402 twin turbo mistake ?HELP!!!!
402 twin turbo mistake ?HELP!!!! Kinda long,bear with me ! Built a brand new LS2 stroker specifically for high boost/major power.Researched months and put together what I thought,was the perfect combo(for me anyway)Motor specs as follows,New LS2 block,stroker crank,compstar rods,diamond -25cc pistons,6.0 MLS head gaskets,ARP studs all around,stage 2 ,317 heads with new stainless/inconel valves,patriot gold springs/ti retainers,all the goodies.HS1.7 rockers,trickflow hardened pushrods,ATI superdampner,Comp XER cam232-228 585-595 on a 115lsa,Morel lifters.Fed by twin T3-T4 ball bearing turbos,FMIC,60lbs motrons,FAST rails,Aeromotive BR regulator,full return style fuel system with twin intank Walbro255s .In anticipation of all of this raw power I splurged on a Tex twin clutch setup,new slave cylinder,DTE trans brace,4 new tires,spare rear diff(just in case) Now for the fun ,right ? Not yet ! Car is not happy about all this new stuff,refuses to go into boost,infact,wont break the tires loose ! Runs smooth,up to transition,idles good,NO codes,1/2 lbs pressure in exh(no plugged cats) 15-17 in vacuum at idle,Fuel pressure good,rises under load,tune is rich,timing soft,but the damn thing will not boost ! Wife is real impressed,daughter beat me with her outback,any ideas ? Anybody ? Ran a smaller twin setup on my stock motor that killed this setup,build seems pretty run of the mill,perhaps not the hottest out there but should be reasonably strong ? Did get it to about 3lbs today,going uphill,then it blubbers/pukes falls over. Will NOT rev to 5K even downhill(well maybe if its steep)OK Gurus,step inside and point me in the right direction,ANY direction ! Thanks guys !
check your wastegate. When I first installed my incon setup, the previous owner had adjusted the wastegates to where they only put out 3 psi of boost. I gave them a few turns and it fixed my problem. I'm sure it's something simple for you also.
Setup with twin external wastegates.I removed one and checked,12 psi spring,fully shut,perhaps the other one ? tried running off the springs only,no difference.Checked the BOV,50mm Tial,shut,tight,not leaking,pulled tubes off inlet to intercooler and ran at idle,both turbos are pushing air(dont know if that helps but at least they are turning) Are external wastegates usually a problem ? Oh,and I am running stock knock sensors,C6,LS2 sensors seemed to be overly sensitive KR (maybe a clue ?) Timing is conservative,should not be that big of deal at 1-3 psi anyway,fresh fuel,no noise(pinging) I did remove the heads,no evidence of preignition/detonation,in fact pistons looked/felt fuel washed/rich/ able to wipe clean with a rag.Maybe another clue ?
Originally Posted by 2000TurboVert
Have you checked for any boost leaks.... In the exhaust, around the headers? Are you running a MAF, or SD tune?
if its real rich it will sputter and die. When I first got my turbo on my built motor the tune was PIG rich and at about 2-3# it would sputter and fall on its face. whats the AFR at transition?
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Originally Posted by highpockets
Car is not happy about all this new stuff,refuses to go into boost,infact,wont break the tires loose !
Also, where abouts are you from? We can't very well recommend someone close by to give you a hand if we don't know where you are.
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Originally Posted by ABeasst
if its real rich it will sputter and die. When I first got my turbo on my built motor the tune was PIG rich and at about 2-3# it would sputter and fall on its face. whats the AFR at transition?
Originally Posted by mdhmi
You are making zero lbs of boost? None regardless of gear or RPM?
Also, where abouts are you from? We can't very well recommend someone close by to give you a hand if we don't know where you are.
Also, where abouts are you from? We can't very well recommend someone close by to give you a hand if we don't know where you are.
Originally Posted by Pro Stock John
Where you located?
TECH Addict
Joined: Nov 2001
Posts: 2,659
Likes: 1
From: Bellevue, Wa
If you can get the car to Cali easy enough take it to Synergy.
They have done a large number of turbo cars there, I am sure it will leave there tip top.
Click the sponser link for contact info.
They have done a large number of turbo cars there, I am sure it will leave there tip top.
Click the sponser link for contact info.