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Discussion Starter · #1 ·
Hi guys, I thought someone may be interested in this build I am currently completing. It is a Lancer (Australia) with the 4g69 engine.

After considerable research I could not find anyone who built a top-mount turbo setup, I may be wrong...but having built hundreds of turbo setups in my previous business/workshop from bottom-mount/side-mount/rear-mount etc, I find top-mount has many benefits.

Was run and driven for the first time yesterday. It is not yet tuned and am awaiting several components for the final tune. I'll provide some details regarding that once tune is completed and if there is interest on this forum.

Some specs:
- Tubular manifold with pyramid collector, with pulsing of cylinders in a clockwise 1-3-4-2 order. Ceramic coated
- GT2871R with .86 housing. Internal wastegate has been ported
- 2.5" downpipe with wideband, y-pipe and QTP cutout on the downpipe section
- Greddy 600x300x75mm intercooler that I cut-and-shut down to 220mm height (fits under crash support and plenty of flow potential for this setup)
- Sump removed, cleaned and drain welded-in. I don't trust bolted-through drain setups

The turbo intake pipe is just temporary in the photo during R&D. Currently installed a 7psi wastegate of an R32 GTR while getting baselines, then intend to up the boost to get into the bottom-end of the efficiency range of the turbo.
 

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Looks like you did a great job! Very nice! Will you be dyno tuning this? I’d be interested to see what you get for power out of it.
 

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Discussion Starter · #4 ·
Looks like you did a great job! Very nice! Will you be dyno tuning this? I’d be interested to see what you get for power out of it.
I will almost certainly run it on the dyno mainly for a baseline to use as reference for future changes. I wish i had dyno'd the car before turboing for a real before-after
 

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Discussion Starter · #5 ·
Looks nice. But it's not the first top mount 4G69, there's one in my friend's Lancer.

Probably about 350hp potential out of that setup though, and it should live in boost lol. Lots of bottom and mid range
I would've been very surprised if it hadn't been done. Certainly not chasing 350hp in this first stage, but the components are capable of it if we decide to take it to the next level
 

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Discussion Starter · #7 ·
Remove your EGR is a huge tip though. Cylinder 4 runs hot with it still installed. My friend cracked 2 pistons in cylinder 4 before measuring it and finding a heat difference.

Doing any motor build?
I have a real dislike for EGR's due to the carbon buildup throught the intake however I am surprised he cracked 2 pistons as a result of the EGR, as they only operate in closed-loop mode and not during WOT.

I'm not suggesting this is your friends case, but very often you can see piston/valve damage on the cylinder closest to the throttle body if using a 5th injector type setup, as fuel distribution is not equal. Again, I'm not saying this is the case of your friend, mostly I'm discussing this as someone else may find this discussion useful.

In our case, we are using multi-port progressive water-methanol injection in collaboration with other ecu and fuelling systems (yet to be finalised/published). I am new to the 4g69 platform, but my experience with 4g63 motors/tuning is that they respond very positively to timing advance. Short of running E85, the water/meth will afford significantly lower IAT's & EGT's together with knock control.

At this stage I don't know if we will build the engine. It does have 150,000 kms, and the tested compression and engine vacuum is a lower than it should be (again, modern engines with EGR's tend to suffer bad exhaust guide wear and pitted valve seats - I see this weekly on engine rebuilds).

When I pulled the sump to weld-in the turbo drain I noticed the rods are very thin which is typical of a modern well engineered efficient engine design. This is mainly a potential issue at big power levels and at boost onset at very low revs, and this turbo setup - whether it be due to the large engine capacity, the efficient turbo, the turbo manifold....or a combination of all - this thing just wants to produce positive manifold pressure immediately. It is extremely responsive. A set of rods, pistons, head studs would be beneficial at some stage
 

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How are you going to run the water/methanol system: direct port or before the throttle body?
 

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2009 GS Turbo. 2006+2007 GT
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His EGR may have been leaking some. But whatever the cause, it's a common issue when these see forced induction and removing the valve fixes it.

Stock rods are very thin, but what broke first for me were the rod bearings. I got unlucky I guess. My turbo also likes to be at 6psi already by 2200rpm if I let it (16g 10.5t twin scroll, tubular equal length manifold)
 

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Discussion Starter · #11 ·
How are you going to run the water/methanol system: direct port or before the throttle body?
Within the intake manifold itself, after throttle body. This provides more equal distribution, and as we will be using it part of the overall tune, it is quite important
 

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Discussion Starter · #12 ·
Sabertooth - yes the TS TD05-16g range are excellent turbo, particularly the HRA version for lowish boost. Excellent response, plentiful upgrades, great power.

