1HD-T Intake Manifold Modifications (1 Viewer)

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Hey Graeme, pm sent.
 
Bigboy and Graeme, do you have any pics you can share of the plenum mods? I understand completely if you dont wish to share something that may be still under development.

That ebay add is the first I've seen of anyone producing the plenums for sale. That's not to say there aren't lots of weird and wonderfull plenums and designs running around. I'm not developing anything (plenum nor cooler) for sale. And i dont think graeme is either. If you want 1 in aus. You usually make your own. Do your research well and record results. If you make a mistake, do it again until your happy with the results. Trial and error.
 
ok so if we do as graeme suggests and weld a bit of 4" tube to the top of the manifold were is the best place to put the inlet.

as per the pic attached are we better off coming in from the end where the green is

or are we better of say coming in from the side inline with say no2 and no5 pistons as per the red trying to give an even supply of air to each of the intakes or will this cause to much air turbulances.

what is everyone thoughts.

 
The manifold that enters from the end is that way to accommodate the front mount inter cooler piping im guessing. Many of those plenums of that design are in really cramped engine bays and dont have any other choice from where to enter the manifold. I run a top mount intercooler so when I do a manifold I will be designing it around a top entry as I feel it is easier to design one that flow even to the end cylinders. Now that is not to say the end ones cant be designed to flow well to the end cylinders, but it takes a bit more thought and patience in the build. As mentioned here, a large plenum aids in that as well, so there are many ways you could do it. Here is mine on my 3B. No manifold for a while im afraid. If im to do any serous work on my engine it will be on the turbos as its the best bang for the buck time wise. Core is a 12x12x4. Will be changed to a 12x12x3 eventually, after the house reno. Erm that photo is before I cut my hood for the scoop, sorry. Runs 68% efficient after 15min boost at 20-25 psi 70-90kmh. It has no fan on it as there is no room yet.
intercooler top.webp
intercooler top.webp
 
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hate to ask but i have done extreme flow ,egt testing on 3 completly different front entrance enlarged style intake mod on the 1hdt for well over a year . i would not listen to bigboy on untried intake mod results until he tries it with an inter cooler or takes it up a pratical hill period . so if anybody has at least a couple weeks experience with these qualifacations lets hear it ,other wise its hear say bs therory, which is healthy and where this mod is at, just because i have had excellent results does not mean it cannot be better . but please why would people bs about something they do not have experience in try and brainwash people with bs . bigboy you sound dangerously convincing with your wta therorys so all you need to do is dial in your wta then you can start your own thread ,not understanding why your side tracking the intake mod thread (maybe your problems should be talked through we are listening). i have 30,000 km on my manifold mods with over 25 psi boost throughout and the first to admit ,it has not been pretty. so what you say about the big manifold boy.
 
hate to ask but i have done extreme flow ,egt testing on 3 completly different front entrance enlarged style intake mod on the 1hdt for well over a year . i would not listen to bigboy on untried intake mod results until he tries it with an inter cooler or takes it up a pratical hill period . so if anybody has at least a couple weeks experience with these qualifacations lets hear it ,other wise its hear say bs therory, which is healthy and where this mod is at, just because i have had excellent results does not mean it cannot be better . but please why would people bs about something they do not have experience in try and brainwash people with bs . bigboy you sound dangerously convincing with your wta therorys so all you need to do is dial in your wta then you can start your own thread ,not understanding why your side tracking the intake mod thread (maybe your problems should be talked through we are listening). i have 30,000 km on my manifold mods with over 25 psi boost throughout and the first to admit ,it has not been pretty. so what you say about the big manifold boy.

Your a serious tosser wrong way. I have no idea wtf your on about. You try and twist everything around. How many times do I have to say it. I wouldn't go a plenum this large for normal use. What does a cooler have to do with the plenum mod? I have nearly all my data on my plenum. You seem to know everything. And with your attitude why would I share anyway.
 
Your a serious tosser wrong way. I have no idea wtf your on about. You try and twist everything around. How many times do I have to say it. I wouldn't go a plenum this large for normal use. What does a cooler have to do with the plenum mod? I have nearly all my data on my plenum. You seem to know everything. And with your attitude why would I share anyway.

