M50 Manifold Install Complete! All working! Tips inside

[SergeK]

Hey guys. Just fixed the vac leak, and heres my rating on the m50 mod.

I give it a 7 outta 10. Here are the reasons.

Pros -
Pulls like a train past 4500 RPM
Makes the engine louder and deeper sounding
Looks cooler than M52 mani.

Cons -
VERY hard install
Good amount of torque loss
General pain in the ass.

The first install took almost 9 hours. I bought the kit from E36M3E, the kit was well put together, but the instructions were made for an S52. So there were very small discrepancies.

After thee first install, there was HUGE vacuum leak. Wouldnt hold idle at all. It was like a Cammed LS1 with very Lobey cams.

Today, i took the manifold off, and dug around. I found a Rotted Vac line at the very bottom. It connects to the bottom of the Crank Case Vent Tank. I replaced the line, put everything back together, and presto.

I fired up the car once, Stall. Twice, Stall. Third, Stall. Fourth time, I fired it up but revved it to about 1500 rpms and left it there for 15 seconds. I let go and the idle evened out. I screamed with joy 'YES!' I let it run for about 2-3 minutes to adjust. Shut it down.

Then went out for the test drive. I let the car warm up to normal operating temp. Then at a red light, i floored it. It hesitated a little. So i let off at about 4000 rpms in first. I jumped on I95. I left the car in 3rd gear (automatic) going about 50-55 mph until i found an opening. I found one...

I put the gear into second, and slammed the pedal. THE CAR FRIGGIN LEAPT! Before i knew it i had to switch into third and it kept pulling and pulling althe way up to redline. I was amazed. It just kept going and going...

Then i tried a few launches. Id powerbrake up til about 1500rpm then let loose. It would launch a little bit slower and it wouldnt spin the tires, but at the top of first gear, above 4k rpm, thats when it really leapt and started pulling. Overall, im satisifed...

TIPS

-Label all vacuum hoses as youre dismantleing the manifold.
-PAY ATTENTION! Take pictures, notes, whatever! I made the mistake of not doing any of those, and it took us 4-5 hours to figure out the vac piping.
-Take your time, be patient.
-While youre down there, clean your ICV. I sprayed it with carb cleaner and shook it around a little, thats all it took.
-Read the isntall instructions a few times, maybe even 10, so you get familiarized.


Up next? SOFTWARE, Shark Injector FTW!

[SergeK]

BUMP

One thing. Idle is still a LITTLE rough, but im sure it will straighten out within a few days.

[LuvMy328is]

Congrats on the upgrade! I hope you found my Official M50 Upgrade Thread to be useful As far as the idle, with no software it will take 2-3 days for the car to be COMPLETELY normal again. You should also notice a performance increase after a few weeks. The adaptation of our cars will learn the new setup and the car should gradually improve. Good job and enjoy
~Phil

[SergeK]

Ive already noticed a huge increase past 4500 rpm, and i mean HUGE. I couldnt get the grin off my face. And the louder, throatier sound it puts out is amazing. I ran an S500 earlier today, got two runs... i got him on the first one only because i was getting onto I95 really fast, and he saw me so he tried to play catch up.

second time, we rolled from about 20-25 mph, and i was pulling on him until bottom of third (autotragic)

[SergeK]

bump

[E36M3E]

Glad to hear you got your kit installed without too much trouble...the first time I did the install it took me 2 days. So I'd say 8-9 hours is about right with the kit. I do them in about 3-4 now.

Sorry the instructions are not perfect for the 328...like I said I had never done it before...I knew it was close. maybe you could fill me in on the defficiencies of the DIY? email me with a list maybe?

do you have the M50 fuel rail cover? I am working on a solution to that this week.


Thank you for your bussiness.

Eric

[aztecboi]

i did a swap but have no idle..it stalls competely


help>>>>

[boomersooner523]

im looking into doing this swap and ive read enough about the problems and it sounds like u have a vaccum leak or a bad hose or perhaps a loose connection somewhere in the new hoses you used for the install

[boomersooner523]

also did you use the throttle body from the original m50 or did you use the one that came stock on your car?? ive always wondered this!

so would i be better off buying the m50 with the throttle body attached or just the manifole and use my throttle body?

[LuvMy328is]

Def sounds like a vacuum leak. Did you reuse the TB gasket, buy a new one. or did the old one get reused? That could be the problem.
~Phil

[happycamper]

but u drive an automatic

[mpwr ren rebel]

Def sounds like a vacuum leak. Did you reuse the TB gasket, buy a new one. or did the old one get reused? That could be the problem.
~Phil

If he bought the kit from Eric, then he should have used the new TB gasket. I'm hoping to swap on a m50 within the next month. Just depends how much I can save this month.

