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- #41
Fixed my rear end finally!!
Build Absalom's HDJ81 Build Thread - Restomod
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- #42
Got a dyno test today for fun/emissions after moving to Colorado. She passed with flying colors ... 8% max opacity out of an allowable 35% and 163 hp at the wheels! Not bad for the old girl.
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- #43
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Did you get a torque figure, and graph? 163hp at the wheels means you're making enough extra power to overcome the driveline losses.
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- #45
I didn't
The dyno is purely for emissions, and the HP figure was provided as a courtesy of the emissions tester. I know there's a particular brand of dynos that tend to inflate horsepower figures, does anyone know if Mustang dynos tend to run high?
Mustangs are the most configurable and tend to either run high or low depending on how the operator has it setup. I know a mustang dyno that is a heart breaker and reads about 10-13% low but I know another that reads 20% high. That's why most often you will hear people say you need to compare your before and afters on the same dyno for it to be meaningful.
dynojets will almost always have the highest numbers. There is also a lot of fudge factor in the calibrations and "correction factors" used by the operator. But your mustang dyno numbers are probably not bogus. FWIW, my stock LX put out 120hp on a superflow dyno in the Denver metro. :edit: Ryan beat me to it.
Makes me think the dyno operator has it set to calculate drivetrain loss, or that truck has been turned up a little. If the OP has a friend in the area with a 1FZ cruiser it would be cool to see if it shows 212hp or 140ish
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- #50
That's a great thought and was my initial guess. However, the operator was very clear that the posted number is at the wheels, and he even went on to estimate power at the crank, taking into account slushbox, transfer case, etc. I suspect 3" exhaust, 14 psi, and minor (emphasis on minor) pump mods are enough to compensate for drivetrain loss.
I'm more shocked that after 25 years she's making the EXACT amount of power that she left the factory with, something no gasoline powered automobile will ever be able to say without an extensive overhaul.
Not running an intercooler with the 14psi? EGT gauge? I'm curious since my HDJ81 should be here in a few days and 3" exhaust and 14psi are my initial plans.
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- #52
Not yet. 14 psi is considered the efficiency threshold for the stock turbo, and a lot of folks say IC isn't required at this stage. The fueling is what really ratchets up the EGT's. Don't get me wrong, I'm drooling over 81 IC kits on Alibaba, and G-turbos on an almost daily basis! I'm stoked for you to get yours. Be sure to post up your progress and impressions.
You and me both. Good to know that an intercooler is not totally necessary for 14psi. I'm thinking I may just fab up a front mount at some point. There is a chance she will be delivered tomorrow so I'm excited. She is super clean but now, like you, I dont want to mess her up. It should be a huge upgrade over my 2h but at least I could throw lumber in the back of my 62 and not care.
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- #55
Finally got her badges back on following the paint job. Very happy with how they turned out, hard to believe they aren't from Toyota!
The interior looks amazing!! I just picked up a 1991 from LCD and they mentioned the Japanese love to smoke in their cars; gratefully the one I chose seemed to be one of the rare non-smoker owners and the interior is in stellar condition, except for the center console where the cooler/ice maker is. Ill check out the paints! Enjoying your posts, so far!
Adding boost alone won't be likely to increase power much, if at all (depending on the current tune)
Power is a result of fuel burnt. Want more power, burn more fuel. Adding boost lets you burn more fuel, which in turn helps make more boost, so on, and so on. The two are linked.
Increasing boost without fuel adjustment will likely give you cooler EGTs (good for engine longevity).
A big increase in boost may not actually be achievable without adding fuel, boost is also a byproduct of burning more fuel.
Trying to increase power without touching the fuel pump is kind of nonsensical.
Adjusting the fuel pump is essentially the same idea as adjusting mixture screws on a carby, or reprogramming the fuel map for an efi system
There's a few pitfalls to tuning a diesel, the engine and fuel characteristics are different to a gas engine.
There's loads of info on tuning these engines in the diesel tech section
While I completely agree that if you're tuning for power you'll need to add fuel, increasing boost has the effect of extending the powerband before things level off in my experience. You don't gain much in the way of peak numbers, but rather add useable rev range before more revs just equal more noise if that makes sense. Adding 500rpm to your powerband is a big deal on a low revving diesel, I found the truck much nicer to drive on the highway with boost increased to 15psi and no fueling changes, and ran much cooler to boot.
Would you mind sharing the SEM PNs for your center console restoration?