well im having some major issues tunnign part throttle but that a whole new post ,

im running a f20b 11:1 comp all stock
stock header into a not so great exaust (2.5 inch but its botched up)


no on my logs im showing from 7000 to 8000rpm it goes half a point richer mabye more ,

now im concerned as to why this is happeneing .

heres my thoughts

1. 42mm is far to small for 2.0 at 8000rpm
2. not enough air space around inlets
3. stock header and shitty exaust system is limiting
4. PCV system is not hooked up right now as i plan on haing it vent right into the collector (crank case presure could be limiting?)


any thoughs , and could ignition timming be and issue (stock p30 table eing used )

 

Ignition timing is always an issue. I'd get a decent header and exhaust on it, it should help at high rpm's quite a bit. 42mm shouldn't be too small without additional airflow modifications.

 

thanks kendall,

im going to start buiklding a header this winter (cant afford a real one lol)and making a new exaust

 

any other thoughts .

i would assume the motor would need more fuel as rpm increas , is there somehting im missing or is there def something wrong

 

there is a point where the motor will need less fuel and you probly passed it a while before 8000rpm , unless you have some crazy cams....what is factor rev limit on that??

 

the f20 factory is 7800,
hard to say if it keeps making power ater 8 but i now it feels good till 8000

it uses prelude type S cams stock , there not huge but there not small ,

 

more then likley you would need to pull fuel back after peak hp wich would be alot sooner

 

thanks mark , im onna have to get it on a dyone soon but it will have to wait till next year , whos got a dynojet near you

your dan's cousin right ?

 

In researching with a well known engine builder, he confided to me that 42mm would be too small for a motor wanting to breathe over 7k rpm (1.8L)... fwiw...

I'm using 48mm on my 1.8 and am having my own issues, however.....

 

what are you using to tune your fuel? uberdata, crome, other EMS?

 

sorry im using crome with itb tools

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Black R &raquo;</TD></TR><TR><TD CLASS="quote">In researching with a well known engine builder, he confided to me that 42mm would be too small for a motor wanting to breathe over 7k rpm (1.8L)... fwiw...

I'm using 48mm on my 1.8 and am having my own issues, however..... </TD></TR></TABLE>

crap, its weird , but youd think that having twice the throttle area , but it makes sence , im looking for other alternatives as we speak cheaply of course

 

when tuning the '96 spec JDM ITR with TWM ITBs we first noticed a power loss of 5 whp but gained 8wtq when comparing runs against the OEM IM. Once you have the head completely worked over ina race fashion that is able to with the ITB application. You will need Large cams and good ignition timing. That is what is need to make the real power

 

If it's a really well put together setup, you can get truly stupid amounts of air velocity at high rpms, and only be moderately restricted from about 7k to redline depending upon the exact setup. On a 2 liter they really will run out of flow somewhere between 7800 and 8200 depending upon the exact setup though. Setups like this tend to like a lot of overlap and exhaust restrictions really play a major part in killing horsepower.

But this is all assuming that it's a really well put together setup.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by machine4321 &raquo;</TD></TR><TR><TD CLASS="quote">thanks mark , im onna have to get it on a dyone soon but it will have to wait till next year , whos got a dynojet near you

your dan's cousin right ?</TD></TR></TABLE>

ya amongst other things lol

 

well the stock h22 mani is pretty crapy stuff ,
no tto mention i have a 2 1/4 mufler n a 2.5 crush bent exaust , and the shop that did it used shitty claps and many crush bends by the rear end , i hope to have all this cleared up by next season ,

ive got some extra money and im debating on crower 3s
or smsp or rmf header .

i was planing on building my own 4-2-1 and save some money , i still dont know if i can afford the big dog headers yet