W123 na manifold on 82 300sd (faster bottom acceleration/ adding IC)
 

Hello all, I am new to this forum, but have been ghosting a number of mercedes diesel forums over the last 2 years to gather information on improving engine performance.
This is really a shoutout to ForcedInduction, tho currently banned on most mbz forums, but your older posts have really done a wonder on my om617 and i can proudly say i know the top end of the thing really well.

Ok enough kissing a$$, here is the sitch:

I have a boost gauge, pyrometer, and still the stock t3.

-in a few posts Forced has claimed the w123 na manifold will fit his 617 setup, tho he opts to use the w115 long runner, but he does have a different turbo, Will the w123 intake manifold fit over the stock t3 if clocked correctly?

Others have said no on similar models, some have said it will, has anyone actually tested it over a stock t3, NOT KKK turbo?

I ordered one off of ebay, almost mint condition came in, only $60 free shipping and i will use it no matter the headache.

If it will not fit over the stock t3 ( it really looks like it might, but i need to drive the car to school till the weekend, so i cant comfortably swap) WHAT are my options, (modify exhaust manifold, replace/ modify turbo, etc)?

Money is no issue, I am searching for the SIMPLEST and MOST RELIABLE options.


Current setup, if it makes any difference:
-Real cold air intake, oversized k&n filter for GM v8s, ran from turbo to under bumper with 3 inch piping.
-Air to Air IC is mounted front (28"x8"), minimal bumper chopping, pipes are 2.25 aluminum with NO SILICON elbows, all bends are aluminum to reduce lag.
-EGR delete
-pyro/ boost gauge
-engine is sparkly clean, in tip top maintained state with ~300k miles, only trany is in question
-amg 8.0x17 rare monoblocks with no spacers
-replaced holy muffler with thrush glasspacks and cool exhaust tip (im in San Francisco so i cant run it too loud)
-remote locking system with new vac pump and wiring to avoid confusion with the pumps solenoids

possible solution
 

uppon closer inspection, it looks as though the manifold will not clear the t3, perhaps a holset 25, 35, or 40 like the one in this video would be an easy swap and a rather inexpensive solution:

Mercedes 300D holseth hx40g - YouTube

or ebay 25
eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

Thanks for the quick response! I keep worrying that the thing wont fit, and the more i try to eybeball and ruler calculate the less it looks like it would, but man that would be an easy solution. Did you ever run a na w123 setup such as this that you could comment on performance wise?

A little water in the engine does good and cleans, and my filter is right beneath the headlight, but up against the bumper with its curvature, so im not worried about puddles, and dont drive the beast in rain very often (my car is also not lowered, and the rims push it up higher).
To tell you the truth, k & N is not my favorite, but fram has the worst reputation of filtration companies other than STP.
I shouldnt be arguing with an experienced pro like yourself tho, and may revert to running it behind the headlight again.

What fuel injectors do you use on your om617 btw Forced? its getting time to replace mine after all these miles.

the na w123 manifold is overlapping my t3 turbo by ~1/4 inch, what should i Do? what are my simple, most reliable options?

-modify exhaust manifold/ flange angle?
-turbo with different shape?
-anyone have a w115 long runner manifold they want to sell?

Need some help here
 

So i ordered a hx35 because the general consensus is that it will spool a little later than the garett t3, but get the job done, and will most likely be a noticible upgrade since im still running the original untouched 30 year old turbo. I will turn up the fuel pump to max, and eventually have the local diesel tuning shop upgrade my 5mm mw plungers (its a jump to an unnecessary 8mm, but i will run it a little starved at that point).

I noticed a youtube video with a mbz running a hx40 with na w123 manifold like mine, and it seemed to clear just fine, figured the hx35 will too.

I will start taking pictures once everything arrives and post my results, any ideas what im gonna do with the turbo oil supply line? i picked up an extra one at pray and pull, but it looks like im gonna have to tubing bend it or have a shop chop/flare and connect stainless hose.

Anyone done anything similar that they could comment on, any info will be greatly appreciated!

...and yes forced i will have the air filter on a right angle behind the headlight so it wont be a cold water intake.

should be perfect
 

My 82 300sd is a rocket right now from 0-20mph, and 60- 95mph. My problem is a massive lack of power between those ranges, I realize it is because of my bowden cable setting, but no matter how i set it i have to compromise power in one of those ranges. the hx 35 should be perfect under load in that range and thus a viable solution to the problem. Look at this bad boy

In car video w116 with Holset hx35 turbo - YouTube

btw
 

he does have a video posted of his car drag racing and kicking a volvo/ vw's a$$.
83 300d with 7.5mm ip. Hx40turbo and race tranny - YouTube

Another thing, your nitpicking/ missing the point of my question, of course the tubo is going to spool later than the t3, but Realize i am paying return shipping if the thing doesnt clear the n/a long runner manifold, as this is essential to getting the turbo to spool up more quickly.

All i am looking for is a viable solution to getting that n/a manifold on the car and clearing whatever turbo will fit without compromising power.