Please refrain from personal insults. The beautiful thing about living where you do is there are quite a few diesel Toyota forums. Do feel free to remove yourself to any one of them permanently if you intend to be rude.
 
Core is a 12x12x4. Will be changed to a 12x12x3 eventually, after the house reno. Erm that photo is before I cut my hood for the scoop, sorry. Runs 68% efficient after 15min boost at 20-25 psi 70-90kmh. It has no fan on it as there is no room yet.

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is this one custom made .. I'm just looking for one like yours for Tencha ..
 
The manifold that enters from the end is that way to accommodate the front mount inter cooler piping im guessing. Many of those plenums of that design are in really cramped engine bays and dont have any other choice from where to enter the manifold.

Exactly. I like a tidy engine bay and hate having to remove a heap of things on top of the engine to get to things. The log manifold mod and FMIC achieves that. And, the only reason I chose 4" tube was because I simply wanted to minimise ve differences along the length of the manifold when feeding from the front.

I haven't done ANY scientific tests on the intake manifold mods. Im not selling them and have only ever suggested it to people as somethings that I would do (which doesn't make it gospel truth). My thought process on the matter is as simple as this. "the intake manifold like poo, lets improve it". Anecdotal evidence by the few that have done it (even with 3" is positive. But I don't have a skerrick of data.

Big Boy is 4500km's away from me on opposite side of country, I will probably never see his setup. He is also a customer that paid for a turbo custom built to an end goal like any other customer. So if he says its good bad or other then it is what it is. I only mention that because the impression I get is that it seems Wrongway thinks we are in some joint effort to promote products or something. That couldn't be farther from the truth. He is trying a heap of his own ideas for himself and commenting on them on these forums, thats all it is. I only know a bit about the setup because I needed to know to spec the turbo, and I provide advice as requested.
 
ok i do not feel good about what i said to you bigboy ,sorry. this thread i thought was a intake mod shareing thread (IS IT WORTH AND WHATS THE GAINS AND WHAT THE DOWN FALLS AND WHAT DESIGNS ARE THERE ). well i got one and i feel that for a super simple mod that there is no down falls only gains in basically every thing that can be affected . i only did this mod so i could dump more fuel in ,i did not think i would run smoother sound better and run cooler. to bad i could not do it in stock form for comparison. i think if someone starts makeing these things they should have an entrance option 10 o clock (wta) 2 o clock and front mount(that is if there is no difference or performance flaws that might come from either) i think my front entrance is the worst design really. and no i am not looking to make a liveing or looking for bragging rights i just want a reliable truck that can drive in the fast . about the only thing i can add to this thread is the build . i just cut the top of my manifold off put a 4 inch piece of pipe on it mark it cut it put on weld it cap it extend your linkage riser weld on a cable stop on top for the cable,cut a 3 inch whole for your own entrance of choice and weld your entrance pipe on .
 
is this one custom made .. I'm just looking for one like yours for Tencha ..

Hey Tap.It is a standard ebay special. http://www.ebay.ca/itm/190329710509?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2648 I cut one tank off and turned it 180degrees and welded it back on. I also added an internal baffle if you will to direct the air flow in the core more evenly. I did add some 1/2 round aluminum stock tube onto the transitions for the passages to cut down on turbulence. Im going to switch it to a 3 inch core eventually

Here is were I cut the tank off. I would have cut about 1cm further up from the weld and it would have made welding on the 1/2 round stock easier.
008 (Medium)cut.webp

Here is a good pic of what your getting with a nice high quality 100$ ebay core. I straightened out the fins with needle nose pliers. I was skeptical, but It will hold 20lbs pressure for 10 min after all my work was done, so its sealed. Note the welds fixing the core (from factory) and the giant flat spots that will cause turbulence for air entering the runners
011 (Medium)weld.webp

I got some 1/2 inch alum tube and cut it in half
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015 (Medium)cut tube.webp


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I then deburred it and buffed it and squished it in a vice length wise to fit it perfectly on the flat area not to impinge on the runners. It also took ona more cone shape. I dont have a pic of the cone shape apparently, but this is close to what it looked liek.
013 (Medium)cresent.webp

I then Tacked it on the flat areas in between the runner like this.
012 (Medium)improve flow.webp
013 (Medium)cresent.webp
012 (Medium)improve flow.webp
 
I then took some flat stock aluminum and bent it on my vice in an "s" shape and trimmed it to fit in the tank and line up with 1/2 of the passages to catch 1/2 of the intake air like this. Sorry I lost my own pics, but this is what I modeled it off of. I dont weld aluminum, but i pad a local welder 100 bucks and called it done. The improvements are to even flow across the core for efficiency and internal mods to cut back-pressure. Flame on.