I am removing the intake mani at the moment to install the water/meth system, and will be bypassing the EGR at the same time.
 

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Discussion Starter · #13 · (Edited)
looking good, love the manifold.
Thank you, I appreciate your comment. Yes, it certainly seems to be working as well as expected.

Intake manifold has been cut-open, all the carbon has been flushed-out and some porting has been done. A 5-degree cut into the runners was done, then the bellmouths reprofiled. The entrance into the plenum has been significantly reshaped too. No polishing was done as it is not necessary, and Also as we will be spraying water/meth I wanted to avoid surface tension

The EGR was weld-filled on the inside of the plenum (you'll see the original EGR port in the "before" photo will no longer be there in the "after" photo) then the outside of the port was ground-down to access the EGR port and was then welded from the outside also.
 

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Discussion Starter · #14 ·
Testing the 2 x 255cc methanol sprayers. They are positioned in a way that one jet is directly exactly centred between cyl 1 & 2, and the other jet centred between 3 & 4. The manifold intake runners are knife-edged and ported

[URL="https://youtu.be/yVD9-W5M0Hs[/URL]
 

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Testing the 2 x 255cc methanol sprayers. They are positioned in a way that one jet is directly exactly centred between cyl 1 & 2, and the other jet centred between 3 & 4. The manifold intake runners are knife-edged and ported

[URL="https://youtu.be/yVD9-W5M0Hs[/URL]
Is there a reason you didn’t do a direct-port system with 4 nozzles? That way you wouldn’t have to worry about balance between cylinders.
 

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Discussion Starter · #16 ·
Is there a reason you didn’t do a direct-port system with 4 nozzles? That way you wouldn’t have to worry about balance between cylinders.
Fair question. The only reason is budgetary constraints. Having said that, the methanol sprayers are located precisely between the bridges of the cylinders, and the ports are knife edged. The spray pattern is very good. I am always pragmatically concerned about many aspects of a build, but I am very confident the cylinder balance will be within 5%-8%....which is well within discrepancies between (fuel) injectors in the majority of cars
 

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Optimally you'd spray before the throttle body, as far back post intercooler as you can. You want the spray to go from atomized to evaporated, cooling the air charge as much as is possible. You'd also see proper IAT sensor data if far enough back, and it would be easier to tune, and the most consistent between cylinders
 

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Discussion Starter · #18 · (Edited)
Optimally you'd spray before the throttle body, as far back post intercooler as you can. You want the spray to go from atomized to evaporated, cooling the air charge as much as is possible. You'd also see proper IAT sensor data if far enough back, and it would be easier to tune, and the most consistent between cylinders
With respect, I disagree. The charge air is not hot enough (post IC) to evaporate until it enters the combustion chamber. Water with methanol will not flash-off at 60º Celsius for a long long time, even 75º Celsius. The mixture enters the combustion chamber as an atomised mist which is what gives its anti-detonation properties.

When spraying pre-throttle body, whilst effective, the liquid cannot change direction as quickly as the air, so generally you will see richer mixtures on the far end of the intake maniold and leaner towards the throttle Body. I've tested this on hundrreds of cars over the years and every engine designation/combination is different. There are so many ways of utilising water/meth. One of my cars I use a water-only 60cc jet pre-intercooler to avoid heat soak and a progressive 300cc pre-TB and it works great....horses for courses
 

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I need to find a place near me that would port and polish an intake manifold like that. Splitting the runners isn't as optimal as 1 per, but sounds like it should do the trick. Placement will be the key. Great work so far.
 

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Discussion Starter · #20 · (Edited)
I need to find a place near me that would port and polish an intake manifold like that. Splitting the runners isn't as optimal as 1 per, but sounds like it should do the trick. Placement will be the key. Great work so far.
I appreciate the feedback of everyone involved here...constructive and respectful criticism will create a great knowledge resource for everyone.

Originally this setup was to use just one methanol jet (i´ll upload a photo) but my concern was; the #4 runner being so close to the TB, and the fact the plenum is not tapered, Hence increasing probability of distribution issues.

The more I think about it, I have a niggling issue with individual jets in each intake runner. The issue I have is pooling due to the cyclic nature of the engine. In comparison to a fuel injector (which pulses) the jets are just spraying at 100% duty cycle. Admittedly it is under boost and high revs, but pooling will still occur.

The pulses that occur within the intake manifold (1-3-4-2) should help excite the water-meth (if sprayed in the plenum) within the plenum itself and be drawn into each cylinder very evenly with less pooling than jets in each individual runner.
 

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