THe more important question to answer as well is what am i going to do about the oil supply line? is the flare/stainless braid something that i can do at home or the local auto shop can do? I have a spare metal one from pray and pull, can i simply heat it up and bend it with a tubing bender? what is best from your experience?

lol I thought he tried both because half his youtube vids are hx, half hy. what a rube.

Im counting on it. My purposes are drifting, show, and outrunning Daly city fuzz back into my san francisco county. Im not running 0-60s, but 60s -xxx at 100% throttle. THese cars are too heavy for 0-60 with tiny engines, acceleration is a dead loss, im hoping the long runner intake will help.

He was using an hx40 which is definitely too big, an hx35 would do better with adequate fueling, correct?


Dont underestimate my appreciation for your posts, im naturally blunt, i was just honing you in on the topics i need answered most. Your past posts with the ~banned next to them have made my ride what it is today.


I get the preceding fitting references, but please elaborate on this part, im no mechanic like yourself.

I see now, (from that hx40 burnout video you were dissing as turbo617 about making his car slower) how he got it to clear the n/a manifold, he put a clamp on 4" exhaust coupling in the middle of the turbo to push the tall part forward. I have the option of doing this on the hx35 i ordered, any potential issues?

I read on yet another forum that he hydrolocked his engine with an even lower than mine cold water intake, in a suburban environment though, an extreme punishment for experimentation.

THats exactly the terminology i was looking for, it looks like in the vid below that he used a v-clamp 4" exhaust coupling added between the turbine and bearing housings. It might just work with propper support. cant see it till the last few seconds, and hard to make out his exact rig.

Mercedes 300D holseth hx40g - YouTube


Thanks for the oil line restrictor info, where would you recomend online to order the pieces i cant get at my hardware store?

Just to get a better idea of the housings scale, if an hx40 is 16-18, and the hx35 i ordered is for sure 12 on my paperwork, how big is my ai garrett t3's?

According to my tach and boost gauge, the garrett starts spooling around 1500- 1800 rpm, full boost at 10psi by about 2200-2500; are you saying the hx35 wont start, mid, or finish at 3000rpm?

Also im getting a barage of faster spooling tactics from the nissan forums, like building back pressure, wrapping the exhaust, etc. Any specific ones for diesel i should know about?

The new hx35 also wont clear the n/a manifold, do you have an old short runner to sell me forced, or any ideas on things i can do to make a turbo clear the w123 one? I contacted the guy with the modified short runner one Dieselboy740 with the hydrolocked engine, last i heard in january he still had it.

Thanks for the very informative thread on oil line fitting/ pressure reducers btw, will definately help as i start ordering. I also dont really have a wrapping fever, just looking for anything to make the holset spool just a little sooner.

cool
 

okay, so the adapter/ spacer is out of the picture, cause even the stock turbo only gets another 2" before it hits some metal line right next to the fender, the hx35 would currently be about half inch clearance from that line as well, my only option would be to drop the turbo ~2".

Your angle idea is perfect in this regard, but will anyone who welds professionally touch a high heat exhaust manifold at the risk of their reputation? I can easily grab another exhaust manifold at pick and pull for < $40 and chop at it. for the 2" extension down, can i use regular steel or do i need to find cast iron, or what material is the manifold made of anyways?

I followed your tutorial on turning up the full load today, 19mm and 9mm lock nuts. The middle one seemed to be a 14mm and i tightened it all the way with my fingers, tightened it all back up, replaced the pump side cover, will fill with fresh synthetic 1/2 quart tomorrow.

I took the oil filter housing off to get to it, dont have a new gasket though, and the old one looks pretty good still, just gonna use some rejuvinatiion goop on it, nothing that will chunk off into the housing though. Im like a child on christmas eve now, cant wait till church is over tomorrow,

So you mean the limiter controls 20hp from stock, or i get an additional 20 from removing it?

Also, what material is safe to have welded onto a now ~1000 *f exhaust manifold, possibly 1200 in the future? what are exhaust manifolds made out of, just ordinary steel? If i just drop the flange down ~2", both turbos would have no trouble clearing the w123 manifold.

Luckily the gasket sealer on the old oil filter housing gasket holds under full load with the oil pressure, i did make it surgically clean. I could only see a little smoke in the following cars' headlights because it was night when i test drove, but people kept changing lanes to avoid being behind me so it must have been a decent amount:)

waste gate adusting tomorrow, im gonna run it at 14psi for the time being

update
 

So i found this guy on a blog online who just restored a w115 and fit it with a turbo i believe, but he had a bunch of extra parts in his garage including the rare coveted 1975 manifold.
So im getting it for $100 if there are no cracks, i believe that includes shipping, hes de-greasing it tomorrow to double check before paypallin it.
Ive been browsing ricer forums for opinions on the hx35, i know gas and diesel are different, but they maintain it spools a little before 3k rpm, just as you said.
I am affraid of outright removing the rack limiter/ full load adjustment assEmbly, lest i experience oscilating idle, where CAN I PURCHASE THAT upgraded gold anodized kit?
Oil return line on the Holset, WILL IT LINE UP WITH THE TURBO FROM YOUR OWN experiences?
Oil supply line on the holset- now that i have the new manifold, it should just BOLT ON WITHOUT INTERFERING with little to no bending, IS THE PRESSURE GOING TO BE CORRECT WITH THE STOCK ORIFICE/ REDUCER?

update
 

I have been quite busy with school, traveled for spring break so i have not been able to work on the merc. However my w115 intake na manifold did finally come in so i will install it on the next sunny saturday.

