300+ hp to the wheels from a 1hd-t?

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p0opstlnksal0t

p0opstlnksal0t

10 Year
Joined
Sep 6, 2014
Threads
11
Messages
157
Location
Houston, Tx
Does anyone make aftermarket injectors or pump upgrades for these motors? Im looking at a nice rhd hdj81 with the 1hd-t and iI'mtrying to weigh the options vs a mechanical 4bt cummins swap. I would prefer the route of the oem toyota 1hd-t motor. How hard is it to see 300+hp at the wheels? Would a built (valve body, tq converter, possibly upgraded clutches if i can find them) a442f stand up to the power/tq or would a 5 spd manual with an upgrades clutch be a better option? I've seen guys in Aus. Running 14mm IP's, does anyone in the states build aftermarket ip's for these trucks? Turbo.and.intercooler would be the easy part. I'm guessing 30-35 psi should be ok on the stock head. It'seasy enough to retorque head studs. Would arp studs even be necessary at this level? Sorry for all the new questions
 
You should be able to get 300 rwhp without too much trouble, you'll need a fuel pump and injectors designed to move enough fuel to do that. I've been happy with the gear I got from XXiindustries, some others haven't been. Most performance upgrades here use a 12mm pump as apparently a 14mm is to difficult to make drivable, and a 12mm can provide enough fuel. GTurbo can supply a turbo to make the boost you'll need, I would think about 35-36 psi. You'll need a high-flow airbox, I recommend Moonlight fabrication in Perth for this. I can't comment on the auto transmission but I know my XXi Clutch holds the power fine.

@Rob1983 might be able to comment further
 
Should add, you'll also need a good intercooler and most likely, intake manifold modifications
 
IanB said:
There's probably 20-30 1HD-T's in the US at this point in time, you'll be shopping abroad for aftermarket parts for this engine.

Correct.
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ya that makes sense, i guess ill just have to add a good 30% to the costs in order to get the parts shipped here hahaha

so the stock pumps on these rigs are capable of 300 whp, what mods are people doing to these pumps to get the fuel needed? Ive seen quite a bit of info in regards to reprofiling the metering rod, what other mods are needed to these pumps to get the pumps capable of supplying so much fuel?
 
Most importantly you need to match the fuel flow of the pump to the boost of the turbo. Look up the threads by Graeme here, he explains it pretty well. So you will need a matched pump, intercooler, turbo and exhaust to get max power with minimal heat and appropriate AFR.

300hp is pushing it though, IMO. No matter how well your system is built, there will be a trade off between power and longevity.
 
p0opstlnksal0t said:
ya that makes sense, i guess ill just have to add a good 30% to the costs in order to get the parts shipped here hahaha
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Don't forget about importation tariffs and other such BS. I got a call from a collections agency yesterday for a $36 FedEx bill I didn't even know about! The order was $435 with $53 in shipping (all small lightweight items), then this unknown cost.

And hopefully the language on the customs forms doesn't imply items related to safety, like seat belts, because it will spend a bunch of time on their shelf before being released to you.
 
Jan-78FJ40 said:
300hp is pushing it though, IMO. No matter how well your system is built, there will be a trade off between power and longevity.
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this it's for sure important .. if you are planning on full boost driving floored all the way .. if you know how to take care of your engine .. I would not be too concern, knowing for sure that this is not an tow engine like the cumins are ..

you might wanna check here for tranny upgrades ..

Wholesale Automatic Transmissions

mentioned turbo ..

GTurbo™ - Engineered Diesel Performance
 
I've got a 1HDT running 38psi at 18:1 afr, currently with a gturbo. It made 250rwhp on 35's with the previous turbo, a garrett GTX3071R, on 35psi at 21:1, so a fair bit less fuel. Am using the same pump, but I've tickled it up a bit since the initial tune ;) Haven't had a chance to get it back on the rollers since the turbo swap, but due to the increased fuel and boost as well as quicker turbo response I'm hoping for a nice increase in ponies. It's a hi flow 12mm pump, 14mm is overkill and a dog to drive on the road, this pump isn't even maxed yet, need to run 45+psi to safely max the fuel on it. Also running w2a intercooler, upgraded intake path (airbox, snorkel etc) and 4" dump pipe. Stock internals
 
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Rob1983 said:
I've got a 1HDT running 38psi at 18:1 afr, currently with a gturbo. It made 250rwhp on 35's with the previous turbo, a garrett GTX3071R, on 35psi at 21:1, so a fair bit less fuel. Am using the same pump, but I've tickled it up a bit since the initial tune ;) Haven't had a chance to get it back on the rollers since the turbo swap, but due to the increased fuel and most as well as quicker turbo response I'm hoping for a nice increase in ponies. It's a hi flow 12mm pump, 14mm is overkill and a dog to drive on the road, this pump isn't even maxed yet, need to run 45+psi to safely max the fuel on it. Also running w2a intercooler, upgraded intake path (airbox, snorkel etc) and 4" dump pipe. Stock internals
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Has anyone approaching these power levels gone for a custom cam grind? Seems to me the stock head/valves/camshaft would be a big limitation to getting all that air into the cylinders. I imagine it would free up a lot of power? I suppose going to the 24V 1HDFT(E) head (engine) would do the same to improve flow?
 
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GTSSportCoupe said:
Has anyone approaching these power levels gone for a custom cam grind? Seems to me the stock head/valves/camshaft would be a big limitation to getting all that air into the cylinders. I imagine it would free up a lot of power? I suppose going to the 24V 1HDFT(E) head would do the same to improve flow?
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As far as I know, the HDFT head will not bolt to the 1HDT block.
 
Jan-78FJ40 said:
As far as I know, the HDFT head will not bolt to the 1HDT block.
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Sorry, I meant going to the entire engine, not just the head. I just meant to focus on the head as one of the main differences between the two in terms of power potential.
 
mudgudgeon said:
Also search this section for all "the official 1hd-t. . . . ." threads.
If you have a few rainy days to kill, there's loads of good info and interesting discussion here.
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They are all listed in FAQ! No need to search! :beer:
 
The FT head will bolt up, but you need to change the ip, lines, timing setup etc. Fair bit of work and probably work out cheaper to buy one lol
 
But, yes, the restriction is in the head's flow capacity
 
Although from what I can determine, a 1HD-T with a properly modified intake manifold should flow better than a stock 1HD-FT which can't have the manifold modified due to the injector lines over the top
 
From previous comments by Grahame (gturbo), there is little benefit from the 4 valve hd-ft head until high in the RPM range.
So probably not really worth the effort, and the premium price for 1hd-ft stuff.

Custom intake manifold and some mild porting and port matching of head and manifolds is where I'd be looking. Porting can be done at relatively low cost with potential for improved flow.

Custom cam grind could be interesting. I think maybe gerg?? had a custom grind done for a 3b?? with little gain.
 
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