then 19psi was best for 1HD-T, as i got a mechanic, he adjust mostly to 19psi 20psi the car is very powerful, if in series 80, got one of his customer, for a short period and distance, modify turbo , intercooler, fuel pump, such, run 180kmh in a while
1HDT w. 3" exhaust - incredible results
- Thread starter Martin White
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then 19psi was best for 1HD-T, as i got a mechanic, he adjust mostly to 19psi 20psi the car is very powerful, if in series 80, got one of his customer, for a short period and distance, modify turbo , intercooler, fuel pump, such, run 180kmh in a while
- Thread starter
- #62
Interestingly, many told me there would be no power difference going to a 3" system. I just found out from John at Ateb that he never touched the fuel screw. This is amazing to me. All I can say is that those who said there'd be no power difference were just flat out wrong. Not only is there an increase in power but it is very significant. HP calculators based on timed runs indicate approximately 13-14% more power, and WAY more down low in the RPM range.
I don't know what % of this may be due just to the exhaust or if any of it is due to the aeroturbine. I was very skeptical about their adverts. But I can not argue with the results. Anyone who has read my posts over the last year knows I am not overly prone to make unsubstantiated claims. If I had cheap access to a dyno it would be very interesting but to get meaningful data would cost more than I want to spend.
I don't know what % of this may be due just to the exhaust or if any of it is due to the aeroturbine. I was very skeptical about their adverts. But I can not argue with the results. Anyone who has read my posts over the last year knows I am not overly prone to make unsubstantiated claims. If I had cheap access to a dyno it would be very interesting but to get meaningful data would cost more than I want to spend.
Tapage
Club 4X4 Panamá
2H it's a IDI and the 12H-T it's a DI engine .. huge diference .. Anycase I was so scary to put 27 psi in any toyota engine with stock internals ..
To get that big an increase, there must have been something badly wrong with your old exhaust.
Aeroturbines don't work, it's not that.
Do you run a boost gauge? If so has there been an increase with the bigger pipe?
You're only going to get an improvement if your current system is really restrictive.
Measure the backpressure after the turbo and see what it is.
Anything less is guesswork.
- Thread starter
- #67
Yes, I've been running an ISS Pro boost guage for some time. The boost is exactly the same as it was before the exhaust work, factory stock at about 11.5 PSI. It now boosts MUCH faster than before. Other than the exhaust no other changes were made to pump timing, fuel load or anything else. The only thing that changed is the exhaust. A friend of mine drove it and he also noticed the difference right away.
I should add that I had turned the fuel down so far that I was thinking about bumping it up a touch again, as the truck was very sluggish. So given that the fuel screw was not turned up, I am even more amazed.
The old exhaust has been autopsied now and there is no evidence there was anything badly wrong with it, other than that crimp they put in it when it goes over the frame rail on the stock system, and generally it was getting very tired. I was told the crimp was there because Toyota was restricted at the time in Japan to engines that put out less than 300 ft lbs or torque and that the crimp restricted the engine to a figure less than that. I can't verify that story but I CAN verify my truck is putting out massively more power now than before.
I know what you are saying about the aeroturbine. I was very skeptical because I could not find any data I could believe that would support the figures they have claimed. But based on my results I'd have to say that something is going on here. I don't see any change in fuel consumption (yet, too soon to say) but the power figures speak for themselves.
Perhaps there was a hidden restriction in a pipe somewhere that was not found. That is certainly possible.
I should add that I had turned the fuel down so far that I was thinking about bumping it up a touch again, as the truck was very sluggish. So given that the fuel screw was not turned up, I am even more amazed.
The old exhaust has been autopsied now and there is no evidence there was anything badly wrong with it, other than that crimp they put in it when it goes over the frame rail on the stock system, and generally it was getting very tired. I was told the crimp was there because Toyota was restricted at the time in Japan to engines that put out less than 300 ft lbs or torque and that the crimp restricted the engine to a figure less than that. I can't verify that story but I CAN verify my truck is putting out massively more power now than before.
I know what you are saying about the aeroturbine. I was very skeptical because I could not find any data I could believe that would support the figures they have claimed. But based on my results I'd have to say that something is going on here. I don't see any change in fuel consumption (yet, too soon to say) but the power figures speak for themselves.
Perhaps there was a hidden restriction in a pipe somewhere that was not found. That is certainly possible.
How about mufflers?
They make a much bigger difference to restriction than pipe size does.
Your performance gain is likely not the result of the muffler. But, getting rid of any piping crimp that restricts flow probably did. I don't know what was on there before, but if it was less than 2.5 inches it was likely too small.
As an example compared to, say a cummins diesel, which may have a factory exhaust of 3.5 inches (I don't know and am just making an educated guess), based on displacement alone, you should have an exhaust of 2.5 inches. With the old exhaust, you had the factory crimp restricting flow and the fact that the 1HDT likes to rev higher so would tend to produce more exhaust gasses than an engine revving no higher than 2 grand (Cummins), this would make sense. From a numbers perspective in my twisted world, that is...
As for mileage, you will undoubtedly find that until the excitement of newfound power and silly grin wear off your face, you will get WORSE mileage. Funny how more power suddenly makes your right foot heavier...
Have fun.