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baffel 2.webp
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baffel 2.webp
 
ok i do not feel good about what i said to you bigboy ,sorry. this thread i thought was a intake mod shareing thread (IS IT WORTH AND WHATS THE GAINS AND WHAT THE DOWN FALLS AND WHAT DESIGNS ARE THERE ). well i got one and i feel that for a super simple mod that there is no down falls only gains in basically every thing that can be affected . i only did this mod so i could dump more fuel in ,i did not think i would run smoother sound better and run cooler. to bad i could not do it in stock form for comparison. i think if someone starts makeing these things they should have an entrance option 10 o clock (wta) 2 o clock and front mount(that is if there is no difference or performance flaws that might come from either) i think my front entrance is the worst design really. and no i am not looking to make a liveing or looking for bragging rights i just want a reliable truck that can drive in the fast . about the only thing i can add to this thread is the build . i just cut the top of my manifold off put a 4 inch piece of pipe on it mark it cut it put on weld it cap it extend your linkage riser weld on a cable stop on top for the cable,cut a 3 inch whole for your own entrance of choice and weld your entrance pipe on .

It's all good. My apologies also. I have the results for my truck. But, I did the turbo and other mods at the same time. So now have to put the standard manifold back on to compare between only those 2. So until then I think it's useless for me to say what the mod alone does. But the final result with all these mods together is super impressive so far.


I think a 3" pipe is perfect. I personally just dislike the front entry. I'd rather something more symmetrical that feeds all the cylinders evenly and matches the angle of the runners that face up (no extra corners).


Noones selling anything or promoting. graeme doesnt have to for his turbos. They are that good! Customers just choose to share their thoughts, (as like me) they are very very impressed. We just want good mods.


My plenum has some lag (always knew it would due to the size). But we do things very differently down here. I could set the pump up to dump heaps of pre boost fuel to overcome the lag (easy). But I would get laughed at. We have acceptable and unexceptable levels of smoke. A puff off the line and a haze under boost is fine. Smoking like a train is not. This is why by running below ambient temps (increasing mass) allows me to dump more fuel with out the smoke.
 
mine is on the smokey side of the scale thats for sure,especially with the lowerred stall speed lockup. and yes i am so jealous of gbentinks gturbo , and your guys wholesale tranies. i had better control of my egts with the 4 inch for sure. i did not notice any difference in low rev spool up between the 3 inch and 4 inch but it sure sounded nicer with the 4 inch. by saying 4 inch mine is actually just a standard small size oxygen tank (scrap dealer find)that happens to be exactly the same size as the 1hdt manifold, i just changed the taperred end to be squared. thats it, gerg you should be making these . maybe you can find a smaller one for the 4 banger ,that could be a conversation piece in the works parking lot.
 
Nice work Greg.

I think there's a small tradeoff with the curved entry to the cores. With the curved engine pressure drop across the cooler will be lower, but the less turbulent flow will drop heat transfer slightly.

Personally I like the extra flow and lower pressure drop more than the extra turbulence and would also do what you have done in the same situation.
 
Ahh thanks Doug. It was fun making it. I dont know why cores don't come made this way as it wouldn't really take much more of an investment and you will get a superior product. As for manufacturing manifolds. If you buy me a tig and teach me how to use it, I'll make one manifold per year. Well... if I have time:p
 
I then took some flat stock aluminum and bent it on my vice in an "s" shape and trimmed it to fit in the tank and line up with 1/2 of the passages to catch 1/2 of the intake air like this. Sorry I lost my own pics, but this is what I modeled it off of. I dont weld aluminum, but i pad a local welder 100 bucks and called it done. The improvements are to even flow across the core for efficiency and internal mods to cut back-pressure. Flame on.

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AWESOME .. !

I have the same exact core .. that's why I was asking .. I'll see if I could found someone that's willing to weld it for me ...
 

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