[neilvan]

Originally Posted by ornicar

My idea is trying to fit two or maybe three elbows in serial (from the TB) with a straight pipe to the air box. I hope that it will allow to have a correct alignment.

The last photo is a N52 Elbow fitting on a N54 TB.

I shortened the nose of the N54 TB. Its a little bit longer than the N52 one but the stock intake piping fits on and within the body (this is on my brothers 328 w/ 3 stage mani)

[ornicar]

Originally Posted by neilvan

I shortened the nose of the N54 TB. Its a little bit longer than the N52 one but the stock intake piping fits on and within the body (this is on my brothers 328 w/ 3 stage mani)

I had thought to doing it too!

The question is will the pipe still fit when on the N54 manifold (which have a different angle)? maybe the second elbow may help to obtain the correct angle to fit the pipe to the airbox. what do you think?

[neilvan]

Originally Posted by ornicar

I had thought to doing it too!

The question is will the pipe still fit when on the N54 manifold (which have a different angle)? maybe the second elbow may help to obtain the correct angle to fit the pipe to the airbox. what do you think?

I mean youre not wrong (this is the n54 MANIFOLD thread lol). The N54 mani comes out at a much different angle and looking at the pic posted the custom one for the N54 mani is muchh shorter. both have 2x 45 deg angles but the stock pipe is much longer(has that straight section)

[72GMC]

Originally Posted by Biginboca

BTW I appreciate all info and corrections anyone can add to this thread! As you can see I’m still working on compiling all the info but in the end I hope this thread becomes the one place everyone can find answers they need regarding this swap.

Nice thread Big.
And thanks to all the other contributors.

[Jros]

Originally Posted by neilvan

I mean youre not wrong (this is the n54 MANIFOLD thread lol). The N54 mani comes out at a much different angle and looking at the pic posted the custom one for the N54 mani is muchh shorter. both have 2x 45 deg angles but the stock pipe is much longer(has that straight section)

Do we know how long is the pipe needed? If the maximum angle of bend is around 45 degrees i was thinking about using one of these bendable silicon hoses.
I bet this in conjunction with the stock N52 throttle body short elbow would do the trick


https://www.ebay.it/itm/ULTRAFLEX-IN...-127634-2357-0

[Papa Popov]

Appreciate the detailed breakdown and how-to. Made me decide against the swap to preserve the low-end torque from the 3SIM.

A bit off topic, but do you have any dynos to back up the 7-9hp gain from a 2cat delete? I've seen a lot of numbers thrown around for this mod but never seen anything to back 'em up. Been debating if I should chop mine for a while now and would definitely pull the trigger for 7-9hp.

[Biginboca]

Originally Posted by Papa Popov

Appreciate the detailed breakdown and how-to. Made me decide against the swap to preserve the low-end torque from the 3SIM.

A bit off topic, but do you have any dynos to back up the 7-9hp gain from a 2cat delete? I've seen a lot of numbers thrown around for this mod but never seen anything to back 'em up. Been debating if I should chop mine for a while now and would definitely pull the trigger for 7-9hp.

They were posted on the forum years ago. I don’t have them saved but if you do some digging maybe you can find them.

[Biginboca]

I have almost finished the tutorial and have updated the throttle body info in the parts list. Thank you everyone for any corrections to keep it accurate and simple!

[Biginboca]

Originally Posted by Papa Popov

Appreciate the detailed breakdown and how-to. Made me decide against the swap to preserve the low-end torque from the 3SIM.

A bit off topic, but do you have any dynos to back up the 7-9hp gain from a 2cat delete? I've seen a lot of numbers thrown around for this mod but never seen anything to back 'em up. Been debating if I should chop mine for a while now and would definitely pull the trigger for 7-9hp.

Here you go, just googled and it came right up as the first hit:

https://www.e90post.com/forums/showthread.php?t=703329

[stilesg57]

Great write-up, thank you! A great resource to the board.

The Catch-22 of the 3SIM is that right after you've spent $600 for new DISAs is when you're both the most financially committed to it...and the most interested in going to a manifold that doesn't have them

[Biginboca]

Originally Posted by stilesg57

Great write-up, thank you! A great resource to the board.

The Catch-22 of the 3SIM is that right after you've spent $600 for new DISAs is when you're both the most financially committed to it...and the most interested in going to a manifold that doesn't have them

Thanks! And yeah that is so true! When I had the 3 stage I bought it with used DISA’s and had no idea what I was getting into at the time lol

[Jros]

Did MILVS and n54 manifold together today. I installed the manifold without any sleeve (lazy) just letting it fall down a bit, lining it with the edge of the head, and i have perfect fuel trims.

Loaded my stageFP tune and car runs perfectly. I miss the low end torque some to be honest, but it drives so smooth and pulls to 7500 rpm now.

