1HD-T Intake Manifold Modifications

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i do not know johns turbo numbers , and no i am not running an aussie turbo. this one is designed and built in vancouver. the point i am trying to see is the fact that ,my power is not from my custom turbo,but from fuel pump tweeking and improved air flow via an intake manifold mod. bottom line is i am trying to keep my truck pretty much in the class of backyard builds ,where an average guy after a proffesional pump tweek tune can build and maintain on a dime budget , locally.

Can't say I really agree with this. All your doing with the pump is correcting fuel to your turbo's needs (which a stock pump does easily). Its your turbo that dictates when boost kicks in and holds that boost too (keeping it inside its efficiency range). Most companies/people tune them for correct afr's under load. It's still an art to tune them preboost/on boost. And that's what gives you great drivability. This is why Graeme's turbo's are so great. They are matched to that engine. The intake manifold mod is dependant on boost level, VE/cfm etc. I would still do it to a stock engine. But the size would change.
 
im suprised other parts of the world are not trying to import atebs fuel mods, like were trying to get what we do not have here ,but to date the extreme v/b is still the over seas slow boat. for now. curious about the ve ,cfm numbers ? still stock ? you say you hate the front entry style intake . i thought it was best with the front mount cooler design (old supra junkyard find )being a shorter run and one less 90 *.you guys over there have a surplus of manifold designs to use at your disposal ? contacts please ,im sure they could sell a bunch ,i would have bought one intead of designing one, (oxygen tank ,from the srap yard) and yes i know its a gamble with the under 300 dollar turbo but if the numbers work the numbers work.
 
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Can't say I really agree with this. All your doing with the pump is correcting fuel to your turbo's needs (which a stock pump does easily). Its your turbo that dictates when boost kicks in and holds that boost too (keeping it inside its efficiency range). Most companies/people tune them for correct afr's under load. It's still an art to tune them preboost/on boost. And that's what gives you great drivability. This is why Graeme's turbo's are so great. They are matched to that engine. The intake manifold mod is dependant on boost level, VE/cfm etc. I would still do it to a stock engine. But the size would change.

I agree with that too. I would far rather have a better turbo and a stock fuel pump, than a stock turbo and a tweaked fuel pump.

Without the extra boost, it's just higher EGT and more smoke. The only way to make a significant gain on a diesel, is more and better boost.
 
graeme has a new turbo design to match the enlarged ported intake,interesting. tricky controlling surge ,with a tappered plenium. designing an intake is like designing a turbo. if that intake is 'proven', on ebay ,sounds pretty good ,you should buy it . i myself am pulling my custom turbo out (running 28 psi)and putting in a cheap chinese knock off (and hope i can boost it up enough to maintain my egts). my hp thinking is that atebs pump tune and fuel mods along with the tweeked manifold is all these trannies can handle extreme t/c ,v/b or not . oh i might add that atebs screaming prado that sailor is talking about is running the cheap chinese turbo too.

Why are you pulling out your custom turbo and installing a cheap chinese one? Is it failing or does it surge in the low rpm or when you wind out the fuel to save your transmission does it not have the low rpm boost response you require? Im playing around with my Bad By stage 2 spec at the moment - 20psi at 1600 no problem without having to dump smokey amounts of fuel in.

I dont have an issue with surge with my turbos. That is one of the key things - they flow high up top, they dont surge down low but develop high boost. I am building surge ported covers just to be sure - have supplied a couple already.

I also offer 5 comp wheels and 4 turbines to allow the optimum result depending on your goals and modifications. If you want to operate ~ 16psi and hold it flat from 1600rpm to the fuel cut and not have to wind fuel in too much dont in the low revs to make it boost, I have it - you want 20psi later on with more mods then no problem, it can do that. You want 30psi, you can have that too with different spec.
 
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im suprised other parts of the world are not trying to import atebs fuel mods QUOTE]

Honestly, theres nothing magical about the fuel mods. I supply atuning guide with all my turbos sold to the DIY community complete with detailed explanation of why you change what you change.

There is nothing, and I mean nothing, that anyone can do to these pumps (externally) that you cant do yourself for FREE with just a bit of time.

Power is NOT the issue with Turbos (power is easy) - its engine life and low rpm boost response with acceptable AFR's (EGT and smoke) thats the issue.

You can get 10psi on the stock 1HDT turbo at 1400rpm and a 3" exhaust if you wind fuel into it - plenty of smoke, but it does it. Drives a ton better however its not a sustainable condition.

That is the case on ALL upgrades I have seen for the CT26. Stick on a larger comp wheel, raise boost and dial in fuel and get power. When most people tune for power (wind up fuel) they dump heaps of fuel in at low manifold pressures (ie they dont tune properly and remove low boost fueling enough - its the hard part) and the turbo spools a ton better as a result. Then they say "look how great it spools". The reality is it spools slightly worse than stock but is aggressively tuned.

With my turbos, if you have tuned the pump (added fuel) in on the stock turbo, drive it around, then remove it and install mine, doing nothing else, you will IMMEDIATELY note a huge improvement in low rpm response - the auto owners will find the JDM 60km/h lockup in 4th AWESOME compared to a "pain". In this case, there are no tricks at all - simply swap and compare. Of course, this is more pronounced with the Grunter, however even the Bad Boy stage 2 is an improvement in low rpm performance compared with std despite massively higher flow.