-kevin
Martin, some light reading for you: https://forum.ih8mud.com/showthread.php?p=1419158
The design of the Aeroturbine muffler is basically to chop the sound with as little back pressure as possible. It does this in my experience.
gb
Rust Blues
When I did my first body job many years ago I found out the hard way that bare steel rusts in TWENTY MINUTES in the ambiant air. It was clearly and visibly changing color after just a short lunch break. And that was in summer! Granted, we tend to have humid summers here...
My old BJ60 has had a rear wheel well treatment that has held superbly well after many years because it was zinc primed less than 5 minutes after it was sandblasted, and then completely covered in rubberized caulk when I came home from the sandblaster's in the couple of hours. Not an iota of rust has reappeared where the treatment was done.
Heck, even my 316 grade SS licence plate holder on that thing rusted within the next day after installation!!! But it was most probably due to fine steel particles sticking to the SS... Buffing lightly with SS polish took care of it.
When I did my first body job many years ago I found out the hard way that bare steel rusts in TWENTY MINUTES in the ambiant air. It was clearly and visibly changing color after just a short lunch break. And that was in summer! Granted, we tend to have humid summers here...
My old BJ60 has had a rear wheel well treatment that has held superbly well after many years because it was zinc primed less than 5 minutes after it was sandblasted, and then completely covered in rubberized caulk when I came home from the sandblaster's in the couple of hours. Not an iota of rust has reappeared where the treatment was done.
Heck, even my 316 grade SS licence plate holder on that thing rusted within the next day after installation!!! But it was most probably due to fine steel particles sticking to the SS... Buffing lightly with SS polish took care of it.
What a Revelation!!!
And I thought it was a defect on mine!!! Gaw! Now that you mention it, I did notice yesterday looking at old HDJ81 pictures from auctions and sites last year, that there is indeed a crimp (as if the pipe had been pinched by accident) right above the rear shock absorber mount tube!!!
As a matter of fact, until I noticed after winter that the pipe had some leaks, I was going to correct to replace that section...
Hail to the chief! Thanks, Martin, for revealing it to us!!!
And I thought it was a defect on mine!!! Gaw! Now that you mention it, I did notice yesterday looking at old HDJ81 pictures from auctions and sites last year, that there is indeed a crimp (as if the pipe had been pinched by accident) right above the rear shock absorber mount tube!!!
As a matter of fact, until I noticed after winter that the pipe had some leaks, I was going to correct to replace that section...
Hail to the chief! Thanks, Martin, for revealing it to us!!!
What about the turbo seal? I thought that exceeding 13 PSI would blow the seal (causing oil to be pumped into the intake manifold)
You've never been to the northeast of the North American continent, it shows!!!
I live in the area on the map bewteen the 4.3 and 4.0 acid rain zone, where it's bluest (more than 4 tonnes of salt used for roads per mile)
Actually in winter, the cars get so covered with salt the color is hardly visible, if you don't wash them twice a week.
We have a SERIOUS issue with rust here!
Three or four months ago, during the last cold spell!!!
I'd move!
Seriously what a crappy place to live....... I love the fresh air and clean rain I get just 350 kms in from the ocean. It makes me wonder why people put up with living in Smog ridden acid rain places.
Aluminized pipes can last for a long time. If you don't have the cash to pony up for SS, you can paint your exhaust with high heat paint each year. It will slow down the rust. Also living in salt belt you should be having your truck oiled each year. Otherwise it will not last.
Go to alberta and BC and vehicles last a really long time. Very little salt used and clean rain.
thats cool that your 81 has responded well to an exhaust upgrade. I thought i would mention about my success with intercooling- had an 87 jetta TD (i know its not quite a direct comparison) had 410,000 original kms when i intercooled) it boosted my milage from 850 kms/55 liters of fuel to over 1000 in comparable driving and as high as 1110 kms. Also i went from about 90 km/h over the coquihalla ( i think you are from the lower mainland? ) to 125 in 5th gear. I did not tweak the pump or do anything else. Turbo boost was 9.5 lbs in both situations. Just my opinion that intercoolers are essential. I have a BJ60 that is going to get a turbo, intercooler, and exhaust all at once pretty soon.
Sssshhhhh!! Don't tell them or they'll all come out here and pretty soon we will all have the smog and acid rain, too.
Note to anyone not from the west: Its really crappy here. So much smog that I can barely breath on the way to work in the morning. And all the other nasty stuff, too. Ummm, yeah...
-kevin
Another note, brownbear: There's probbly more Newfie's in Fort MacMurray than in Newfoundland.
-kevin
-kevin
I believe this is a standard crimp, in even the FZJ80's. I've not looked under a Lexus 450, but I bet it's there too! Best thing you can do is remove it...
Fine:
EDIT = Best thing you can do in a diesel application is remove it and go larger unrestricted exhaust...END EDITgb
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Moral is...make a clean path to let the air in, and also to let the air out, and then make it dense. Hmmm, sounds like Banks Tech talk! http://bankspower.com/tech.cfm
gb
Has anyone got a picture of this crimp?
I don't believe the story about the 300 ft/lb of torque. Manufactureres measure engine power and torque without the vehicle and associated parts. Toyota's first passenger vehicle engine to put out anywhere near that was the intercooled 1HD-FTE which appeared in 99 inside the 100 series cruiser. 430Nm.
I really hate quoting wikipedia, but this one seems accurate.
http://en.wikipedia.org/wiki/Toyota_HD_engine
