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1990 300ce 24v
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Ok well I've been on here saying I was going to sell my car, but now I'm reconsidering and am seriously thinking about a supercharger for the CE. If I'm patient and do most of the work then I believe I can do the whole thing for under $1500. Yes $1500, call BS if you want but I'm serious. I'm looking at putting the HP up to around 300-320 and the torgue right there too. I just need a little info to get off right...

1)What is the output of the injectors for a '90 300ce? 19 ft/lb, 24, 30? I couldn't find a figure anywhere!

2)These run at a 10:1 compression. I'll be running roughly 5-6 psi giving a total of roughly 14.1. Premium detonates around 13.1, but if done correctly it can probably run 8 psi through it, but I won't. I figure an intercooler will help this significantly!

3)Have any of you decreased your compression ratios below 10:1 maybe around 9.5.1? I think I can do this by getting some thicker gaskets and making the chambers a little larger. This would put the overall compression at 13.4 at 6 psi. I think for every .025" increase it will drop compression by 1 (refering to the gasket). I believe you can get copper ones made that are virtually "blow-out" proof. I'll give up some HP for the torque! Any other ideas? Convex cylinders lower compression pistons, etc.?

4)I'm contemplating a few ways to run the charger
a) (best, most work and $$$$) mounting a second pulley on the crankshaft, extending the fan 2" closer to the radiator by means of the axel, cutting part of the shroud and connecting directly with the supercharger b) (very feasible just rerouting could get tricky) rerouting the current belt off the air pump into a pulley, onto the SC, down under the existing idler pulley, then back on track. c) (probably the worst idea, and probably won't be efficient) mount a second pulley onto the existing air pump and then connect directly to the SC. Any idea which one would work best?

If I do it then I'll be using an Eatom M90 supercharger and making custom mounts off the passenger side of the engine near the air pump, and bracing it off the exhaus manifold studs (brace isn't too important but I need it to be strong at the front where the pulley tension will be).

I said I'd use an intercooler to prevent early detonation. I'm not sure if I would take it on top of the block (heat shield b/t) and use the existing air intake to rerout air onto the intercooler, or have the intercooler run a) down low in the front air dam, or extend the fan and put it b/t the fan and the engine.

Intake would either be front mounted coming in from where the front tow hook area it, or it would be cowl inducted up near where the wiper is.

I know I don't have all the kinks worked out and there are still alot of things I have to install and consider first but if anybody has any comments, can offer assistance, or can possibly provide certain "materials" or references to custom fabicators that would be great. I'd love to create something that is great for power so that anybody who wants to can do it. Its a shame a car this gorgeous isn't more fun!
 

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300cePutterMcGavin - 5/11/2005 1:49 AM

Ok well I've been on here saying I was going to sell my car, but now I'm reconsidering and am seriously thinking about a supercharger for the CE. If I'm patient and do most of the work then I believe I can do the whole thing for under $1500. Yes $1500, call BS if you want but I'm serious. I'm looking at putting the HP up to around 300-320 and the torgue right there too. I just need a little info to get off right...

1)What is the output of the injectors for a '90 300ce? 19 ft/lb, 24, 30? I couldn't find a figure anywhere!

You will be able to get plenty of fuel via adjusting the EHA, so no worries.

2)These run at a 10:1 compression. I'll be running roughly 5-6 psi giving a total of roughly 14.1. Premium detonates around 13.1, but if done correctly it can probably run 8 psi through it, but I won't. I figure an intercooler will help this significantly!

I'd say forgo the intercooler and run alchol injection...far easier to install and you can pick up models that are boost dependant/adjutable.

3)Have any of you decreased your compression ratios below 10:1 maybe around 9.5.1? I think I can do this by getting some thicker gaskets and making the chambers a little larger. This would put the overall compression at 13.4 at 6 psi. I think for every .025" increase it will drop compression by 1 (refering to the gasket). I believe you can get copper ones made that are virtually "blow-out" proof. I'll give up some HP for the torque! Any other ideas? Convex cylinders lower compression pistons, etc.?

Copper gaskets will give you dis-similar metal fun w/ your head. There is a new style of gasket, multi density something or other.. They are apprantly the way to go at this point.

