New here - 300E Turbo on LPG - need info

[BAD300]

Hi all, was reading a doc' on here showing step-by-step instructions on removing 3.0L Head on W124 300E. Was so impressed (thanks to ) by effort I just ahd to join

I have recently purchased an 87' 300E that has been well, kinda modded

It has however suffered @ the hands of the previous owner/builder. Let's say I got it in the nick of time before he well & truely crucified it!

I need some parts & advice so, here it is. I'll wack up just enough pics to show you the car & that I am serious. As you will quickly see, this previous owner has spent alot of $$$$ & love/time on this. It has forgies & MSD stand alone for fuel/spark. Also, it runs on constant LPG via mixer!
I intend to finish & fix uo the balls-up so to speak.

Right now I am in process of removing engine block & taking it to my builder for resurrection. It's hard to believe this engine has done only 4k since full rebuild, although it was done some years ago & has sat & well, is stuffed now! Heat/corrosion etc played huge part as did bad tune imo.

First part, I am after is a custom exhaust manifold. The spaghetti/spider type with equal runners. Either stainless or steampipe. It currently has modified orig' 2-piece manifold. Not my favourite

Turbo is currently TO3 highflowed to TO4 but, looks as though it has succumbed to same fate as poor engine. So, if I get another turbo, what are good performance options?

I am turbo savvy but admit, right now to all, not Mercedes savvy & am willing to learn from ones that know. Any advice is very appreciated.

I know & have read of stock M103 engines with twin turboes etc. I am interesterd in this engine seeing the full potential of bullet-proof bottom end taking way more boost than 7-10psi. Like, 20-25 @ least.

Here's a pic of the similar manifold I'm after. Although, this one is for the 24V engine, not the 12V I have:

Car Pics:

 

[d w124]

Hi there and welcome to the forum.That manifold on the pic is custom built,so i`ll be hard to find one for sale.Not 100% sure, but i think the early 300-24 shares the same manifold with the m103.I`m sorry to say this but the turbo wizard,just past the way few days ago(MAY HE REST IN PEACE).By the way,lovely car

 

[grober]

Your best bet honestly is to locate a MOSSELMAN twin turbo kit for sale and refurb that. I don't quite get the complexity of adding an alternative fuel [LPG] unless its to exploit its antiknock qualities. I would think it would make mapping/programming the fuel demands /ignition advance of the engine very difficult indeed. Your best bet for a custom exhaust manifold would be to trawl some of the USA turbo enthusiast sites on the internet. The conversion on the surface looks quite professionally done- I assume it had an adequate intercooler etc. Doesn't seem to be much extra engine compartment ventilation for all that extra heat generated under the bonnet. As has been said one of our most knowledgeable members on turbocharging has just died very sadly . this is a good basic principles book but slightly out of date now if you havn't read it.

 

[BAD300]

My respects to the recently deceased member mentioned!

Thanks for welcome guys & tips

The LPG conversion was performed previously by seller. I just want to fix it up. Yes grober, the work is very professional & using neat FM intercooler. Alot of time/$$$$ spent by previous owner. I believe engine had a miriad of failures due manly to ignorant mechanics that worked on it inc' previous owner. There has been corossion/heat/detonation & water damage to engine. I even suspect that the engine builder may have retarded timing, as you would do with boosting petrol, instead of advancing as is necessary with boosted LPG. The anti-detonation/higher octane properties of LPG were the main benefits of conversion I think. Also, LPG is way less than half price of cheapest petrol here in Australia plus, we were offered substantial rebate from our Gov as an insentive to convert.

Entire engine is being rebuilt now

Thanks again guys!

 

[grober]

You may also want to take a look at this recent thread from a forum member in the USA on his twin turbo set up. http://www.mbclub.co.uk/forums/mbclub-projects/70857-300ce-widebody.html

 

[BAD300]

You may also want to take a look at this recent thread from a forum member in the USA on his twin turbo set up. http://www.mbclub.co.uk/forums/mbclub-projects/70857-300ce-widebody.html

tbh, I'm not interested in the twin set up. I have looked @ sequential Jap set ups years back. 1 small, 1 larger turbo. I have read that most revert to 1 large single turbo & get the ext manifold sorted amongst other things in order to lower turbo lag & increase boost @ lower revs. Even supercharged cars have tossed the SC for a large turbo done properly. Plenty of opinions on this I've read. A guy on peachparts forum is running a GT45 on a stock 3.0L 24V engine pulling 650HP @ present with 1000cc injectors. Nuts! There is no way I would be using stock internals with that type of set up

Ultimaely, I just want to fix this current set up that has been butchered so badly by previous owner. Could make you cry. All the $$$$ & time spent for nothing.

