Squeezing more power?

[alilegend]

Hello people I own a 1975 mercedes w115 230.4, I know it's not built to be a power house but is there any cheap and cheerful performance mods I can do to help the engine run better and/or even squeeze abit more power out?

Thanks

 

[John Jones Jr]

Cheap: Custom Exhaust system, retro fit aftermarket Electronic Ignition system, Electric fan maybe?. You might be lucky to see possibly 10+bhp with that lot? Better throttle response and a modest improvement in MPG as a bonus. Change the tyres to an 'Eco' type giving less rolling resistance, lighter 2nd hand alloy wheels. Keep the car clean & well polished. Fit a lower ratio diff, better acceleration at the expense of MPG. I'm sure there's a few other items too.

Almost everything else is more expensive including the obvious route, carry out an engine transplant, a 2.8 for example.

 

[grober]

Some people stick a progressive choke Weber on them. This is normally to improve driveability and fuel consumption rather than gain power but your carburettor may be quite worn anyway. http://www.jameng.com/products/Mercedes-4cyl-32{47}36-DGAV.html
DGV Carbs
The 32/36 DGV Series carbs were designed to provide an economical performance carburetor that increases power, improves driveability, and offers better fuel economy over the stock OEM carburetors. The DGV progressive carburetors are pre-calibrated from the factory, and set to run on stock engines. If the engine has been upgraded or improved with other performance items, such as a camshaft or increase compression, they may need to be re-calibrated or re-jetted for some applications. The 32/36 DGV is a progressive carb, so only the primary barrel is used for low speed operation. The secondary barrel only opens when additional air flow is required, for wide open throttle or high speed operation. As a progressive style carburetor, it offers excellent throttle response and fuel economy, as well as high end power when it's needed. The DGV's are an excellent 2V carburetor to use on stock and/or mild performance engines, and they are a great replacement carb for worn out or hard to maintain factory one barrel carbs. If your concerned more with mileage, low end power, and do a lot of city driving, this is the carb for you.

DFV Carbs
http://www.classicinlines.com/Weber3236.asp

 

[John Jones Jr]

Personally, I wouldn't go down the twin choke Weber route as I don't think there really will be gains in MPG nor do I think it's potential performance/cost benefit can be maximised without doing a head job (possibly with a suitably higher lift cam) and decent flowing exhaust manifold - after all performance is the goal. Of course I stand to be corrected on that view.

Bear in mind too, it will cost the guts of a grand by the time the carb is fitted, tuned and sundries. Two grand gets a modern EFI including ignition.

I would overhaul the current standard carb though and have it set up by a garage.

 

[John Jones Jr]

One other point. Before spending money to up performance, make sure your engine is in rude health first, otherwise you're wasting your hard earned.

 

[grober]

This is a detailed write up on tuning these carbs.
Weber 32/36 Setup, Ch.1 | SV3Power Products

 

[grober]

Webcon UK Ltd - Welcome to Webcon UK Ltd

specifically
Webcon UK Ltd - Universal Kits

 

[grober]

OR there's always mega squirt! M115 T.B.I. conversion - PeachParts Mercedes ShopForum

 

[alilegend]

thanks for the replies lads, apparently the carb was cleaned and re set just before I purchased the car, I'm not really wanting to go down changing the carbs etc, just subtle things like if there's a direct replacement better exhaust/intake manifold? Or air filters? Thanks

 

[BlackC55]

I would put a modern V8 in. A 113 engine is peanuts.

 

[John Jones Jr]

thanks for the replies lads, apparently the carb was cleaned and re set just before I purchased the car, I'm not really wanting to go down changing the carbs etc, just subtle things like if there's a direct replacement better exhaust/intake manifold? Or air filters? Thanks

Inlet manifold & air filter change I doubt will give you any gain. So, if it's just subtle changes I'd go:

1. Tune up on a Rolling Road, making sure the engine is good along with getting actual BHP & Torque figures.

2. Fit modern retro Electronic Ignition.

3. Fit a freer flowing exhaust.

4. Electric fan with adjustable settings.

5. Fit an engine undertray, if not fitted currently. 6. Low rolling resistance ECO tyres along with 7.lighter wheels. 8. 20-30mm lowering springs. 9. Smaller more modern alternator. 10. Smaller lighter battery if possible. 11. And keep as much 'junk' out of the car when practical. 12. See, if the cold air feed an be improved to the air filter housing.

It all adds up. If you managed just 1% gain on average just for the sake of this exercise from each item above: power, less weight & better aero, you're looking at a total gain of 12% (I'd hope to see that from just items 1, 2 & 3). All in all, there should be improved power, MPG, driveability and handling.

 

[Moorej]

Hello
Has anyone had the experience of swapping the solex 4a1 from a 250 w123 with the m123.921 engine with a Weber o another brand of modern carburetor

 

[E55BOF]

Welcome to the forum. It might be better to start a new thread for your query, though, rather than reviving a five-year-old thread related to a different car altogether.