4)I'm contemplating a few ways to run the charger
a) (best, most work and $$$$) mounting a second pulley on the crankshaft, extending the fan 2" closer to the radiator by means of the axel, cutting part of the shroud and connecting directly with the supercharger b) (very feasible just rerouting could get tricky) rerouting the current belt off the air pump into a pulley, onto the SC, down under the existing idler pulley, then back on track. c) (probably the worst idea, and probably won't be efficient) mount a second pulley onto the existing air pump and then connect directly to the SC. Any idea which one would work best?

I'd say forget the stock fan and install a dual flex a lite system. SuperchargedSEC and Satish w/ his M120 SEC both run the system w/ Excellent results.

If I do it then I'll be using an Eatom M90 supercharger and making custom mounts off the passenger side of the engine near the air pump, and bracing it off the exhaus manifold studs (brace isn't too important but I need it to be strong at the front where the pulley tension will be).

I'd still make that braket fairly stout. You don't want that blower shifting at all in relation to the engine.

I said I'd use an intercooler to prevent early detonation. I'm not sure if I would take it on top of the block (heat shield b/t) and use the existing air intake to rerout air onto the intercooler, or have the intercooler run a) down low in the front air dam, or extend the fan and put it b/t the fan and the engine.

Intake would either be front mounted coming in from where the front tow hook area it, or it would be cowl inducted up near where the wiper is.

Cold air off the front of these cars should not be an issue. Or other set ups I have seen run a large K&N w/ a hear shield towards the motor/exhaust.

I know I don't have all the kinks worked out and there are still alot of things I have to install and consider first but if anybody has any comments, can offer assistance, or can possibly provide certain "materials" or references to custom fabicators that would be great. I'd love to create something that is great for power so that anybody who wants to can do it. Its a shame a car this gorgeous isn't more fun!
I'd suggest you put a fresh head on your car..w/ the added combustion chamber pressure you'll want your top in in first rate shape.

Where are you getting your M90?? I am fairly familar w/ the unit as our Regal GS is equipped w/ one. My strongest warning if you are buying a used unit is you need to be Sure the oil was changed/tended to. A lot of people overlook the S/C'er oil and it causes a Lot of premature wear in the unit. They really need the fluid changed every 15-30K w/ top up's in b/w.

W/ your Eaton M90 you should look at the DUB (dial ur boost) set up. Makes swapping pulleys Easy:)

Sounds like a fun project, Enjoy!!!

Jonathan
 

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1990 300ce 24v
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Discussion Starter #3
Wow Jonathan awesome advice, it definately has me thinking about some things in a different light. I've begun pricing everything out and if I do the work (less machine shop labor, and certain custom fabrication) then I definately think I can keep my cost around the $1500 mark. I do however have a couple quick questions for you.

-Well to answer the whole head work issue, I don't know if I'll replace it withe a fresh head. I've talked to numerous MB places and have looked all over the forums (here and elsewhere) and I haven't found any indication of a cracked head. Apparently these things are bulletproof. I think I'll probably just have it reconditioned and milled where necessary. If I get into it and find problems then I'll do otherwise. If anything needs replaced while I have the heads off then it will be done. Timing chain, valve guides, seals, etc.

-That alcohol injection seems like the definate way to go. An intercooler setup would have been a PITA to get right. My only concern with it however is the way this car is set up. I'd like some boost to help with the low end, but at the same time when I'm on the highway doing 80 I'm taching at about 3900 RPM...I'm just worried I'll be killing the alcohol/water mix rather quickly, and it goes "boom". I've contemplated getting a higher diff. and maybe changing out the drive gears to make them longer but that might still be an issue.

-You mentioned something about a "multi-density...." gasket. I can't find anything for the CE with this. MB doesn't offer a thicker one and doesn't know who does. Since this will likely be a custom deal I know I can get somebody to fabricate a copper one (some have certain elastomeric materials in them). If that doesn't work would it be a bad idea using a regular gasket and a copper gasket (just to gain thickness)? Or what about a copper gasket in a regular gasket sandwich (...as you can tell this isn't my area of expertise!). I really need to make the chamber bigger to accomodate a little more boost, and reduce detonation potential. This with the alcohol injection would probably be a pretty incredible setup!

-The M90 I'll be getting will probably come from a friend of mine who deals with that type of stuff, or from the always convenient eBay. I know, I know watch your ass with this stuff. I'm meticulous and would research the hell out of the car it came off, and talk to the owner. Regardless of where I get it I'll have it properly rebuilt. I believe they offer a couple diffrent pulleys that are indicative of the boost. I'm probably looking at 6, maybe 8 if the injection and chamber expansion go well.

