ramtd02

Well hit 3 dynos today, could not seem too keep traction on any of them (mustangs). Every run I tried, as soon as the fuel hit hard (2100), the HP and tq curve dropped straight down, and stayed there, plus i was at 3000 rpm which should be 85 mph, but i was still only doing 58 according too the dyno!!

Best I saw at 2000 rpm was 1345 for tq, and hp @ 2000 was 559. Anyone guess what hp would have been at 3000??

Managed too get 1, 1/2 throttle run....any more and the tires would slip. Even tried dropping tire pressure too 5 psi, strapping it down and then loading the tires upto 45 psi. Still no go!!! But I have a comparison of rail pressures between Beat smarty, dr.p predator, and stock.


Smarty Beta: Idle: 9000, Cruise @ 65mph: 17000, WOT @3200: 22500
Dr.p: Idle: 6500, Cruise @ 65mph: 20000, WOT @ 3200: 24500
Stock Prog.: Idle 6000, Cruise @ 65mph: 14000, WOT @ 3200: 22000.

So when Bob and Marco say they add a "touch of pressure", they aren't kidding. Only 1000 psi more at WOT, 3000 more cruising, but stragely 3000 more @ idle....not sure why this is, but I can tell ya that the engine sounds normal.

Hopefully I can hit a dynojet, maybe actually keep traction.

abc4yew

How much nox were you spraying....Take a look at some dyno graphs and you will find that HP doesn't get more than 20% higher as RPM's go up and alot of programs drop hard after 2900. The torque number looks good...if you calculate your HP number off this you should have something close to 650 which is great for a little turbo...the Nox might get you something beyond 2900....Take a look at an RCox dyno....yes near double the hp but spraying.

I had the same trouble last year....truck says 80mph...dyno says 60mph... I couldn't get above 550hp on the dyno consistently and both my curves were heading vertical. Soft compound tires with 3 straps front and rear of axle to grippy drum with the deflate and inflate helps. The secret is to keep your torque and HP rise linear and not too steep. When my twins lit it was 15 to 90psi in under 2 seconds then down to 30psi. If you can control your boost and fueling you can lay it down....Had the same problem on the track. Pressure is not bad....Rail Pressure high rate of increase is the problem...If you go from 6kpsi to 28kpsi in 1 second you will do more damage than 9k to 25k in 1.5seconds for example. The Smarty keeps the idle rail pressure high to allow for instant acceleration. ks

973604x4

Good info on the rail pressure.....mine is 26500 stock! (modded pump)

ramtd02

no NOX during the run....

This is with a modded pump!

morkable

Which dynos did you try Jon?

Kevin

jlibert

thanks for sharing your results. Are the pressures posted during WOT runs the max or minimum pressures. I see a lot higher pressures with my beta 4.4 maxed out at like 27k. Drops to about 21.5 wot.

wap

Good information

jrussell

So your II modded pump isn't able to keep up with your 90hp injectors?

MikeyB

Gee, 9k psi at idle. No wonder the beta 4.4 pulls so hard right off idle.

MikeyB

jlibert

Went to the beta program and everything changed. Still trying to figure out if I'm down on power from the previous wild program, or if the beta program ramps the power up enough to fix the previous loss of RP issues. I can tune it to smarty 8, tst 2/1. Any higer on the TST and rp falls off to 16k or so.

ramtd02

GCL, Subracing, and Campbell's....barry was saying the only chance i have of hooking up is on either a dyo-jet or water-jet....simply due too the better surfacing on these dynos and lack of load.

Those are what i see @ WOT, every program i have will spike too 27.5+K with either a throttle let off, or the initial jump....these pressures are steadied out, no bouncing around, just steady state.

I know your quoting someone else....but my II pump easily keeps up with my injectors which are 90's, but were customed too 110ish.

ramtd02

Your guess of 650ish sounds good too me, that is kinda what i figured looking at the graph, and then after trying don m's calculations, came up with 657 hp with my trap speed and weight. 650 on #2 sounds good enough for now.

jrussell

So does yours also drop to 21.5k at WOT?

ramtd02

no, if i am cruising, and decide too jump on it, the WORST that happens is the pressure will go from where it was (17k), then jump too 23-24, then steady out at 22.5K, My rail pressure never "falls off", it usually just ramps up to were it needs too....

morkable

What tires you running? I noticed that was a big problem on the dyno was the brand of tires. The guys with BFG couldnt hook to save their souls, my falkens hooked up real nice,, I am hoping that they will hold good on the track too

kevin