bad dyno numbers.....
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yellow5.0cobra said:it doesnt matter if the compression was that low, it will still have spunk and wouldnt lose 40hp.
210* wont ROB power, but its not the best constant temp.
If the computer threw a code, it would be in LIMP mode, aka, RICH condition.
You should be EASY in the 320rwhp mark, IF not a little more.(with a 5spd)
exhaust leaks DONT help, so fix those ASAP.
No pun intended here, I know your a moderator at BOOST & NITROUS, but I have to say you are wrong about temperature, even 210º robbing power. I know for a fact that a car that is running 210º will not make as much power as a car that is at 180º or a little below. I have tested this many times at the track ( note: probably 40+ times ) and the hotter the motor got, the slower mph the car went. ( mph representing horsepower the car is making ) Granted I only lost about 1- 1.5 mph when I didn't let the car cool, but it is still losing power. IE: One run I started the run at 205º and ended at 215º on the temp guage. The car went [email protected] run w/ nearly the same 60' time, the car was cooled down to 175º on the temp guage, and went [email protected] is just ONE example, but I have done this many times and noticed a different..Hence, the use of ice on intake manifolds..etc.
Also, I don't see the point in having a 30# injector for 300rwhp?? N/A a 24# injector will be good up to around 400hp, and a 30# injector up to a little over 500. This is according to chart given by pro-flow.com : http://www.pro-flow.com/tech info/sizing.htm I don't think I would personally use a 30# injector at 400hp, as its duty cycle would be nearly maxed, if not maxed, but the chart given on the link above should give a good estimate of injector vs hp.
IF this is useless information, excuse me for contributing, but I do believe the statements that I have provided are accurate.
Dan
DMAN302
My mom says thanks for the pearl necklace.
You should be looking for vacleak, it could be playing havoc with your fuel and timing curve. Many others have an opionion here but the rising RPM when clutch is engaged is sign of vac leak and if you start with the obvious it's easier to problem solve.
yellow5.0cobra
Founding Member
see, i dont see 1mph as a big loss, i am not a HARDCORE money racer, therefor it does not bother me.
we can lose 1mph just by doing the most simplest goof up in the cockpit.
I do recommend a working temp of 200*, and I do recommend BLOCKING the EGR.
The EGR does nothing but makes the incomming air HOTTER...
imagine cool air hitting a piece of aluminum 120*+? the molecules just SCRAMBLE.
we can lose 1mph just by doing the most simplest goof up in the cockpit.
I do recommend a working temp of 200*, and I do recommend BLOCKING the EGR.
The EGR does nothing but makes the incomming air HOTTER...
imagine cool air hitting a piece of aluminum 120*+? the molecules just SCRAMBLE.
blown5.0
Founding Member
problem is simple:
1. your cam is too small for the heads and intake. a compcams extreme energy with a .050" duration around 230/236 would make tons more power.
2. your 12.5:1 a/f ratio is rich for a n/a motor, dial back the fuel pressure until you get around 13.5:1
doing these two things I can see putting down 325rwhp/325rwtq
and for a side note the eec-iv's use the o2 sensors and mass air sensor to keep a set a/f ratio as it is programed for at part throttle. at wide open throttle the computer ignores the mass air sensor and 02 sensors and uses a lookup table for a set injector pulse width at a given rpm, so injector size and fuel pressure is critical on these cars for a good a/f ratio.
my setup is a 302, ported tw heads, extreme energy custom cam, rpm air gap intake, full exhaust and a 650carb and it puts down 363rwhp at 5900 and 328rwtq at 5200.
1. your cam is too small for the heads and intake. a compcams extreme energy with a .050" duration around 230/236 would make tons more power.
2. your 12.5:1 a/f ratio is rich for a n/a motor, dial back the fuel pressure until you get around 13.5:1
doing these two things I can see putting down 325rwhp/325rwtq
and for a side note the eec-iv's use the o2 sensors and mass air sensor to keep a set a/f ratio as it is programed for at part throttle. at wide open throttle the computer ignores the mass air sensor and 02 sensors and uses a lookup table for a set injector pulse width at a given rpm, so injector size and fuel pressure is critical on these cars for a good a/f ratio.
my setup is a 302, ported tw heads, extreme energy custom cam, rpm air gap intake, full exhaust and a 650carb and it puts down 363rwhp at 5900 and 328rwtq at 5200.