I am keen in looking @ all angles though & thanks for info. Much apreciated

 

[khimani_mohiki]

I thought LPG and forced induction didnt go together as the mixer works on manifold vacuum to draw the LPG through. Is your mixer positioned before or after the turbo?

 

[nick.ged]

if you want a big single turbo manifold, with screemer pipe, contact roman @ turbobandits, they are approx 700 gbp. std 103 bottom end will take 500 bhp no problems.

 

[BAD300]

if you want a big single turbo manifold, with screemer pipe, contact roman @ turbobandits, they are approx 700 gbp. std 103 bottom end will take 500 bhp no problems.

Manifolds are presently being fabricated. Both inlet & exhaust. I have finally come up with correct build & car will hopefully be completed within 2 months. Maybe sooner? Alot of research & $$$$ already but I will see project through. bee discussing with performance guys over on that foorum where Roman is a member & yeah am aware of the 4 cars he has built using stock M103 & 104 engines. 1 using 35 turbo & another a 45. Mad I will add some info in a post soon. I am going with a GT3540 custom build turbo with Billet comp wheel, ceramic bearings & .63 A/R exh housing. Steampipe exh manifold with external wastegate. Will further info below on separate post.

I thought LPG and forced induction didnt go together as the mixer works on manifold vacuum to draw the LPG through. Is your mixer positioned before or after the turbo?

Nup! LPG seems to scare people too easy. Down here in Australia the set ups appear to be better than the US. I can't speak for Europe? Have had great success with title-holding cars running mixers on V8's, outdoing injection.

Fact is. LPG can deliver excellent performance if set up right. You have to guarantee flow volume to cylinders

 

[BAD300]

Basically. I located a low nklm excellent M103 engine & now block is being tapped for oil return fitting. Engine will remain stock, unopened!

Here is a quick run down of what I have purchased & work done so far. Not much work but will be accelerating very quickly from now & over next month.

Very sound engine replacement
Larger FMIC
New Behl Radiator & hoses etc
New engine mounts
New Gearbox mount
Rebuilt Trans with shift kit & 2300rpm stall convertor
Billet GT3540R .63 A/R
custom Plenum Inlet Manifold
Custom Steampipe exhaust manifold with external wastegate
Microtech MT8 ECU
3" turbo back mandrel exhaust

 

[NISFAN]

Hello Bad300, good work on the conversion so far, looks very un Mercedes like. I like it

If you need any custom parts done like manifolds, etc, call Rob at RIPS. He is in Rotorua NZ.

Regarding the Turbo, now I don't know much about LPG, so might be wrong here, but if it were petrol, a .63 ex housing is going to be too small for that size engine. You would experience lot's of surge at initial boost. For help on this turbo and similar applications, join some of the Nissan Skyline forums in OZ. The standard Nissan has a 2.5 or 2.6 litre straight six (RB25 and RB26), but there are what are known as RB30 conversions which are 3 litre. They do have 24v heads, and if you can fit a 24v head I would recommned you do that.

Regarding an un opened engine, I would consider new pistons atleast. Need to lower the CR, and forged pistons are not a lot of dosh these days, even custom made if not off the shelf for your car.

My avatar is same set up as my engine. Skyline, RB26 with HKS T04Z. Just over 700bhp.

Good luck and keep posting.

 

[kth286]

if you want a big single turbo manifold, with screemer pipe, contact roman @ turbobandits, they are approx 700 gbp. std 103 bottom end will take 500 bhp no problems.

Not for long without lowering the compression ratio.

 

[BAD300]

Hello Bad300, good work on the conversion so far, looks very un Mercedes like. I like it

If you need any custom parts done like manifolds, etc, call Rob at RIPS. He is in Rotorua NZ.

Regarding the Turbo, now I don't know much about LPG, so might be wrong here, but if it were petrol, a .63 ex housing is going to be too small for that size engine. You would experience lot's of surge at initial boost. For help on this turbo and similar applications, join some of the Nissan Skyline forums in OZ. The standard Nissan has a 2.5 or 2.6 litre straight six (RB25 and RB26), but there are what are known as RB30 conversions which are 3 litre. They do have 24v heads, and if you can fit a 24v head I would recommned you do that.

Regarding an un opened engine, I would consider new pistons atleast. Need to lower the CR, and forged pistons are not a lot of dosh these days, even custom made if not off the shelf for your car.

