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My POS...any ideas?

boostedmach

Well-Known Member
So my car has been on and off the dyno...ALOT We got alot of things figured out, previous problems, but now, when its time to tune and make some power... The car is having some big problems. (This has been going on for awhile I think, first time the car has really been setup right)

Setup
2004 Mach1
Forged Rods/Pistons -16cc Dished
Procharger D1 3.4" pulley with 10% OD crank
Twin Focus Pumps in Cobra Tank, Stage2 FPDM
PMAS MAF in VMP's 80MM housing (blow through)
WeaponX Coils
NGK TR6 Plugs gapped to .31-.32
STOCK Heads, Cams, Springs

Take a look at the HP and TRQ curve..its crazy What do you think would be causing this? I have the datalog info if any can view it I would be glad to upload it.


Any one have any ideas?
chrisholmescrappy.jpg
 

boostedmach

Well-Known Member
I thought it was good up to a certain RPM and then it would happen?

We seem to have fixed that problem, with it looking all crazy...but this roller coaster of a curve...has been there for awhile...

Thinking it might be these damn WeaponX Coils, Dante says it looks almost like im floating my valves, but..I got stock cams...so thats almost impossible.
 

02gt

Well-Known Member
mine looked like that but thats because of the meth....i'd say your valves are floating too, bobby's car was doing the same too a few months back....
 

boostedmach

Well-Known Member
mine looked like that but thats because of the meth....i'd say your valves are floating too, bobby's car was doing the same too a few months back....

I have stock Heads/Cams with 40K miles....this does not make sense.
 

yosemiddysam

Well-Known Member
Donator
Ya know as much as I hate to say this I have to let my OPPINION heard........ Take your car to a different tuner!!!!!!!!!! See if they can figure it out! If not then I bite my tongue...... I bet I dont!!!!!

Emillio if this is bad then erase it!!!!
 
I

Ichiduo

Guest
Ya know as much as I hate to say this I have to let my OPPINION heard........ Take your car to a different tuner!!!!!!!!!! See if they can figure it out! If not then I bite my tongue...... I bet I dont!!!!!

Emillio if this is bad then erase it!!!!

patient - doc... it hurts when i touch my leg here... ow... here... ow... and here... ow... the last physician said i could have some nerve damage...

doctor - lemme see your finger... does this hurt?

patient - YE-AHHHHHHH!!!!!

doctor - i think you have a broken finger and nothing is wrong with your leg.

second opinions are always helpful... :)
 

4CEFED

Well-Known Member
+1 on floating the valves, when boosting you should always get aftermarket springs just to be safe.
 

yosemiddysam

Well-Known Member
Donator
I dont have aftermarket springs......... I have 15 pounds of boost on a 8 lb build!!!!!! Take your car to a place well known in Downey, and your car will be right!!!!!!!!!!!!
 

orange395w

OG MEMBER
Staff member
Has anyone been monitoring fuel pressure during the run? What size feed line are you using?

Just because you have a stock cam and springs doesn't mean valve float is impossible. Stock springs weren't designed for 17lbs of boost. I wouldn't jump to this conclusion just yet though. You need to look at Fuel and Ignition related stuff first.
 

orange395w

OG MEMBER
Staff member
Vacuum leaks???? What has been checked on this car? It looks like alot of parts swapping to troubleshoot vs actually troubleshooting. Parts swapping to troubleshoot is o.k. if the parts are free, but when they are not, well.......ya know the rest.
 

boostedmach

Well-Known Member
Fuel pressure Was data logged, was between 38-43 rail pressure the whole run. Stock Fuel line.

Dante checkd the vacume lines, and harness for any breaks or somthing chewed up.

Tomorrow, Im pulling the Coils, checking plugs, Checking the Maf, Checking Fuel Filter, Going over the car front to back to check everything. Also Think im going to replace the coils with the stockers.
 

boostedmach

Well-Known Member
For anyone who knows what they are looking at. It looks good on the datalog, but the dyno tells another story

Capture-1.jpg



-boosted
 

orange395w

OG MEMBER
Staff member
Fuel pressure Was data logged, was between 38-43 rail pressure the whole run. Stock Fuel line.

Dante checkd the vacume lines, and harness for any breaks or somthing chewed up.

Tomorrow, Im pulling the Coils, checking plugs, Checking the Maf, Checking Fuel Filter, Going over the car front to back to check everything. Also Think im going to replace the coils with the stockers.


Why is your fuel pressure not increasing as boost rises? I can't imagine that running 2 pumps & shooting for 600+hp through a dinky stock line is adequate. I'm not an expert on the mod motor stuff, but these are the things that stick out to me.
 

SCJ

Well-Known Member
My next door neighbor (literally), owns the DYNO SHOP in Santee. He is very good at what he does, certainly one of the best, and would be a great resource. One of these days my GT500 will hit hit his dyno and get a good tune. He is a great guy, that I feel like I abuse too much. Always asking for help from him, but i'm trying to be better and not take advantage of his knowledge all the time that he s freely gives and gives. Certainly worth the good second opinion. I don't know who Dante is but I would give the DYNO SHOP a call.
 

Lordgufi

Well-Known Member
honestly what it looks like to me is a fuel problem... check your regulator and ensure the damn thing isn't stuck.

the one on my talon got stuck and gave me all sorts of hell under pressure.

38-43 is a HUGE fluctuation in psi. i mean hell 2 psi is enough to cause a lean/rich condition

+ the size of the injectors your running with that much fluctuation is only compounding the problem.

IMO check the regulator if it hasn't already been done.
 

boostedmach

Well-Known Member
Why is your fuel pressure not increasing as boost rises? I can't imagine that running 2 pumps & shooting for 600+hp through a dinky stock line is adequate. I'm not an expert on the mod motor stuff, but these are the things that stick out to me.

I dont know, I'll talk to dante about it. But from what I have gathered, Staying at a target fuel pressure if what the returnless systems try to achieve, By raising fuel pump voltage to keep up with the injectors. Cause I mean, in the perfect world, If you could keep your rail pressure at lets say 48lbs where your injectors are rated for...through out your run would be ideal.
 
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