I also ordered and received a manual boost controller because my stock t3 turbo wont exceed 10psi no matter how much i adjust it. It never has put out less than 8psi, and will not pass 10 psi. Is a boost controller a smart way to go, or do i seriously need to worry about spiking?

The car is hard to start when cold, even if it is not cold outside. If i put my foot on the gas while i crank it starts right up, maybe an air leak? The injectors have not been changed or messed with for about 7 years now, the first two look like they leak ever so slowly (diesel residue around where they screw on) time for new injectors?

update
 

Forced, you sir are truly an experienced mechanic. Replaced all 5 of my bosch glow plugs with 5 new ****ty autolites that came with the car and it fired up and even idled right, warmed up faster, and the lag from p to D on the shifter was much less. I saved the bosch ones to clean and test later when i have more time.

My coworker got the temp sensor and boost pressure hookup to thread on the new manifold with fittings and teflon tape (will it melt under engine heat?) and i painted it with some cool green engine enamel i bought on spring break in oregon with no sales tax! I just got a canopy for my driveway so i can work rain or shine too.

I clamped the waste gate hose as well and it still wont pass 10psi, turbo problem? I will be installing the hx35 soon anyways but is there anything i can do to the garrett to put out more air?

I will look at trading my hx35w for something smaller, i bought it at the steal of under $290 new with shipping (i assume its a rebuild by E||USA) but its genuine holset based on Holset tactics for identifying fakes on their website. I also bought it because i eventually plan on installing a 90s E model diesel engine in the car and want something worth transferring over in the turbo department.

Is there anything i can do to my turbo in the mean time to dislodge that internal spring? I will have the exhaust manifold and turbo off the car this weekend as i install the w115 intake manifold and intercooler piping.

My uncle has redneck tapping and lubrication strategies that often work on engine components that otherwise would require a lot of work to disasseble or replace, if you could point me in the right direction to hit or lubricate without damaging turbo parts? (parts like recoil pull starts and other spring loaded parts)

Disappeared for a bit; now im back to tuning my diesel.
I finally got time to work on my 300sd, graduating in January with a BS in Information Systems. My benz has been running great with a w115 manifold, and my mechanic found the fuel pump was 24 degrees off timing and fixed it- car idles much better now. I just picked up a a stock t3 from the wrecking yard which will hopefully hit 15psi because my old turb0 has lots of shaft play.

I traded the off brand holset hx35 i purchased to a couple of rednecks for a brand new real branded hx30; i might install it someday when i play with fittings and do more research.

question- I have seen what looks like to be an auxillary fuel pump in your engine bay Forcedinduction, I just got a fuel pump that says it works on diesels- Do you run one, how is the best way to connect it, any benefits?


I will take pics and post them.

cool, i saw your external fuel filter thread and have decided to perform your surgery on my vehicle. That was the part i thought was an auxilliary diesel pump.
I got a diesel fuel pump from my grandpa that he once intended to put on his 300d wagon. It is a quality model as far as they go from the google search i did, i can post the info when i get home. Due you recommend installing such a pump to enhance or smooth throttle response in altitudes or on inclines? How will it affect performance? bad Idea for this car? setup inline, on which part of the fuel system?

k, il save it till i get an m pump. My newly installed t3 is barely pushing 11psi with the wastegate nut fully tightened, I really want more boost. I ordered some fittings for my new hx30 after brushing up on your orifice thread.

So just to recap- Im not buying any orifice parts, just gonna cut a quarter20 bolt and drill a ~.05" hole in it & put it inline before my addon oil pressure gauge--> keep trying different sized bolt holes till it is inline with holset pressure specs. Will a standard psi gauge from my hardware store be ok?

My hx30 does not have a wastegate built in, How much psi do you think it will make? If more than 15psi, how do i go about limiting boost pressure with no internal wastegate?

Maybe something like this clamped to the egr port on my exhaust manifold:
44MM External Turbo Exhaust Manifold Wastegate 8Psi V-Band Civic B16 B18 Integra | eBay

why so low? i somehow got the idea that it could pull off 15psi easily. what happens if it is installed with no wastegate?

side by side the hx30 & garette t3 are similar in size. Its much smaller than the hx35 i previously had. so your saying that theoretically its still too big to spool up to full potential on the om617 & its almost impossible to do the engine massive damage by not having a waste gate?

btw my old t3 that barely hit 9psi with wastegate fully tightened - i took the cover off of the back of the wastegate and the metal flange/seal was cracked & twisted inside- simple fix?