86Cobra
Founding Member
blown5.0
Founding Member
at a certain throttle position the eec goes into WOT and at this point the older eec uses a lookup table for injector pulse with, which is why you can tune the a/f ratio via fuel pressure or injector size, on the never eec's they are always using feedback to maintain a certain a/f ratio at these require a chip to set the new a/f curves. My point being on older eec cars the injector choice is critical to good power, slapping 30# injectors on a stock motor will run good at part throttle as long as the mass air is cal'd right, but at WOT it will run way rich.
86Cobra
Founding Member
blown5.0 said:
I don't know where you get your info, but all Mustang mass air EECs use the meter at wot.
blown5.0 said:
Wrong. WOT is the easiest to get right with a cal'd mass aior meter. Idle and part throttle are much more difficult because you're metering a much smaller amount of fuel.
oz
Founding Member
I don't want to step into that argument...
My comment would be that once you get your vacuum leak fixed (assuming you have one), I would certainly think your combo (as is) should make more power than that. I would guess 300, 320.... It really should do better than my combo - with the E7's and all... Your torque is really low and I blame that on the big heads.
My car will idle at 750 all day once it is warmed up - I needed a chip for it to do this though...
If your heads are too big (which I think they are for your cam), the low end will suffer greatly. If the cam is too small (which it is for your heads), high end will suffer.... Unfortunately, you have the worst case scenario - your low end air flow velocity is so low that you don't make any torque and your cam is so small that you can't get enough flow at high rpms.
Ditch the cam and get something bigger.... just be sure that you will have enough piston to valve clearance. If you do this, I would bet you would see 340, 340.
If you don't have a chip, get one.
A note on fuel pressure - pressure and fuel volume are not a direct relationship - the fuel flow increase will be the SQUARE ROOT of the pressure difference.... increasing pressure from 40 to 50 psi only changes the flow by about 10%...
No offense to anyone but this is a lesson that part combination is critical.
My comment would be that once you get your vacuum leak fixed (assuming you have one), I would certainly think your combo (as is) should make more power than that. I would guess 300, 320.... It really should do better than my combo - with the E7's and all... Your torque is really low and I blame that on the big heads.
My car will idle at 750 all day once it is warmed up - I needed a chip for it to do this though...
If your heads are too big (which I think they are for your cam), the low end will suffer greatly. If the cam is too small (which it is for your heads), high end will suffer.... Unfortunately, you have the worst case scenario - your low end air flow velocity is so low that you don't make any torque and your cam is so small that you can't get enough flow at high rpms.
Ditch the cam and get something bigger.... just be sure that you will have enough piston to valve clearance. If you do this, I would bet you would see 340, 340.
If you don't have a chip, get one.
A note on fuel pressure - pressure and fuel volume are not a direct relationship - the fuel flow increase will be the SQUARE ROOT of the pressure difference.... increasing pressure from 40 to 50 psi only changes the flow by about 10%...
No offense to anyone but this is a lesson that part combination is critical.
blown5.0
Founding Member
no arguements here. 
I stand corrected on the mass air thing.
qouted from an eec-iv book:
"While in closed-loop (part-throttle) operation, the EEC uses feedback from the car's oxygen sensors to monitor and maintain a "stoichiometric" air/fuel ratio. This ratio of around 14.7 parts air to 1 part fuel is that which produces the most thorough combustion. At wide-open throttle, or in open-loop, feedback from the O2 sensors is ignored and A/F is dictated strictly by the EEC."
my point being is that at part throttle or closed loop with the eec-iv's you cannot control the air fuel ratio due to the feedback from closed loop (unless its reprogramed), where as at WOT its in open loop and you can tweak the fuel pressure to dial in the a/f ratio. The direct way is via injector size, fuel pressure or injector pulsewidth.
I stand corrected on the mass air thing.
qouted from an eec-iv book:
"While in closed-loop (part-throttle) operation, the EEC uses feedback from the car's oxygen sensors to monitor and maintain a "stoichiometric" air/fuel ratio. This ratio of around 14.7 parts air to 1 part fuel is that which produces the most thorough combustion. At wide-open throttle, or in open-loop, feedback from the O2 sensors is ignored and A/F is dictated strictly by the EEC."
my point being is that at part throttle or closed loop with the eec-iv's you cannot control the air fuel ratio due to the feedback from closed loop (unless its reprogramed), where as at WOT its in open loop and you can tweak the fuel pressure to dial in the a/f ratio. The direct way is via injector size, fuel pressure or injector pulsewidth.
