im a bit confused here!!

[bigboost]

right, i need some help if some dont mind as the search button hasnt helped this time.... where do i start. lol. i have no probloms with my car as such, its just iv got a bit stumped, had my car custom mapped running 15psi, and hold quite well, recently i had a small leak in my custom fmic, only audiable when cold,, anyway i tryed finding the leak but couldnt, so i went back to standard smic so i could inspect the pipes properly off the car, now with th smic my boost was all over the place, spikeing to 19 psi sometimes,lol, witch i dont know is safe on a smic,, now, i found the leak to be a split in a hose, ok, sorted that, so back to custom fmic, now boost is back to an indicated 15psi at the intake.... so why am i confused?, lol, well, would you say that my pressure drop is >4psi? now the confusing part is i thought id hook my boost gauge up to the n75 pressure in hose, pretty much strait off the turbo, and it still indicates the same sort of pressure, no more, and the gauge constantly sits 1psi with the engine off, but not when hooked up to the intake it sits at zero, now i presumed if i had a 4 psi pressure drop i should get 19psi on the gauge at turbo and 15 at the intake?, i know the gauge works ok when its running off the intake, iv ran upto 26psi at the intake on this gauge, so why would i see the same pressure at both ends???? this is why im confused, i dont want to run the fmic if i got a 4 psi pressure drop but would it be better than the smic, i also use mbc set to 22psi after the n75 to up my max boost, but i couldnt run 22psi on a smic could i??? its only a k0 turbo so i dont want to overspool it, iv been assured the compressor map says max 32 psi for these turbos so i want to keep it down so i can get a good intake pressure. any help with my confuseing sa here would be apopreiciated. this is making my head hurt, been worrying about it all day,lol. cheers

 

[ibizacupra]

if i read right then, you see 4psi pressure drop across your fmic, that you dont see on your stock smic.

sounds like a very poor flowing fmic core.. it might be cooling better, but flowing less, so for me thats a poor fmic

 

[bigboost]

aha, the man that knows..... well iwas thinking its a 4psi drop aswell, but im confused as to why im getting the same pressure at both ends? if its a loss, it from turbo to intake, from my signal in to n75 is where i put the gauge, so what ever n75 sees should show on my gauge, and i should add the extra 4psi was just a massive spike, then back to 15, now its just strait 15psi, no spikes, and with the mbc i can get it to hold til 5000rpm, my previous before the leak was 22psi holding 20 to 5000rpm then dropping strait to 10psi, now that was quite quick aswell, and was for atleast 3months,lol. now my main concern is heatsoak, so thats what puts me off going back to smic. with the side mount the car felt better off the line, but just died to quick for my likeing, even in the 3degree weather,lol, and i dont want just 15psi either, i got used to the second gear wheelspin at 20psi ;=p, anyway, if ive got a 4psi loss i know that its the pipes rather than the core as ive had to flatten a couple to fit, which i know is not ideal. but im stuck on what to do... do i keep the front mount thats been on my car nearly a year, looks phat, sound alot better, and makes the car fell better up top. or do i go low boost, side mount ic, slow car and no more woops thats too fast momnts,lol. what would be the best way to check the drop? go back to side mount, stabalise 15psi then put the fmic back on and see what pressure iv got?. thats the only way i can think to do it but its so much work... and iv already trimmed my new r32 bumper aswell;-[[[ .
advice is much appreciated, and sorry for my jumbled questions,lol, like i said, im confused,lol

 

[bigboost]

could it just be that the length and size of pipe has flattened the spike due to the distance the air has to go to reach the intake?

 

[ibizacupra]

its not easy to follow what you've type so appologies if I gte this wrong.
I dont think you have see a 4psi pressure drop, but a 4psi difference only due to overboost spike from different pipework setups.
what setup was it custom mapped for? fmic or smic

 

[bigboost]

lol, sorry mate forgive my typeing, im not used to posting in forums,lol.. thats what i was thinking was the pressure differance, as it just stops the spikeing. it was custom mapped for the fmic, and was set at 15 psi. but the guy knew i was running 19psi before the map with the mbc and a few other bits, so he set the parameters high or something, so i could raise the boost, iv had no feul cut yet and it has spiked 26psi at the intake a couple of times.
but yes, it was custom mapped with the fmic at 15psi, it is a little laggy blow2500rpm, but mbc solves that..
but another spanner in the works,, iv been offered to have my map redone,, thanks chipped uk,, at their hq in bromsgrove as i was saying i wanted the boost upped on the n75.
should i put back the smic and get them to map it with that or leave the fmic..

cheers for your help mate

 

[ibizacupra]

FMIC should work better, BUT so long as it genuinely does'nt restrict flow.
you should'nt have to run mbc, n75 should be faster acting than a bleed valve.

 

[bigboost]

yea, it does responde well when your moveing, the general spool up is abit laggyer but not dramaticlly, i only use the bleed valve to up my max boost till i can get to bromsgrove to get it re done for higher boost. thanks for your help and advise bill

 

[bigboost]

oh yea, i use a ball and spring valve not a bleed valve, after the n75, only for my max boost, any ideas how i can check if i have a flow restriction??