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Sleepy4.7 on the dyno again.......

4K views 20 replies 8 participants last post by  FlyinRyan 
#1 ·
Welp, at the last minute I opted in for a Dyno Day at Slowboy Performance in Debary, FL.

My combo is as follows:
FRP 4" insulated intake w/ 6x11" UNI foam filter
FRP 4.7 TB (ported, no polish) w/ port-matching to 08 manifold adapters
Air Ram 08 manifold adapters w/ FRP porting + mirror polishing
VHT-coated 08 manifold
SCT 93 octane custom tune by Sean Powell/KRC Performance
Metallic cats
3" Y-back exhaust, Magnaflow 4x14 bullet-style muffler, 3" mandrel tailpipe
Hybrid lift, 31" Firestone Destinations

I dyno'd at a different facility in the fall, to the tune of 180/243. The intake, manifold, adapters are the only changes. the tune has also been modified to reflect the new mods.

My best pull was 196whp/255wtq. I am unsure of the validity of these numbers, as my pull took a LONG time to do (30 seconds? WTF). My vehicle was not listed in their load factor database :lol::lol::lol::lol:

I suspect they may be slightly underrated. I have calculated my parasitic loss to be approx 32%.

There is more in it, as around 5300 on black puffs of smoke came out of the tailpipe, indicating a very rich mixture (12:1 and falling) . It is currently being re-tweaked and corrected. 5000 rpms is where I made peak HP and also where AFR took a nosedive, so with the new tweaks I am making I should be above the 200whp mark.

The Dyno operator was a real tard, I told him how to get a clean 3rd gear pull and he still screwed it up. Here's a video, NSFW due to some language.

http://www.youtube.com/watch?v=eam-z850oGo
 
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#3 ·
I have bolt ons with a upgraded intake manifold, with big heavy tires to throw around. So the numbers will never be quite right.

Rotational mass factors into the numbers, which is factored in the percentage of drivetrain loss. If my math is correct, my crank numbers should be around 290hp/375tq......Which sounds about right to me.

I know I'm making significantly more power than before....the manifold plus a tweaked tune was enough to take .3 off my 1/4 time in the back 1/8th of the track alone. I go by track times and not dynos, so I'm not feeling any opinion in particular in regards to my numbers.
 
#4 ·
mmmmm...290/375???? I dont know bro...maybe if you were cammed. The guy was a peckerhead huh? The number seem real good to me....congrats!
 
#6 · (Edited)
Well....I've got a backed up 3 tenth improvement on my old setup versus new. It was all in the back 1/8th of the track...and the DA correction is negligible. I say this because the DA was near 0 on both runs.

Let's assume the dyno numbers were spot on. Being a new dyno, and being a mustang dyno at that, I'd be inclined to think that if anything the numbers are slightly lower than what they could/should be.

25% losses (this is a % usually seen by Hemi Rams with no t-case and the same transmission) would equate to approx 265/ 340.

30 pct losses (which is reasonable when you add a t-case into the mix) would equate to 280/365.

Because I have larger tires than stock (and heavier), I factored in an extra 2%.

I am not running cams but I do not tell all of my mods....Cams help, but power can be made without them.
 
#7 ·
My best 1/4 time to date is a 15.58 @ 88.

My best 1/8 mile time is a 9.982 @ 71.

Those were 2 separate runs (using the multiplier from the 1/8 time to the 1/4 time from the 15.58 run and factoring it into the PB 1/8 time, I got a 15.47)

Neither one of those times is with my current setup. I'm going to the 1/8th mile Thurs, we will see what happens.
 
#10 ·
If I ever do stuff cams in it, they'll be HOs. the 206 grind has too much exhaust duration for my liking. The "fixed" form of that grind, the 212/212, hasn't performed that well either, in a 4000+ lb truck anyhow. I had a set, sold them.

The HOs will be sneakier, easier to 0 out the fuel adaptives, and keep the power curve low, where I need help.
 
#17 ·
Yeah yeah yeah.....Thankfully I got other mods I can still do before I need to worry about cams.

I loved the HO 206 in my gen 1 4.7...made a huge difference in my opinion and through some superchips times I recorded
the 206/218 grind works, and I'd see a gain from it but this 08 manifold really changes everything. If I was still running a Gen 1 manifold or had a converter, I'd be more inclined to run a hotter profile. Not to mention I'd rather have something easier to tune.

I got some stuff in the works this summer....I need to determine what route I'm gonna go.
 
#16 ·
I loved the HO 206 in my gen 1 4.7...made a huge difference in my opinion and through some superchips times I recorded
 
#21 ·
I'm not the one who dropped nearly a G on a converter there, Spanglish.

Vehicle
Weight1/4 Mile
Trap MPHYour Estimated
Net Horse Power

This is from a horsepower calculator from Great Lakes Dragaway. I estimated your weight. Not sure how accurate.

Horsepower Results - 1/4 Mile MethodYour Jeep weighs about 5000 pounds and can complete a 1/4 mile in about 15.58 seconds. That means that you've got about 261.31 HP at the wheels, and about 339.70 HP at the flywheel.
Vehicle
Weight1/4 Mile
Trap MPHYour Estimated
Net Horse Power
My weight is probably closer to 4600 lbs.

So Gen 2 4.7L intake is better on GEN 1 4.7L... this just a drop in? (minus an adapter for throttle body)
It wasn't on my WJ (I did not know this until I was into the install) and it won't be on your WK.

I had to cut the firewall to get it to fit. On yours, you may need to cut the firewall as well as get a 08 EGR system.

Additionally, you will need a custom tune. It will run on a stock PCM cal, but WOT AFRs will be extremely lean. Superchips is not enough.
 
#20 ·
So Gen 2 4.7L intake is better on GEN 1 4.7L... this just a drop in? (minus an adapter for throttle body)
 
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