Max boost on 1hd-ft

[adrian00]

what do you think the max safe boost is for a 1hd-ft with a safari intercooler ???

[Behemoth60]

I know that anything over about 1000psi can be pretty dangerous in the event of containment failure. But even a large volume of air at just 4PSI can kill you under the right circumstances (like trying to seat the bead on a tractor tire and the tire blows out), but those circumstances are unlikely in a turbo system. I would say that as long as the hood is down and you're behind the firewall, if there was a catastophic failure of the intake manifold, it's unlikely that any of the shrapnel could penetrate the sheet metal and harm your or family in the vehicle. If you were really concerned, you could probably wrap your intake in some sort of balistic blanket like racers do for their clutch plates. Then you can safely run somewhere into the low thousands of psi. Probably no more than about 3,500psi though.

While the boost would be safe, the power you could make with 3,500lbs of boost would be 'killer'. Some of the drag trucks are making 1100hp and 2,500 ft-lbs with just 50psi. The most I've ever heard of is about 160 psi boost in a detroit diesel drag truck. I doubt you can make anything even close to that much boost, so I would say your safety is unaffected by even the most boost you can practically feed into a 1HD-FT.

Peter Straub

[Towpack]

If the engine is mechanically sound the limiting factor will be exhaust temperature.Too much boost and something will probably seize or melt long before anything broke mechanically.Many engines with big boost/power run water injection systems.If you want to experiment fit a pyro gauge.

[SamB]

Originally Posted by Towpack

If you want to experiment fit a pyro gauge.

What would be the max temp to run before the turbo??

[Technikev]

Originally Posted by Behemoth60

I know that anything over about 1000psi can be pretty dangerous in the event of containment failure. But even a large volume of air at just 4PSI can kill you under the right circumstances (like trying to seat the bead on a tractor tire and the tire blows out), but those circumstances are unlikely in a turbo system. I would say that as long as the hood is down and you're behind the firewall, if there was a catastophic failure of the intake manifold, it's unlikely that any of the shrapnel could penetrate the sheet metal and harm your or family in the vehicle. If you were really concerned, you could probably wrap your intake in some sort of balistic blanket like racers do for their clutch plates. Then you can safely run somewhere into the low thousands of psi. Probably no more than about 3,500psi though.

Umm... what?

IMHO it is unlikely that you will blow up your intake. If too much boost, probably just blow off an intercooler piping flex boot or a gasket. Personally I would limit boost to around 20 PSI, but I would increase it incrementally. I believe you would be absolutely safe at 15 PSI. Excessive pressure will probably lead to some unreliability. I think Crushers was running about 14-15 PSI in his turbo'd 75 with a 1HZ. And he had propane to boot.

Remember that its not just boost that gets you power, but fuel also. The higher boost just gets more air in to burn the extra fuel. Get a pyro. 1100 - 1250 PSI max. Have fun.

-kevin

[crushers]

yep 15 lbs max with PI and didn't have a concern either with the engine of the EGTs and that bugger is way overfueled...
too much boost and the heat from compression kills the advantage of the boosting due to expansion of gasses...
or so i have been informed...

[Tapage]

Originally Posted by Technikev

Umm... what?

IMHO it is unlikely that you will blow up your intake. If too much boost, probably just blow off an intercooler piping flex boot or a gasket. Personally I would limit boost to around 20 PSI, but I would increase it incrementally. I believe you would be absolutely safe at 15 PSI. Excessive pressure will probably lead to some unreliability. I think Crushers was running about 14-15 PSI in his turbo'd 75 with a 1HZ. And he had propane to boot.

Remember that its not just boost that gets you power, but fuel also. The higher boost just gets more air in to burn the extra fuel. Get a pyro. 1100 - 1250 PSI max. Have fun.

-kevin

1100 - 1250 ºF I mean ..

[Technikev]

Geez, nice catch. A bit of a brain fart with all this talk of PSI and exhaust temps.

Yeah, max EGT is 1100-1200 DEGREES. LOL

-Kevin

[freebornred]

W T F !