[boomersooner523]

Def sounds like a vacuum leak. Did you reuse the TB gasket, buy a new one. or did the old one get reused? That could be the problem.
~Phil

whats you opinion on reusing the throttle body that cam on the m50 originally? should i keep mine and just forget the one on the m50?

[E36M3E]

i did a swap but have no idle..it stalls competely


help>>>>

you have a vacuum leak or your ICV is not connected electronically or it is jammed...the last 2 would set codes. the vacuum leak would set a code if it was large enough to cause your O2 sensors to reach their trimming limits.

also did you use the throttle body from the original m50 or did you use the one that came stock on your car?? ive always wondered this!

so would i be better off buying the m50 with the throttle body attached or just the manifole and use my throttle body?

you don't need the M50 TB. you just need my custom TB seal or the plate and 2 OE seals.

E

[LuvMy328is]

If he bought the kit from Eric, then he should have used the new TB gasket. I'm hoping to swap on a m50 within the next month. Just depends how much I can save this month.

whats you opinion on reusing the throttle body that cam on the m50 originally? should i keep mine and just forget the one on the m50?

See Eric's previous response BTW, his custom seal is sweet!
~Phil

[psilocybe]

Currently in my car, i have the stock m52 intake and tb
I bought an m50 intake & tb for $40 shipped.

Since i have the tb from the m50, should i just use that? or stick with the m52.

[Maxi]

good job.

[boomersooner523]

you have a vacuum leak or your ICV is not connected electronically or it is jammed...the last 2 would set codes. the vacuum leak would set a code if it was large enough to cause your O2 sensors to reach their trimming limits.



you don't need the M50 TB. you just need my custom TB seal or the plate and 2 OE seals.

E

thanks your probably the guy that i needed to talk to about that...just to let you know i will be purchaseing your kit here in a month or two when i get the money!

[LuvMy328is]

Currently in my car, i have the stock m52 intake and tb
I bought an m50 intake & tb for $40 shipped.

Since i have the tb from the m50, should i just use that? or stick with the m52.

Keep your M52 TB
~Phil

[psilocybe]

will do thanks

on another note, anyone need an m50 tb, i have one CHEAP

[bmxludwig]

Keep your M52 TB
~Phil

Is the m50 tb any different from the m52 tb? I know the m52's have asc and all that jazz but is the actual tb any different? Sure would be nice to not have to deal with a custom seal or two factory gaskets with the m52 tb...

[E36M3E]

Is the m50 tb any different from the m52 tb? I know the m52's have asc and all that jazz but is the actual tb any different? Sure would be nice to not have to deal with a custom seal or two factory gaskets with the m52 tb...

the only difference between the 2 is the M50 TB has no seal gland and the M52 has a seal gland.

why would anyone wana go to the trouble and the expense of swapping the TBs when for 20 bucks you can buy the proper seal for the M52 TB and the M50 manifold application and be done with it?

E

[NHbmw325I]

asc is tied into a separate throttle body that bolts to the "normal" throttle body, and a lot of 325's have asc also.

[BMW&PorscheDude]

If you have a rough idle after doing this mod, chances are you have a vacuum leak. You just have to be careful and take your time, and make sure everything is connected properly and snug. My idle smoothed out right away on my 328i, and I was impressed immediately at how quiet and smooth it ran, because everyone says it will idle rough for some time afterwards.

Also, for you guys who have ASC, you will want to do the ASC delete mod before doing this M50 manifold swap. The ASC throttle body is very restrictive and you will be much happier without it (except for the light on your dash which you will come to ignore or cover up).

Regarding the super secret throttle body gasket, you can just use two stock gaskets. You cut one as nice and neat as you can with a brand new utility knife blade, pressing down on a block of wood as you work your way carefully around the gasket. Once you have the cut gasket in two rings, you stuff one into the throttle body and the other into the M50 manifold. The full size gasket goes in between the two "halved" gaskets. I even used my original gasket and the one that came with my used M50 manifold, so I didn't even have to buy any. Yes, I'm a cheapo, but did I mention how perfectly it idles? Absolutley no problem here. I did spring for new port gaskets though. Don't buy them from the stealer, cuz they want like $20 buck each (x6). Buy them online or from a supporting vendor for about $2 each.

Good luck and enjoy the upgrade!!!

[bmxludwig]

the only difference between the 2 is the M50 TB has no seal gland and the M52 has a seal gland.

why would anyone wana go to the trouble and the expense of swapping the TBs when for 20 bucks you can buy the proper seal for the M52 TB and the M50 manifold application and be done with it?

E

I don't understand the expense and trouble of using the factory obd1 m50 tb with the obd1 manifold I guess? It would eliminate all sealing issues if you were to use the obd1 manifold with its factory throttle body. Instead of going to the junk yard and just pulling the manifold, you pull the mani and the tb right?