boost problems.....help...

modified man · 14-08-2009, 08:23 AM

hi all ...got a question for yas.....friend has a supercharger (rotex) on an m3 but for some reason it drops boost at high revs (around 7500/8000 rmp) its got nos and also a meth kit on it ...we've checked elec..not that.. checked vac lines..not that..he hit 573 rwhp..before motor rebuild (lifting the head).... only just got good dyno readings yesterday (611 rwhp) and should get 650+ once the prob is sorted but we are starting to pull our hair out trying to fiqure out the prob is.. but its a massive boost drop....any suggstions....we've also looked at the blower internals real minor wear on the blades but nothig to be concerned about....ill try and organise some pics of it to .............thanks..

blwnlj · 14-08-2009, 10:33 PM

Heard of a similar problem a while back on a blown holden stroker,ended up a valve spring problem (weak)even though they were good quality they had gone off over time.Maybe its dumping boost out the exhaust

modified man · 15-08-2009, 10:09 AM

yeah dont think it would be valve springs ..the motor is only about 2mths old and the bet sh.t was bought, but then stranger things have happened i guess so ill pass it on and we can check it out thanks.........anyone else got any thoughts on this prob

vl1271 · 16-08-2009, 04:13 PM

is the blower to small and not keeping up with the motor

modified man · 16-08-2009, 05:36 PM

nah mate the blowers ok ..getting a bit tired though its done around 300 dyno runs.... the guy who owns it is doing all the pioneering work for active auto works in the states.... they just released an up grade for it but no point changing it till we sort this prob out....and it wasnt the valves ...said the computer would have told him theres a prob their....he loads his own maps etc so anything goes wrong the pc usualy tells him what going on.........he has this neat little nos controler for it that he dials in how much nos he wants and when he wants ....the fast and the furious style sh.t good fun......should be working on it again soon so ill let yas know how we get on..........

baconson · 03-02-2010, 01:23 PM

how does the laptop tell him the condition of the valve springs?
and also what model blower and how much is he trying to squeaze out of it

14-08-2009, 08:23 AM	#1 (permalink)
modified man Newby Join Date: Aug 2009 Location: brisbane Ride: n/a View My Photo Gallery Posts: 46	boost problems.....help... hi all ...got a question for yas.....friend has a supercharger (rotex) on an m3 but for some reason it drops boost at high revs (around 7500/8000 rmp) its got nos and also a meth kit on it ...we've checked elec..not that.. checked vac lines..not that..he hit 573 rwhp..before motor rebuild (lifting the head).... only just got good dyno readings yesterday (611 rwhp) and should get 650+ once the prob is sorted but we are starting to pull our hair out trying to fiqure out the prob is.. but its a massive boost drop....any suggstions....we've also looked at the blower internals real minor wear on the blades but nothig to be concerned about....ill try and organise some pics of it to .............thanks..

14-08-2009, 10:33 PM	#2 (permalink)
blwnlj Learner Driver Join Date: Dec 2008 Location: Ballarat Ride: LJ Torana, VZ 6Lt Crewman, Daihatsu feroza,XH ute View My Photo Gallery Posts: 341	Heard of a similar problem a while back on a blown holden stroker,ended up a valve spring problem (weak)even though they were good quality they had gone off over time.Maybe its dumping boost out the exhaust __________________ WHERE THERE'S SMOKE THERE'S TYRE To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

16-08-2009, 04:13 PM	#4 (permalink)
vl1271 Gear Cruncher Join Date: Mar 2008 Location: junee nsw Ride: blown vl commodore View My Photo Gallery Posts: 238	is the blower to small and not keeping up with the motor __________________ 12/71 blown!!

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15-08-2009, 10:09 AM	#3 (permalink)
modified man Newby Join Date: Aug 2009 Location: brisbane Ride: n/a View My Photo Gallery Posts: 46	yeah dont think it would be valve springs ..the motor is only about 2mths old and the bet sh.t was bought, but then stranger things have happened i guess so ill pass it on and we can check it out thanks.........anyone else got any thoughts on this prob

16-08-2009, 05:36 PM	#5 (permalink)
modified man Newby Join Date: Aug 2009 Location: brisbane Ride: n/a View My Photo Gallery Posts: 46	nah mate the blowers ok ..getting a bit tired though its done around 300 dyno runs.... the guy who owns it is doing all the pioneering work for active auto works in the states.... they just released an up grade for it but no point changing it till we sort this prob out....and it wasnt the valves ...said the computer would have told him theres a prob their....he loads his own maps etc so anything goes wrong the pc usualy tells him what going on.........he has this neat little nos controler for it that he dials in how much nos he wants and when he wants ....the fast and the furious style sh.t good fun......should be working on it again soon so ill let yas know how we get on..........

03-02-2010, 01:23 PM	#6 (permalink)
baconson Newby Join Date: Feb 2010 Location: Queanbeyan NSW Ride: 2009 buell XB12ss, 1988 mazda 323gtx turbo, 14psi, wrx cooler, microtech lt4, HEI Posts: 9	how does the laptop tell him the condition of the valve springs? and also what model blower and how much is he trying to squeaze out of it