My avatar is same set up as my engine. Skyline, RB26 with HKS T04Z. Just over 700bhp.

Good luck and keep posting.

Thanks NISFAN,

yeah I have been researching alot of the Silvia, Supra etc forums I am actually having a specialist workshop do the work. All fabricating inc' manifolds to dyno. One of the best I've found. Melbourne VIC is pretty good for custom work. Concerning the rebild of engine. No need believe me. The cars engine seller built had forgies, you name it.....BANG! You don't need to pull engine down unless you want over 650hp. It's all in the tune & how you set everything up. 450whp is easy without even stand alone but of course it is better to go with one for software mapping. I was initially concerned about surge but I believe the NISSAN & SUPRA heads flow better so maybe they ave the surge probs & need larger A/R? Workshop reckons using a larger FMIC takes care of the surge probs. Also. I'm only using the 40 trim turbine with the smaller housing a/r not the normal 72!

Btw.....I have a set of forgies to suit for sale. Only time I'd pull engine down is if I wanted to race it & needed to fit multi-layer head gasket then I'd wack the forgies in. Have you viewed Roman's (Pumpish) beasts he's built? 4 stock M103's & M104's pulling from 450whp to 650. Thrashes them. Something I'll never do. All he broke was the front flex plate Ask RYBCC. He'll confirm it.

There seems to be a golden rule with Mercs....'if it aint broken, don't fix it'....that's why even engine builders shy away from rebuilding Mercs without very good cause.

Not for long without lowering the compression ratio.

Hi kth286,

I have alot of info to put up concerning this build. Even members on your forum like like RYBCC & others you may or may not know like Pumpish, JayRash just to name a few will be able to confirm you can run higher compression with no problems @ all. It's all about correct AFM's & set up etc etc. There is a whole swag of things to consider but easily done if you know how to

P.S. I can't do a project thread yet bugger it! haha

 

[NISFAN]

CR on a standard M103 is only 9.2 to start with, quite low for an NA engine. This is OK for low to medium boost levels, provided hi octane fuel is used. I would say you could probably go for up to 10psi reasonably safely, but don't know how susceptable the M103 is to knock. 24V head would be a safer bet.

You were looking to go much higher than this, so that is deffo low CR territory.

 

[BAD300]

CR on a standard M103 is only 9.2 to start with, quite low for an NA engine. This is OK for low to medium boost levels, provided hi octane fuel is used. I would say you could probably go for up to 10psi reasonably safely, but don't know how susceptable the M103 is to knock. 24V head would be a safer bet.

You were looking to go much higher than this, so that is deffo low CR territory.

your right on the button & you would think so yes but, LPG has higher octane properties though & can run higher boost. Pumpish runs 20-25psi on his stock M104 using a GT45. 98 Pump fuel. I'm serious! These engines are quite tough but he may be using a multi-layer head gasket. I'm not sure. Guys run 15psi easily on these stock comp engines on pump gas.

That doesn't mean I would race it round a track @ high revs & boost as heat would take it's toll yes! But for street use. How much of the time would you be pushing high boost & revs? Not alot really. 1/2 throttle would see you up round 10psi. Workshop guy uses an XR6T as his daily driver & 1/4 throttle he is getting 6psi with same turbo as mine will be except with 1.06 a/r housing

thanks for input I really appreciate others with same interest man. Great discussions

 

[BAD300]

Decided to raise the boost in increments when we, eventually do get to tune car Initially do a run @ 10psi using a 45 external wastegate then @ 15psi @ see how she fairs & what hp we can achieve @ this boost. As I've said before, hp will be down due to small turbine housing but the trade off is quicker low down response so I can live with that I won't be running a BOV as the auto's stalled @ 2300-2500rpm so unlike manual gear changes where you would definitely run a BOV, gear change will be pretty much instantaneous & BOV in this case would be for the **** effect only. Back pressure will be negligible & the large wastegate will do that job well. Also the larger comp wheel ensure large volume of airflow & counter the back pressure anyway. All in the set up @ this stage.

Also @ this stage I think I'll call it a day @ 15psi for reliability purposes more than anything. The LPG will work in my advantage in this area with it's higher octane ability however, this hp will be a big enough shock I think for the stock car including running gear, brakes, suspension per se.

The MT8 has to be made up especially & will be a few weeks wait bugger it. Hopefully there is enough to be done in the meantime with fabrication anyway?

 

[BAD300]

P.S. I may still run a BOV. Plumbed back though but awaiting workshops call