As background, I had the truck on a Dynojet a couple months back to get a tune from Sal. Hit a max power of 386HP, 450 TQ. I have a 4lb pulley, chip, filter, and thats about it.

This past weekend, I had a chance to put the new motor on the dyno. Same mods, but this time they were bolted to a REM-built long block with ported heads and crower cams. I was looking forward to seeing numbers, as this motor sounds MEAN

The first pulls were made on a diablo chip. It's purposely conservative so the low numbers werent too much of a surprise.


Then we did some tuning to the same autologic used with Sal. The new motor flows more air so we had to add some fuel. After about an hour, the chart below was the high pull.


Ok, so MANY thousands of dollars later I gained ... nothing? I know the shortblock is stouter which will allow me to mod higher in the future, but I was sorta surprised to get nothing out of the heads/cams but sound.

 

red X's

 

fixd

 

That sucks

 

wow, thats kinda screwed up bro, I might be kinda pissed there!

Sal was saying with his heads a modded L should pick up an easy 50 hp with cams and port work and I don't see why not!!!!

I guess now just bolt a KB on and boost the hell out of it.

 

Hey Nathan, first dyno was on a Dyno Jet and then on a Mustang Dyno. I have heard that the Mustang Dyno gives lower numbers than the Dyno Jet. Also you might look at the exhaust as the culprit for little gain in HP. With the heads flowing so good the stock exhaust could be causing restriction and hindering the heads you put on. A customer of mine just had his 03 Lightning with just over 500 miles on a Dyno Jet today and put down 395hp and 485ftlb's. All the parts were from REM and I put on FT valve body, complete exhaust with long tubes, Cobra R water pump, Flex-a-lite fan, 4# lower, Accufab TB, Cold air kit, Diablo Sport chip, and Denso IT22's. I have a set of ported heads and crower cams from REM that are going on my 01 next week. I expect some big gains from mine but my setup I will be running is a bit more radical.

Also why were the runs stopped so soon. Your power drops off around 5000rpm's on each run. The cams are designed to produce all the way to 6500rpm's. I would like to see a dyno pull all the way to 6500rpm's. Seems to me that there could still be some potential in the cams but the runs were to short?

 

Good question

While I wouldnt run any Mod motor to 6500, usually the HP peak is 4800 - 5000 and most runs I have seen the dyno chart has smooth degrading curve thru 5300 or so

Like this


LOWER Curve is HP
With the cams you may not have seen the peak by ending the run at 5000

 

Bingo! Mustang dynos are typically reported to read anywhere from 10-15% lower than Dynojets. At the high end of the range, that would equal 50% more HP.

Mustang dynos produce a "truer" number, but Dynojet numbers have become the de facto standard, so which is really "truer"?

Also, you simply can't compare numbers from different dynos, even if they are exactly the same model! Assume one is 5% low and another is 5% high. Instant 35 HP without spending a dime.

Gp back to the original dyno and rerun. I'll bet you will smile then.

 

Nathan's engine (i.e., the cams) does sound mean.

The Mustang dynos are great because of the ability to load the dyno (i.e., like driving down a track or on the street). Unfortunately, people are accustomed to seeing the "higher" numbers reported on Dynojets.

As for Nathan not continuing the dyno past 5,000 rpms, his engine had very, very limited miles, and I think he wanted to put some miles on the engine before pushing it hard.

It is also important to remeber that we are in San Antonio=HOT + HUMID! It was probably 90 degrees in the dyno shop.

Once Nathan puts some miles on his engine and puts on one of those spare tire size pulleys, he will post impressive numbers.

Greg

 

Funny, the crower cammed, porter head motors out here make easy power to 6500...Most only spin them to 6000 to help save on tranny life. Look at Dante's motor as a perfect example.

Different dyno's, different #'s. Your going to have to go back to the same dyno to see what your making.

I dont know which crower cams you went with or how wild the port job, but if you goto say 14-15 psi, you should easily be in the mid 450's-470's in hp with at least stage 2 cams.

 

you mean 5.4's i assume? my cobra was shifting at 7650 rpms

the mustang dyno will read lower, but i wouldn't count on 15%

in my experience on the tons of dyno's i was on was about 8%, it could be a bit more off, but firgure 8%. Lidio from alternative did a dyno test for 5.0 about 1.5 years back and that is the average from 2 dynojets to 2 mustang dyno's. so, add about 31rwhp which is about 40 crank and add about 36 ft/lbs which is about 50 crank

now, take it to the track, that will tell the tale!

 

Wow Doug your dyno numbers are very close to mine(see sig). We must have the same tuner

This was done on my street program.

 

The revs were kept down partly because the engine was new. But also because the HP started to plateau. I agree that the mustangs may read lower than a dynojet. However, I think that difference in this case was minimal. A friend with a 6lb lower and a stock motor put down 400/500 immediately after my pull.

I remember a while back people were saying that anything after the blower wont make power. In my case, that seems to be true.

 

What have Paul and Tim said concerning this?

WOT

 

This is a dyno of my truck on a mustang dynamometer at the beginning of the month. Air fuel was 10.0:1. I guess I'm at around 600 rwhp if they are of 10-15% lower than dyno jet...
stock cams.