The Bad Boy 2, the most serious of them (largest most potential to surge comp wheel) and the one least likely to boost nicely, will sit on 20psi at 1600rpm with AFRS much better than 20:1 (ie, safely sustain while towing without smoke). Test ANY other wastegated turbo on a 4.2L diesel that can hold 30psi to the fuel cut and see what happens under 2000rpm (it wont be pretty)

Also, mucking around and doing your own DIY is really fun. And, many people have time more than they have $ so they try something cheap - fine. The case is difefrent for everyone.

I'm at the point where I just want the right turbo on my truck and simply enjoy it.
 
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My computer is down atm. But I do have a detailed tuning guide with pics also. It basically just explains the why and what to do. As you may know what you want, but now how to go about it.
 
im suprised other parts of the world are not trying to import atebs fuel mods, like were trying to get what we do not have here ,but to date the extreme v/b is still the over seas slow boat. for now. curious about the ve ,cfm numbers ? still stock ? you say you hate the front entry style intake . i thought it was best with the front mount cooler design (old supra junkyard find )being a shorter run and one less 90 *.you guys over there have a surplus of manifold designs to use at your disposal ? contacts please ,im sure they could sell a bunch ,i would have bought one intead of designing one, (oxygen tank ,from the srap yard) and yes i know its a gamble with the under 300 dollar turbo but if the numbers work the numbers work.

It just personal preference why I dislike the front entry design. You can seriously just do all mods to the pump yourself. There is absolutely no need to import these things.
 
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What's the dynamat for? Got a noisey intercooler?
 
pulling the turbo just to see if i can isolate were the power is actually coming from, plus the chinese turbo has a larger exhaust. surge issues were contolled by a blowoff valve controlled by a throtle body for vacume. the pump is set to supply fuel for 6000 rpm (if needed ). this is my daily driver (sea level -2000+ feet daily). i would love to see the badboy 2 ,anyone in the vancouver area have one,what turbo is adam running . to bad i could not get a demo turbo off of you to compliment atebs tuning, now that would be the ticket i bet.
 
Adam is running an older grunter model gturbo
G's new turbos apparently are more responsive.
 
yes basically a butterfly just before the intake in line with the throttle cable (jack sprocket therory) . and ya i hear you hammo,to blind funny .i was told when building my manifold to be carefull on the tapperred plenium intakes ( at least on the entrance anyways if your running big boost) . and the local turbo guy i have been useing seems to know his stuff (more than 1 bonniville record).
 
Do you have any specs on your intake as far as diameter length and stuff? did you do a bell mouth and how far off the floor did you space it? I am thinking of doing a plenum for my 3B as the stock one has nothing and is really just 4 runners. Pics would be awesome. This is one of the few threads in the last while thats got some good potential.
 
yes basically a butterfly just before the intake in line with the throttle cable (jack sprocket therory) . and ya i hear you hammo,to blind funny .i was told when building my manifold to be carefull on the tapperred plenium intakes ( at least on the entrance anyways if your running big boost) . and the local turbo guy i have been useing seems to know his stuff (more than 1 bonniville record).

Post a shot of this prado intake up and your 81s intake.

This thread is useless without pictures!:flipoff2:
 
hi guys i am not trying to pissed any one, nor i am trying to proved that i am not alone in this world, know how to tune any diesel engine. just to let you know beside, greame -there is lot of other people out there have very good knowledge but just keep quiet about it.i apology if i ever step on any one toes. but every one has it own tuning & desire for power where comparison is of no points.if greame think of him self as top of the world tunner & no one come close, then let it be.i have been doing turbocharging in the 80`s before i came to canada so i believe i have done enough till today & not new on these subject.
 
hi guys i am not trying to pissed any one, nor i am trying to proved that i am not alone in this world, know how to tune any diesel engine. just to let you know beside, greame -there is lot of other people out there have very good knowledge but just keep quiet about it.i apology if i ever step on any one toes. but every one has it own tuning & desire for power where comparison is of no points.if greame think of him self as top of the world tunner & no one come close, then let it be.i have been doing turbocharging in the 80`s before i came to canada so i believe i have done enough till today & not new on these subject.

Where? Look at all the garrett range, all previous high flowed ct26's etc. NONE of them can match these turbo's. for 1 simple reason. They are designed and built for this engine. It's always been give and take for low down and high end boost. There is no compromise. New extended tip fin design impellers. All you guys are doing, is using the pump as a band aid. Using high end boost turbo's and dumping crap loads of fuel down low to over come the lack of response/spool. You can do that if you like, there's no rules. But to date, no other turbo I have seen matches it. Boost is boost! 25psi vs 25psi is going to be the same hp (apart from other factors). Noone is saying you can't beat the top end numbers. But everyone is saying the low end response is fantastic, while still maintaining high boost levels.


I want to know exactly what they do to these pumps? And dyno figures/afr's/egt's. 0-60mph times.
 

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