It sounds different too, higher pitch and more refined than the 3sim.

I haven't done an adaption reset though, i think the car could get even better given some time.

[ornicar]

Originally Posted by Jros

Did MILVS and n54 manifold together today. I installed the manifold without any sleeve (lazy) just letting it fall down a bit, lining it with the edge of the head, and i have perfect fuel trims.

Loaded my stageFP tune and car runs perfectly. I miss the low end torque some to be honest, but it drives so smooth and pulls to 7500 rpm now.

It sounds different too, higher pitch and more refined than the 3sim.

I haven't done an adaption reset though, i think the car could get even better given some time.

Great!

Keep us inform please if it become better in few days or weeks!

Thanks

[Jros]

Update: for now i feel like I lost power, particularly mid-hi around 5k rpm.

Engine MAF reading curve peaks now around 7100 rpm, keep in mind mine is a 2.5 liter and i don't know if a 3 liter would peak higher or lower in the rpm range than mine with this mod.

Mine peaked at 6500 before with 3SIM, but the air flow at peak was about the same, that reinforces my hypothesis that i lost power.

Gonna ask Bob at StageFP if it could be the tune. Considering i had done MILVS too i was expecting gains only over 4k rpm versus 3SIM and no MILVS.

Gonna update again when i have got an answer.

[Noir]

Great write up as always!
I appreciate you hooking me up way back when with the finished product.
With the adjustments that thing sits on the head like it should — no play/nice and snug. 🥳

[AdrianE36]

Originally Posted by Biginboca

N54 Intake Manifold Swap Parts Shopping List:



Amazon Parts for Connecting Airbox to Throttle Body



Hiwowsport 90 Degree Elbow 4-Ply Thickness 5mm High Performance Coupler Silicone Hose for Auto with 2PCS T-Bolt Clamp Black Color(ID:3.5"(89mm)) https://www.amazon.com/dp/B074V6K6LH...ing=UTF8&psc=1

Upgr8 Universal 4-Ply High Performance 45 Degree Elbow Coupler Silicone Hose (3.25"(83MM), Blue) https://www.amazon.com/dp/B00CB22I6Y...ing=UTF8&psc=1

HiwowSport 6'' Length Straight Alloy Aluminum Intake Tube Aluminum Hose Adapter OD:3.5''(89MM) https://www.amazon.com/dp/B07K2WG83F...ing=UTF8&psc=1

About the 45 degree elbow and the intake tube: the tube seems too big for the elbow to fit onto it. Any tips on getting it to fit?

[Biginboca]

Originally Posted by AdrianE36

About the 45 degree elbow and the intake tube: the tube seems too big for the elbow to fit onto it. Any tips on getting it to fit?

So I sprayed some silicone lubricant on the parts and was able to get the elbow over the tube. If that doesn’t work for you maybe try heating the silicone some to soften it.

One of the swaps I did with my buddy recently he just mated the 2 silicones directly and left the aluminum tube out.



His comment was “I actually skipped the aluminum tube and just put one silicone piece in the other. Then I put a metal clamp around it to reinforce it from collapsing under vacuum.”

So I felt the aluminum tube was needed to keep the silicone from collapsing but he seems to not be having any issues without it.

[AdrianE36]

Originally Posted by Biginboca

So I sprayed some silicone lubricant on the parts and was able to get the elbow over the tube. If that doesn’t work for you maybe try heating the silicone some to soften it.

One of the swaps I did with my buddy recently he just mated the 2 silicones directly and left the aluminum tube out.



His comment was “I actually skipped the aluminum tube and just put one silicone piece in the other. Then I put a metal clamp around it to reinforce it from collapsing under vacuum.”

So I felt the aluminum tube was needed to keep the silicone from collapsing but he seems to not be having any issues without it.

Thanks for the tip! I'll try your method when I get home today.

[shimstack]

Thanks for putting all the info together Biginboca , I'm about to start buying parts for this.

Presumably the car will run fine on the stock ECU map prior to loading the tune?

[Biginboca]

Originally Posted by shimstack

Thanks for putting all the info together Biginboca , I'm about to start buying parts for this.

Presumably the car will run fine on the stock ECU map prior to loading the tune?

I’m sure it will run without the tune just won’t be optimized.

[shimstack]

Originally Posted by Biginboca

I’m sure it will run without the tune just won’t be optimized.

Thanks. Just need it to run to get through emissions inspection on stock software every two years.

Mani and TB on the way.

[Biginboca]

Originally Posted by shimstack

Thanks. Just need it to run to get through emissions inspection on stock software every two years.

Mani and TB on the way.

Awesome!

And I just added the Airbox connection part of my tutorial post so now it’s all done…