dyno numbers--Suggestions??

[cola8d8]

Had the car dyno tested on a Dynojet today, I was a little disappointed (251hp/282 tq). I have a the X cam, TFS street heat intake, and AFR 165 heads. They guys at the shop told me I really needed the AFR 185 heads. Any one agree? Disagree? Suggestions? Air/fuel was good at just under 14 throughout the RPM range.

302
70 mm TB
24# injectors
70 mm MAF
1 5/8 eq length headers
X pipe no cats
MSD dist and 6AL
5 spd

 

[SMOKEDYA]

Um not sure what to tell you? Here is my dyno sheet with gt40p's crane cam 1.6 cobra rockers cobra intake l/t's and all the bolt on's? But for what you payed for your set up dont seem worth it? peace




View attachment 433220



john

 

[9 Deuce GT]

Those numbers are extremely low. I would suggest a compression test, or some other form of diagnostic check. If everything checks out okay, check the rocker setup. Are the pushrods the correct length, do they give the correct wear pattern on the valve stem tip? How did you install the cam? Was it degreed? What is your timing? Run codes on the engine with a code scanner. I would think you would be in the 280-290 RWHP figures at least, if not 300.

 

[r.barn5.0]

That is low.

I made 260rwhp with AFR 165's, stock cam, 1.7 RR's, and BBK intake.

with X cam you should be more than that for sure.
AFR 185's are waste for a 302ci, dont need 185's till you stroke it or blow it.

What is base timing at?
Was this a "Mustang Dyno"? cause they do read lower than a dynojet.

 

[Dark Knight]

He said dynojet
Did they do any tuning? another vote for timing change at least. My AFR's liked 17* initial..
Are you running the stock AFR valve springs? The X303 is close to the max lift on them..
Can you post the dyno sheet?

 

[DMAN302]

Definately something amiss...have you pulled the codes? My SCT tuner and I discussed the problems in tuning a car that was not in optimal running condition and how frustrated customers could get with the mediocre increases. Also the A/F is a bit lean, if there's too much timing in the curve you could be dropping power in the upper RPMs. What was your AVG HP and TQ?

 

[r.barn5.0]

one more thing

What spark plugs are you running?
I made the mistake of useing stock type spark plugs on my AFR's at first

They are not long enough and dont extend into the combustion
chamber, caused backfiring and lack of power.

Need to get the Autolight spark plugs. I forget the number, do a search

 

[stangjunkie]

numbers definatly seem low.... you really don't need 185 those are pretty big. your maf in a perfect world should be a bit bigger than th TB but thats not much if any of your problem.... did they just dyno or tune it?? sounds like you need a tune just to see what a great tuner can do

 

[cola8d8]

I dont have a scanner but I will take a pic of the dyno graph and try and post it. Thanks all for the input and I would appreciate more.

 

[cola8d8]

They did not do any dyno tuning (at my request, they offered). My timing was at 14 and the A/F was good so I spent the $65 for 2 pulls instead of the $150/hour for "dyno tune". With the disappointing numbers I choose not to spend the extxa $$$ for a "dyno tune" since the A/F ratio was where it should be.

Yes, stock AFR valve springs.

I dont have a scanner but I will take a pic of the graph and try to post it.

I appreaciate the suggestions/comments.

I will also check what plugs are in the car and post that info.

 

[DMAN302]

Trust me there's power to be had still in that combo..using a higher octane fuel allowed the tuner to be more aggressive with my timing curve and clean up the power curve quite a bit. I initially self tuned with 39psi of fuel and 16 degrees of timing. Power output on the initial pull was 276/300. We then burnt a 91 octane program it being a little more agressive netted 291/317. Next time out we burned the 94 octane program and again more aggressive curve and the addition of the taurus electric fan things got MUCH better....316/345. Tunes and handheld tuners are not cheap, but to optimize your engines performance the they can be very beneficial.

 

[N8Miller]

you would just waste time and money by going with 185s. if you did go 185s, you would prolly pickup 10-15, but then you would be disapointed by those numbers becasue you havent fixed your original problem.

 

[cola8d8]

here is a pic of the graph. The difference between the lower and the higher pull is taking out a pound of fuel pressure.

I always run 93 octane fuel also.
The ECC, MAF, and 24# injectors are all the ford cobra conversion kit also.

http://members.cox.net/cola8d8/DSC01258.JPG

 

[Dark Knight]

HP curve flattens out way to much at 4800rpm for the cam you have..

Here's mine with the stock cam and 165's

 

[Dark Knight]

Ok, this time it should work

 

[Threeo2]

looks like another mismatched combo to me. That cam and intake combo are doing nothing for ya, but you should still be making a little more power I would think. Maybe a bigger intake, like an rpm or track heat and reving the sucker to 6500?

 

[cola8d8]

What should the pushrod length be? This motor was purchased as an assembled long block from Central Coast Mustang so I assumed they would use the correct pushrods... BUT there was a problem, I ordered it with AFR 165s. They originally sent it to me with GT40 heads, they shipped me the correct heads the next day but did not send different pushrods. Should the pushrod length be the same for those two heads?

Plugs are Autolite 3924

 

[Dark Knight]

Length shouldnt be an issue between the 2 heads, unless one is pedestal and one is stud mount.
What rockers are you running? The reason I wonder about the valve springs is that the standard AFR springs are good to .550 lift and you're running .542. Pretty close... AFR says to use the upgraded spring package with hyd roller cams.

 

[cola8d8]

They are the stock AFR valve springs, maybe I need to change those....
I dont remember what rockers they are but they were blue.

Dark Night, do you think the stock AFR valve springs with that cam might be what is causing the low power and flat power curve? It is kind of a lot of work to change them but could get me on the right track.

 

[tmoss]

the shape of the troque curve is good - it's just way too low. Your not filling the cylinders well enough. Different cam and a slightly smaller cross section intake would help with that.