-What is the most effficient system to drive the SC?
1) Off the crack. I guess I could weld a second pulley off it and have it balanced, then run that straight up to the SC. Either extend the fan arm, or replace it with an electric one. Its the most work, but would be great and probably reliable. I could also go back to the original set up easily if necessary.
2)Run the belt off the air pump, to the right side of a fabricated idler pulley, over the SC, the down under (not over like it is now) the existing idler pulley (which i would switch out for a smooth one), then back on track.
3)Weld a second pulley onto the existing air pump and then run a small belt to the SC (probably least efficient and places alot of stress on the air pulley; the stress may be offset however b/c the SC would be pulling from one direction, and the regular belt the other).

-I'm thinking that lightweight pulleys are definately the way to go. Any recommendations here? I figure I'll be loosing some HP already, so getting some back on a pulley would be great.

-The bracket will be plenty strong. I'm thinking of kicking off the air pump as I said before and welding in custom brackets in the area. Any other ideas here?

Anyways thanks again,

James
 

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2004 SL55 AMG
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[8D]
Hi Putter,

I've had my share of fun modifying car and motocycle engines and drive trains to go fast and/or accelerate quicker. before you jump into what will be a huge and costly supercharger project, consider your objectives.

Do you want a higher top speed? Faster off the line? Quicker 60 to 80 MPH time? All three?

Depending on your objectives, there are some less costly and less likely to spin a crank bearing solutions:

1. Shave the head and go gasket-less to increase compression ratio. Be carefull not to remove all clearance between the piston and the valves.

2. Build a ram-air system.

3. Change your rear differential final drive ratio.

4. Improve the aerodynamics, especially underbody.

5. Reduce the weight of the car (wheels, interior, trunk, spare, battery).

Good luck,
Dave
 

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1990 300ce 24v
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Discussion Starter #5
Hey Dave,

I probably should have stated my goals to begin with. Basically I'd really like for the car to have more grunt. I realize that it will grunt when warranted, but I want to be smoother than a hard gear kickdown. If I start in second then I don't want to have to tease the throttle and have an aggressive kick into 1st, but a smooth, yet powerfull jump and go. If I start in 1 I want the back end to be swinging sideways if I want it to. I already know that if you put a little brake check and some accelerator down then you could leave a nice strip. In other words if I have 50 feet to be in the lane beside me at a stop light, then I want a nice 35 foot cushion to the other car! I also want more punch in the middle. So basically I don't need, nor want any super high end. I usually run 80 on the highway and anything over 100 I personally get scared of (b/c cops...not the speed). If I want to go 150 then I jump on my Yamaha. I thought about doing some of the stuff you mentioned but I figured that an SC system won't be that difficult and the rewards will be ridiculous.

I also went back through the records from the previous owner and to my surprise I overlooked where he'd had some head work done. $3,200 worth! Oh and this was 12,000 miles ago! Apparently the heads were blasted and machined, milled flat, all injectors replaced, valve job done, timing chain replaced, new valve guides, new seals, fans, and it was pressure checked. To make it even better a year after thaat the air pump pulley, idler pulley, clutch bearing bracket and radiator were all replaced ($1400). Oil sender and the aux. fans have also been replaced within the past two years (ow past 15,000 miles!) This is GREAT to me b/c I'm sure the leak-down results will be incredible, all the head work has been done, and all I have to do is go in, double check everything and just install a thicker gasket; will drop compression to hopefully 9.0 or lower, and then throw the supercharger on running 6-8 psi, and hitting the 300 mark easily, if not more. I've priced out the braces for the supercharger to be around 250, the supercharger to be around 300 (special deal!), pulleys and belt for about 150, alcohol injection system for about 250, custom piping for about 200 (intake w/large cone filter, and manifold), 50 for a boost gauge, and a few other parts (there are more thats all on the top of my head). So an efficient supercharged system for about 1500. If you like numbers then how about a minimum of 100 hp and at least 120 torque for 1500 bucks (325 hp, 330+ torque).

For now I'll put in that little bit of money when the potential for gain is so huge in all areas. Once I get it done I'll probably change the rear diff or maybe the gear running off the drive shaft. Then I can have a longer 1st, b/c low end and let 4th be a little taller and keep the rpm's down at speed.

***Also does anybody know the stock gasket width for a '90 300ce? I need to send specs to a guy to faricate on for me and I'm looking to increase it by about .05 to .1". Thanks in advance!!
 
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