the time of rebuilding a switching motors n a car to go right back to the stock setup u started with if ur already have it ripped apart. might as well make her scream with as much power as possible

 

[emd513]

another question n if u do not want to answer then will u direct me to the page where i can read n find out. what is a good compression if i decide to just run nitous right now with this motor n i know some other things will have to be set for it n all that good stuff but what is going to be too much for these motors. will 13 to 1 be too far should i just stick with a 10 to 1, and it would be the maximum of a 100 shot probably just use 50 unless im going against someone with a whole lot more power.im not opposed to using nos at all since i can get those fairly cheap. hell if i build the motor to the extreme n use nos i might not even go with a turbo. just want to end up keeping up with the guys n there stangs n camaros with 400 horsepower. its fun to fuck with them n a honda. they get all upset when u pull up with one a walk there ass especially the rednecks around here.

 

[GSR-TURBO-DC]

9:7:1 is an ideal turbo compression, that will make good streetable power all motor.

The cool part is that i have some barley used CP forged Pistons 9:7:1 83mm BORE. for sale. only aasking $320 Shipped

 

[mirrorimg]

Your B18A1 will not make 200 to the wheel without forced induction. It just doesnt happen on a streetable motor. I have a b18b1 and I am shooting for 180 whp, and thats with the best flowing non-vtec head around bolted to it.

Also, low compression on a non-turbo motor will not make you much power. N/A motors = high(er) compression, so until you were to turbocharge your car, you will not be leaving anyone in the dust.

If you want a turbo motor, build a turbo motor. If you want an N/A motor, swap in a VTEC b series and build it, do an LS/VTEC setup, drop in an H-series, or drop in a K-series.

I would also like to mention that I read about 3 lines of one of your posts. I gave up, because it was honestly painful to read that lump of text.

 

[emd513]

Sorry that in was so hard to understand. I use a cell phone for the most part n sometimes I get ahead of myself while writing n babble on different subjects. I have talked to several people with street motors that say it is easy to push 200 but u have to be on a high compression set up n have the right work done with tuning n engine mods. I have decided to go all motor n throw nos to it n then later on build another for turbo. Thanks for the info though it has helped me to decide the best way to go right now. Sorry for babbling

 

[HKDxSAVIER]

dont mean to steel your thread but real quick question?

what would i have to bore my b20b to get that good streetable turbo compression?
stock compression

8.8:1

how much am i looking at spending and what if i turbo withought boring?

 

[HKDxSAVIER]

ok ok nm about my post up there

i looked at the b20b motor 1999-2000 and its at 9.6.1 compression
im in the clear to turbo right?

 

[User Name:]

IMO, A B18A1 isn't really a good starting point for high power especially in the head. There are way more parts avalible for the B18B if you could go that route. And Big Mac is right. RESEARCH!

 

[mirrorimg]

ok ok nm about my post up there

i looked at the b20b motor 1999-2000 and its at 9.6.1 compression
im in the clear to turbo right?

Sure. The b20 has thinner sleeves than a B18, so it would be less optimal, but you get more displacement and there fore torque. If you really want to push a lot of power you would need to re-sleeve the block, and at that point, it doesnt matter what block you have.

IMO, A B18A1 isn't really a good starting point for high power especially in the head. There are way more parts avalible for the B18B if you could go that route. And Big Mac is right. RESEARCH!

B18A1 is the exact same as the B18B1, and has the same aftermarket support.

The big limiting factor on LS motors is the fact that they have very poorly flowing heads. Less air making it into the combustion chamber= less power.

 

[User Name:]

Sure. The b20 has thinner sleeves than a B18, so it would be less optimal, but you get more displacement and there fore torque. If you really want to push a lot of power you would need to re-sleeve the block, and at that point, it doesnt matter what block you have.



B18A1 is the exact same as the B18B1, and has the same aftermarket support.

The big limiting factor on LS motors is the fact that they have very poorly flowing heads. Less air making it into the combustion chamber= less power.

I thought they were the same bottom end but with diffrent heads. Cant swap the valve covers.

 

[emd513]

That is the reason I'm going to port n polish it. N the right way not that crap where they just take a drimmel n sandpaper. There's a guy here that I have heard is awesome on doing it. I'm going to see how much he charges

 

[BrokenTalon27]

That is the reason I'm going to port n polish it. N the right way not that crap where they just take a drimmel n sandpaper. There's a guy here that I have heard is awesome on doing it. I'm going to see how much he charges

Make sure he does it on a flow bench.