jdm b18b compression ratio vs usa

[unknwnturbols]

I have a 1995 Integra ls just installed a turbo setup and busted the number three cylinder wall. All the pistons look fine no melting or holes but the cylinder wall just gave out it looked like. I was just wondering if a jdm b18b compression ratio is higher than an amercian b18b and if i should install a blockguard in the motor before boosting it again.

 

[jeterkm02]

jdm is has higher compression than usdm.

 

[unknwnturbols]

do you know how much higher and should it be alright to boostor should i get a cometic head gasket to lower the compression one point?

 

[Slammed90Lude]

what kind of fuel management were you using? and how much boost were you running- a stock b18b should be able to handle a pretty fair amount of boost on a good tune

we're talking about a difference in compression of 9.4:1 JDM vs 9.2:1 USDM either one of those are pretty boost safe numbers- i would suspect insufficient fueling and one hard knock could have cracked a cylinder wall like that, but i would doubt the slightly increased compression ratio would

 

[unknwnturbols]

i was running a 12 to 1 fmu cartech w/ 440 rc injectors and a 255 lph fuel pump with a afc controller but we were trying to tune it when it blew up any advice would help me with this so it does not happen again but i ordered a wastegate off of ebay and it was a 15 psi wastegate so it was 15 pounds of boost. This is my turbo setup t-3 t-04 hyrbrid garrett tial wastegate i got a new one .6 bar, cartech fmu, stainless steel manifold, tial blow off valve, missing link, 3" down pipe, 3" thermal full exhaust no cat, skunk 2 intake manifold, bbk 70 mm throttle body, aem cam gears. if anyone could give me any advice i would greatly appreciate it. Ohh yeah i did not retard the timing either and what type spark plugs should i use and were should i set the cam gears

 

[Slammed90Lude]

dude i promise i will respond to your post in the morning with pertinent information, but i am too tired to give you the information you need and read through your post

unless B beats me to it

 

[Slammed90Lude]

chances are tuning a T3-T04 at an initial 15 psi of boost is what caused the problem- i personally would recommend ditching the FMU and at the very least start running one of the free rom editors, or if you have the cash, hondata

also, get an electronic boost controller so that you aren't stuck at the boost level of the spring in the wastegate- plus, this way you can start out by tuning it at a lower boost level, like the 9 psi of boost your .6 bar wastegate is set at- after that initial tune, cranking up the boost and adjusting fuel maps and timing won't be nearly as hard, although i think 15 psi might be a little too much for that motor, with a good hondata tune, it should run (for at least a little while )

you might want to consider running spark plugs that are one heat range lower, since the increased cylinder pressure obviously creates more heat (PV=nRT) and you should def. look into some way of cooling the air- you are running that turbo fairly hard to get that boost level, and as such, you're heating the air fairly significantly- not only would an intercooler help you make more horsepower, but it would help the motor to be less detonation prone

hope that helps

 

[unknwnturbols]

sorry forgot to tell yah i do have a pretty big intercooler and a turbo xs manua high performance boost controller. Do you think it was a fuel problem or something but the car was running great it just shut down it did not knock detonate or anything like that it was like it just cut off no noises or anything there were no signs on the pistons of melting or anything and what is a free rom editor and where could i find one and what price range are we talking. Also do you know what the spark plug number is for one step colder for my car i was running ngk v power plugs before.

 

[saturn_boy96]

what kind of gas were you running?

post pics if you have them.

 

[unknwnturbols]

i think it was 89 the car only ran for about five to ten minutes
soory no pics but it took a big hunk out of the cylinder wall looks like someone too k a bite out of it

 

[posol]

fmu = fucks motors up.

end of story.

if you want to feed it a lot of air, you need to feed it a lot of fuel too. the fmu is only good for small turbos and 10psi, or medium turbos with like 5 psi. after that, they just can't supply the fuel you need.

you ran lean, detonated, and took out your sleeve.

a block guard would have only helped in aiding to the heat collection.

 

[saturn_boy96]

Originally posted by unknwnturbols@May 5 2004, 06:16 PM
i think it was 89 the car only ran for about five to ten minutes
soory no pics but it took a big hunk out of the cylinder wall looks like someone too k a bite out of it

89 octane owned you. period. you simply can't run boost on that crap.