Originally Posted by Behemoth60

I know that anything over about 1000psi can be pretty dangerous in the event of containment failure. But even a large volume of air at just 4PSI can kill you under the right circumstances (like trying to seat the bead on a tractor tire and the tire blows out), but those circumstances are unlikely in a turbo system. I would say that as long as the hood is down and you're behind the firewall, if there was a catastophic failure of the intake manifold, it's unlikely that any of the shrapnel could penetrate the sheet metal and harm your or family in the vehicle. If you were really concerned, you could probably wrap your intake in some sort of balistic blanket like racers do for their clutch plates. Then you can safely run somewhere into the low thousands of psi. Probably no more than about 3,500psi though.

While the boost would be safe, the power you could make with 3,500lbs of boost would be 'killer'. Some of the drag trucks are making 1100hp and 2,500 ft-lbs with just 50psi. The most I've ever heard of is about 160 psi boost in a detroit diesel drag truck. I doubt you can make anything even close to that much boost, so I would say your safety is unaffected by even the most boost you can practically feed into a 1HD-FT.

Peter Straub

[Dave]

Originally Posted by adrian00

what do you think the max safe boost is for a 1hd-ft with a safari intercooler ???

Have you ever had the head off a 1HD-FT? The valves are very close together. There is almost no metal between them. Running higher bosts can lead to head cracks on these engines. Want to see some photos of what they look like? It costs a lot to buy a new head.

[tlcruiserman]

Originally Posted by adrian00

what do you think the max safe boost is for a 1hd-ft with a safari intercooler ???

I am running a max of 14lbs of boost on my HJD80L with 1HD-FT I have an aftermarket intercooler. recently I turned up my fuel because I was rarely hitting 800F on my egt's now that fuel it turned up (huge difference in power) I am around 800f on flat road under load and on hills with trailer in tow (6000lbs towing) maybe I hit between 1000 - 1100F at the most. Truck is dialed in works great

Cheers,

Michael

[Behemoth60]

Originally Posted by Technikev

Umm... what?

IMHO it is unlikely that you will blow up your intake. If too much boost, probably just blow off an intercooler piping flex boot or a gasket. Personally I would limit boost to around 20 PSI, but I would increase it incrementally.

Adrian00 was asking how much boost is safe. 20psi is a no-brainer. A leaf blower can make 20psi. There's nothing dangerous about that.

The discussion about how much boost you *should* run for engine longevity, power, etc. has been discussed to death, but how much boost could *cause* your death or other bodily harm is an interesting new topic that adrian00 has tabled in his inquiry about safety.

I'm not sure why you guys are yammering on about 15-20 lbs of boost and won't contribute an on-topic post to this guys query.

Peter Straub

[tlcruiserman]

Originally Posted by Behemoth60

Adrian00 was asking how much boost is safe. 20psi is a no-brainer. A leaf blower can make 20psi. There's nothing dangerous about that.

The discussion about how much boost you *should* run for engine longevity, power, etc. has been discussed to death, but how much boost could *cause* your death or other bodily harm is an interesting new topic that adrian00 has tabled in his inquiry about safety.

I'm not sure why you guys are yammering on about 15-20 lbs of boost and won't contribute an on-topic post to this guys query.

Peter Straub

Your right Peter, I was just Yammering on what I run on mine, I did not even think of running up until a blow a perfectly good 1HD-FT what was I thinking For what its worth Adrian00, I think you should run it as high as it will go until you blow it into pieces and then let us know so I don't run it that high, mybe a long term report so if goes in a month we can still get the data

Michael

[crushers]

max SAFE boost was his question...

for Peter, who rebuilds his engines every time he changes his oil, max boost is what ever the turbo will produce.
for the rest of us max is about 15psi...
cheers

[Behemoth60]

Originally Posted by crushers

max SAFE boost was his question...

Great point, Wayne. It seems we all mis-interpreted Adreian00's question. Clearly, he's a jewel thief and using his engine to compress the air inside a safe to crack it open. In that case, maximum safe boost would be dictated by the thickness of the walls of the safe, the grade and treatment of the steel, the mechanics of the construction, the seals used to contain the air inside, etc. A much more interesting question when you think of it that way.

Peter Straub

[crushers]

this is true, max safe pressure for a steel object is much higher than say an air line to your skin...

