sideways500

right just had a hybrid t4 fitted to my rs500 to bring it back up to the original spec as it was runing a t34 also at the same time ive had a ported head fitted and a new custom exhaust fitted.
had the car in to be mapped today and the mapper says there no useable boost till over 6K comparin it to my t34 graph its over 100 bhp down at 4k this dosent seem right at all the first thing i fort it could be the garage that fitted the head have not timed it up right ??

any help or advice welcome cheeRS

MK5RST

Timing! , A mate of mines S2 was a tooth out and wouldnt come on boost till around 4k

Big Will_

Who's doing the mapping?

dave cos4x4

iTrader: (5)

surely the mapper could sort this.

cozbine

iTrader: (1)

Surely your mapper would have seen if the timings out

NEEDFORSPEED

hmm . . . . which mapper?

andrewg

sounds like the wastegate is not sealing right

i.ve seen the arms slightly bent and the disc doesn't sit square on the hole

andrewg

or preesure check the boost system for leaks

sideways500

mapper is my local omex mapper who mapped the car when the car was on the t34 he said he gunna have a play with the timing tomz and see if he can do any thing with it will also mention to him about pressure testing the system and the wastegae maybe not seating right

cheeRS

andrewg

i got an adaptor made that has various steps for all turbo dia's and a tyre valve on it and with an air line and a soapy water spray bottle ,you can soon spot the leaks that can cause lag that you never even knew about

jon@work

iTrader: (5)

dump valve diaphragm split perhaps ?

Rossco

Foookin good idea Andy

sideways500

spoke to the mapper this morning its not losing no boost and the wastegate is sealing ok , he said they t4s are laggy anyway but not this laggy, i had the head skimmed wen it was ported n polished and he reckons the timming was put on its original settings, so hes gonna tweek it on the verniers , but even then he reckons it wouldnt make a drastic diffrence?
so im still scratching my head

RobS

iTrader: (3)

hi mate did u get the t4 off me?

sideways500

yes m8 thats the one, its pretty much knackered can i have my money back?? please as you sold it as good

Ian M500COS

That turbo was originally on my car and used to start making decent boost at 3500rpm and was making 25psi at 4000rpm.

Who is the mapper???

sideways500

its with a company in cheltenham called MECH REPAIRS, and at the moment its making 12psi at 4k

Ian M500COS

What chip are you using and cams? Have they checked the cam timing. Does it have verniers?

I do agree that at 4000 rpm that it maybe should make a little more boost but by 4500rpm it should be pretty much on song!!

My experience with Mech Repairs and mapping was not a good one but well...... they should know Omex as they are just around the corner?

Any other ideas? Anyone?

Nash

iTrader: (3)

I have 22-23psi at 4100rpm with my T4, and full boost before 4500rpm.

Something defo isnt right there bud.

scoooby slayer

iTrader: (4)

as previous owner of turbo has said boosting at 4000 rpm i would say unlikely turbo and unlikely a leak either as would have to be a big leak to make that difference and you should clearly hear a leak of that size imo. pressure test inlet from intercooler inlet pipe to be sure and check timing, does the engine run as it should ?

sideways500

engine runs fine dosent sound out but im not a mechanic so i wouldnt know,
the cams are bd14 on the inlet and bd10 on the exhaust, i just wish there was someone i could just take the car to and say just sort it out and dont come back to me scratching your head saying i dont know why, th emap alone will cost me £500 and i havent gained nothing apart from a 500 that is vertualy undrivable, help!!!

Daviet

are msd able to map omex??would be my first phone call finding out if they do and if so when can i book it in

scoooby slayer

iTrader: (4)

tbh i suprised they mapped it like that they should of known there was something wrong and told you. as far as im aware once the problem is rectified it will need mapping again as fueling will be way to lean where you have no boost now but will have loads once its sorted if it was me id just take it to msd and let them sort it if your unsure of checking yourself. if the turbo is exactly the same on your car as it was on the previous owners car ie same actuator etc then its simply not getting the exhaust gas through it or its got a massive leak. only inspect hoses etc that have changed with the turbo change as everything was obviously alright before.

Deleted by Request

...something aint right...i had a t4 on std cam timing with bd10's and it was at full boost by 4500rpm on a mild ported head!

scoooby slayer

iTrader: (4)

deffo mate my head is only mild and had to be capped to 25 psi to 5000 rpm then 32 psi to 8000 rpm. i cant believe they mapped it like it very poor service imo.

Deleted by Request

..same as my conversion mate..25psi max till higher up....my later conversion had a grp a head with bd16 in and bd14 out which gave me 32psi from around 4300rpm till 8000rpm

sideways500

well i dont know anywhere else that can map omex ecus and i have tryed. wheres is msd anyone got a contact number for them ?

Daviet

http://www.motorsport-developments.c...s/whoarewe.htm

sideways500

thanks unfortunateley he cant fit me in until january, hopefully my mapper will sort out the problem as it is his job, still havent a clue thou

philram

iTrader: (3)

try fitting a set of standard cam pullys and see if that helps, should show if its a cam timing issue... i had the same with my t34 and it worked, also has the actuator gone weak, and is letting the wastgate open.?

sideways500

well after another mapping session im still no further forward, the timming was slightly out but this hasnt made no diffrence, still only 10-12 psi at 4k , there are no leaks and the mapper hasnt got a clue!!!! the actuator is working fine and the (penny is sealing good)
anybody got any ideas???
looks like im gonna have to pay them and take the car elsewhere i hate wasting money
can believe my luck it starts boosting hard at 6k and hits the limmiter hard
looks like it will have to go to msd after crimbo

mechanic28

iTrader: (5)

strange what exhaust u got fitted,poss something wrong with it stopping the gases flow probably at lower rpm thus effecting the spool of the turbo??

sideways500

had a new custom exhaust fitted non resinated and honed out for more flow around the weld lines so it would flow better
im thinking that there must be something wrong with the turbo itself as there cannot be nothing else ???
the previous owner has said it has had a a bit
of fettling by universal turbo, ie wastegate penny honned out a bit??i believe may be its not sealing properley?

mechanic28

iTrader: (5)

do u still have your T34?

sideways500

yes i think im going to stick it on and see if eveything is ok so then this will rule out any other problems apart from the t4 being faulty

mechanic28

iTrader: (5)

yer that is what i was going to say

sideways500

well we found out what the problem is looks like the penny isnt sealing properley, causing it to lose boost so the turbo gonna have to be looked at,
thanks everyone for your help and advise the mapper hasnt charged me and has given me good advise and will continue with the map when the turbo is fixed

OvaBoost

Alright lee it's matty - you gonna take me up the road in it when its done then or what haha

mappindude

I am Dave from Mech Motorsport (the mapper)

I want to clear a few things up.
Firstly I havent charged the customer a penny as yet (let alone the £500 already mentioned.)
secondly I havent at any stage fully mapped the car yet.!
Cam timing Is not a quick visual check on a car with modded crank pulley and vernier wheels!.It is with std wheels!
The problem is the penny on the waste gate. It is a floppy fit on the wastegate arm and was causing the penny to stick open solidly at various postions . (the actuator spring couldnt pull it back)
It was intially set at one of these seized positions so it was always slightly open.After fiddling and moving the penny arm back and forth it suddenly shut another 9mm!! and the actuator arm suddenly had no preload.
Will fully map when turbo is fixed.
Hope this clarifies everything.

mechanic28

iTrader: (5)

nice user name,welcome to pf chap