Just got back from the Dyno

HoofnIt

Founding Member
Jan 8, 2001
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36
North Carolina
I learned alot today and although I didn't quite reach the 300rwhp mark I am still happy with the outcome and my ping is GONE! The car also feels alot smoother and the fan temps were lowered.

stock, untuned 278hp 317tq
after tuning 283hp 316tq
minus Flowmasters 291hp 323tq

Bottom line the car did not perform better by adding more timing in the upper rpms. The power/torque curve pretty much peaks at 5000 and 4100 rpm respectively. My valvetrain was floating at 5800rpm but I think I need to readjust the valves and use 3/4 turn as opposed to 1/2 past zero lash. The tuner seems to think my Cobra intake (ported lower) is holding the power down. I'm pretty much falling off @ 5600rpms. Even with a different intake I guess the point would be mute without upgrading the valvetrain.

If anyone wants to comment I would appreciate it. I would post the graphs but they are a winPEP 7 file.

Thanks!

I found it very interesting that with the Flowmaster 2 chambers disconnected the car picked up 8 rwhp. Although I did not reach my goal of 300hp I came pretty darn close and the ULTIMATE goal is to attain high 12's at the track and with this data I know the numbers are there, now I will need alot of practice.
 
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Who ever said you need backpressure?!

Have you ever seen inside of a Flowmaster muffler? If you have, you would know why they kill horsepower. It looks like Flowmaster welded metal bricks in the muffler...

Those are very impressive numbers for such a "small" cam.

Joe
 
Damn nice numbers indeed. I wonder how much my stock tail pipes are hurting me... if I showed you pics of how they are butchered on there and how much of a restriction there is I think you'd crap. Hopefully I can address that issue soon. Again, congrats! Did you make peak HP at 5000rpms???
 
Peak torque occured around 4000 to 4100 rpm. Yes, peak hp was @ 5000 rpm and started to fall off 5600-5700. I don't know how to post the graphs. I should be able to take a pic of the printed version if all else fails.
Does anyone know of some quality cut-outs? I'd love to be able to crawl under the sides of the car and turn a valve when I'm on the track but I want a good seal and no leaks.

I won't be able to take it to the track for another 3 months! :mad: I guess that will give me some time to get some drag radials.
 
I wanted to ask about your valves floating. It would seem to me that the
springs are quite not up to the task of controling the valves. I don't think a little less preload on the lifters would make a difference.

Are you using the regular AFR springs or the upgraded ones?

I've seen many folks get pretty good results with that cam.

Later
Grady
 
Grady, the preload may not be affecting the valve floating but they are a little too noisy. The springs are not the upgraded versions. However, I am using 1.7 rockers. From the graphs it doesn't appear to be making much power past 5500 rpms so I don't see a need to run it past 57 or 5800 when I go to the track.
 
Please don't look at a new intake until you get the valve train fixed - that could be holding the power down, not the intake. If it was ported correctly, it will make a lot of power. Here is the dyno results of one of my recent customers who went to a RPMII and lost lots of troque and power under 5,200 rpm compared to his ported Explorer.........
 
tmoss said:
Please don't look at a new intake until you get the valve train fixed - that could be holding the power down, not the intake. If it was ported correctly, it will make a lot of power. Here is the dyno results of one of my recent customers who went to a RPMII and lost lots of troque and power under 5,200 rpm compared to his ported Explorer.........



Hmmm... I wonder which one I'd rather have and which one would be quicker. :D HINT HINT... it's not the RPM II! Thus another example of "bigger isn't always better."
 
I agree with the guys on the valvetrain; Grady especially.

120# on the seat is not nearly enough pressure, and I'd imagine that the open pressure is in the 330-340# range. Just as a reference, my springs at 142# on the seat and 405# open. The springs aren't up to it. I hope for your sake that it is just a lifter preload issue, but I don't see that being the problem

Paul, I NEVER knew you were still running the stock AFR springs! Maybe AFR used to use a beefier spring "back in the day" when their SBF market wasn't so big? That's incredible, but kind of scary at the same time.

Joe
 
A thought or maybe it is a Q, it don't matter. Paul says he has same springs as HoofnIt and has no valve float plus higher rpms.

HoofnIt is using 1.7 rr's. I don't think Paul is and that extra lift just might be the difference that is causing the float.

Later
Grady
 
As to losing power after 5000rpm, are your distributor & coil stock? If so, you may want to upgrade them. My stock V8 felt like it was losing some power around the 5000rpm range, just before my pig-of-a-AODE would upshift. I added a Performance Distributors dizzy and coil, and the car now pulls hard until my AODE upshifts. Granted, this is a seat-of-the-pants feeling, and not backed up with dyno numbers. But I think it's worth looking into.