[tlcruiserman]

and here I thought we were talking about diesel engines to power your auto down the road

[blownbj]

you Guys are always carrying on about how much boost is safe and what air pressure can do but which one of you has ever popped your cylinder head and could contribute it to overboosting. I don't think there's one!! It sounds like alot of urban folklore I knew a guy who knew a guy who... I would for once like to here a testamonial of someone with a blown 3B that could contribute it to giving it too much fresh air and not overfueling or overrevving.

[crushers]

feel free to acomplish your own task and let us all know the results of your test...

[Behemoth60]

Originally Posted by blownbj

you Guys are always carrying on about how much boost is safe and what air pressure can do but which one of you has ever popped your cylinder head and could contribute it to overboosting. I don't think there's one!! It sounds like alot of urban folklore I knew a guy who knew a guy who... I would for once like to here a testamonial of someone with a blown 3B that could contribute it to giving it too much fresh air and not overfueling or overrevving.

Finally, someone else out there is starting to see things my way. Indeed, I've said it before, I don't think the max safe boost for a 3B/13B-T has been established yet. When a repeatable failure happens to a decent sampling of engines which were using a set amount of boost, we can start to draw some conlcusions. But no one, EVER, that I know of, has wrecked ANY part of their Toyota engine due to boost alone.

Everyone, please go turn up your boost TODAY! We need to start collecting some data.

Peter Straub

[blownbj]

Hey peter what kind of setup do you run and how much boost are you pushing? What kind of EGT's are you running @ and how many ponys are you generating?

[Tapage]

Originally Posted by Behemoth60

Everyone, please go turn up your boost TODAY! We need to start collecting some data.

Peter Straub

I thought if gona pay for all break engines .. all can do that .. ! ( joke )

[Behemoth60]

Originally Posted by blownbj

Hey peter what kind of setup do you run and how much boost are you pushing? What kind of EGT's are you running @ and how many ponys are you generating?

AXT turbo kit on a 3B with the high-nickel aftermarket head. Wastegate signal line is tied off so the wastegate doesn't open. Actual boost is unknown as it pins the 0-15 PSI gauge. Max EGT I've seen since I've turned it up has been 400C. Keep in mind, this is strictly an off-road wheeling rig. That 400C EGT was when I was bombing down the road for 1/2km to fling the mud out of the tires.

Peter Straub

[silvercrusher]

Since you have the wastgate "pinched off" I am assuming you were going for low to midrange horsepower for wheeling. Just curios but when approx. do you think the turbo is hitting max boost (at what rpm). I have always wondered what would happen if i did not allow a turbo to have the ability to bleed pressure.

On deceleration what has been your experience?

Cheers
Challis

[silvercrusher]

Sorry one more question.
Have you had any indication of the turbine surging or pulsing at idle with the gate pinched ?

Very interesting topic thanks for your experiment.

Challis

[Behemoth60]

Originally Posted by silvercrusher

I am assuming you were going for low to midrange horsepower for wheeling.

No. Blowers are for low/mid range power. Turbo's make best top end power. That's what I need for for mud and hill climbs. the 3B makes enough low and mid range power.

Originally Posted by silvercrusher

Just curios but when approx. do you think the turbo is hitting max boost (at what rpm).

4000 RPM. With the waste gate closed, more RPM = More boost.


I have always wondered what would happen if i did not allow a turbo to have the ability to bleed pressure.

Originally Posted by silvercrusher

On deceleration what has been your experience?

Quite often, it's sadness at having to slow down. Other times, it's delight and relief, such as when slowing down at the edge of a road-runnerian cliff.

Originally Posted by silvercrusher

Have you had any indication of the turbine surging or pulsing at idle with the gate pinched ?

Surging and pulsing are two different things. Surginging is when the compressor is turning too fast for the air it is pushing. This is caused by a mis-matched compressor, and I've heard can cause catastrophic failures.

Pulsing is a feedback loop from the wastegate. Pressure builds up, the wastegate opens and slows the compressor. The pressure drops and the waste gate closes. Pressure builds up, the wastegate opens... Repeat every 1/2 seconds or so. This can solved by putting a very small, like itty bitty, I mean, line between the pressure sender and the wastegate actuator so the pressure changes slowly in the wastegate actuator. Or, pinch off the wastegate entirely.

I've never had surging, but did have pulsing before I closed off the wastegate. Neither should ever happen at idle.

Peter Straub