95 Cobra Bolt-on Dyno results.

[Black95GTS]

Im still running the stock fpr on my car, and will continue to do so when I get my new #'s this spring, and they will be in the 550-565 rwhp range.

When I was doing a lot of research on fuel pressure regulators, I came across a lot of respected people indicating that when the the stock fuel pump is replaced with larger and more powerful tank and inline (or both) pumps, sometimes the stock regulator can't handle it and doesn't perform accurately. What I was trying to say is that you'd get the beefier aftermarket unit and set it to stock pressure.

Adam

 

[SVTtripleblack]

Thanks I really appreciate it. I just e-mailed it to you.

 

[SVTtripleblack]

Hey GMKILLER, I was wondering if you ran your car on a dynojet or mustang dyno when you got those 265hp and 309tq #'s? Not saying my #'s should be the same, but relatively close. My car has almost the same boltons that you did when you got those #'s. Do you still have the graph? How much timing were you running? Did you have it tuned at that point, or just that lucky?

 

[Venom351R]

 

[gmkillr]

Hey GMKILLER, I was wondering if you ran your car on a dynojet or mustang dyno when you got those 265hp and 309tq #'s? Not saying my #'s should be the same, but relatively close. My car has almost the same boltons that you did when you got those #'s. Do you still have the graph? How much timing were you running? Did you have it tuned at that point, or just that lucky?

That was on a dynojet.
16 degrees of timing, tuning was done on a Ford Extender.

 

[SVTtripleblack]

Thanks, I still think I'm going to have it tuned. Now that a good picture of the dyno is up, can anyone tell me if that A/F ratio looks ok?

 

[Methodical]

Here's an article on why an AFPR may not be a good investment for our cars. The short is the computer dials out any adjustments over time.


http://www.mustangworks.com/index.cfm/page_id/3/content_id/336

 

[5spd GT]

When I was doing a lot of research on fuel pressure regulators, I came across a lot of respected people indicating that when the the stock fuel pump is replaced with larger and more powerful tank and inline (or both) pumps, sometimes the stock regulator can't handle it and doesn't perform accurately. What I was trying to say is that you'd get the beefier aftermarket unit and set it to stock pressure.

Adam

That sounds like a wise investment for the price.

 

[SVTtripleblack]

I don't think I'm going to get an FP regulator. I just want the car to run safely and maybe pick up some power. I am pretty set on getting it tuned. I don't have any more money to sink into in for a while because I have a baby girl on the way and that's way more important. Can anyone please verify from my dynograph if the Air/Fuel ratio looks ok? It seems to be ok after 2500rpm, but I'm not sure what all the lines mean because there is no key.

 

[final5-0]

Thanks, I still think I'm going to have it tuned. Now that a good picture of the dyno is up, can anyone tell me if that A/F ratio looks ok?

Yes ... Its a bit lean ... but ... Not like you first indicated

I'd say around 12.5 to 13.0 to 1 for a ball park range

You just have to play with it and see what each combo likes

Grady

 

[final5-0]

I don't think I'm going to get an FP regulator. I just want the car to run safely and maybe pick up some power. I am pretty set on getting it tuned. I don't have any more money to sink into in for a while because I have a baby girl on the way and that's way more important. Can anyone please verify from my dynograph if the Air/Fuel ratio looks ok? It seems to be ok after 2500rpm, but I'm not sure what all the lines mean because there is no key.

That chart was done with equal scaling for hp & tq which I prefer

That means you can use left or right side values to determine hp or tq

Of course ... Across the bottom you see your rpm values

All you gotta do is just line up one side and bottom to see any particular
value of hp or tq at your chosen rpm

As for the fuel ratio

Same kinda deal

See that red dotted line ............
Look on the left to see it is sitting on the 12.5 to 1 mark

Notice how the hp, tq, and fuel ratio lines all quit at the same rpm

Hope that helps

Grady

 

[SVTtripleblack]

Yes it does, thanks Grady
The reason I said 14.0 to 1 right off the bat was because that's what the dyno guy told me before I even saw the graph. I guess it stuck in my head, and I wasn't completely sure about reading the graph to verify it. Do you think it's worth having it tuned?

 

[DDSTANG94]

Yes it does, thanks Grady
The reason I said 14.0 to 1 right off the bat was because that's what the dyno guy told me before I even saw the graph. I guess it stuck in my head, and I wasn't completely sure about reading the graph to verify it. Do you think it's worth having it tuned?

how does it run, any driveability issues?????

 

[SVTtripleblack]

It seems to run pretty decent. The idle will lope a tiny tiny bit once in a while, but never close to stalling out or falling below 650rpm. It does feel a bit slower to me lately, but maybe because I'm getting used to it. I know I would be spending at least $300 to get it tuned, I just don't know what I could gain from doing so. If I could pick up some power (10-15rwhp) and more high end torque I wouldn't hesitate to do it. Is that a realistic goal?

 

[final5-0]

I've been thinking about your Q's concerning getting a tune.

I just can't be certain about two things with you current combo.

That chip and meter. My greatest amount of suspect is the chip.

A stock Cobra has fairly fat WOT fuel tables and on top of all that
it has a fuel enrichment kinda thing going on starting at 90mph.

It looks as if your pull was stopped at 5700 so I can't be certain
but I'd think you went beyond 90mph with that kind of rpm. If
you look, you don't see any kind of dip in the curve toward the
end. Kinda makes me wonder

Your mods of tb, cai, shortys, or mid pipe, and catback shouldn't make
for lean conditions as I see it.

You might try pulling the chip and leaving that meter on to see how
it runs.

I honestly can't say for sure as I've never run a Cobra pcm with the
stock parts or just a few bolt ons similar to yours ... but ... It would
seem to me you would be showing fatter values at WOT.

As you said above ... that chip has changed the fuel and maybe it
has leaned it out too much.

Just thinking out loud here but with no way to verify .........
Trying a few things could not hurt is how I see it

Grady

 

[SVTtripleblack]

Thanks for all the input guys. I made an appointment for a tune over my lunch break. I know I probably won't pick up much power from it, but at least my car will be running right A/F and tuned for optimization. Since I already have the Diablosport chip I will be saving some money too. The guys at Don's Performance were really helpfull and said they can't imagine it taking more than 2 hrs to tune. They charge $150 for the first two hours, then $100 for each additional hour of tuning. Thanks again Grady and gang and thanks Redline 351R for getting a good copy of my dyno graph up.

 

[SVTtripleblack]

Oh Yeah, I'll let you guys know how I make out in about 2 weeks.