Engine swap or?

[nostat]

I have a 74 450sel US model. With engine parts becoming more expensive or even NLA I'am looking for alternatives. Currently my pulse points are bad and a new set is a $1000.00, repair kit $500.00 and used (went down that road already only lasted 2yrs)and I'am looking for alternatives. Does the Mega Squirt system solve this problem or is there another system that will fix my injection problems. Or what would be an easy engine swap? I'am not looking to build a race car but I also don't want to make a lot of chassis mods to change. I know some people have gone with the LS engine but has anyone used a older model american small block V8? They are easy to mod for more HP, parts available and I'am old and very familer with older GM and Ford. Thanks.

[BWhitmore]

Small block Chevy V8 into a W123 car is a common and not too complicated swap. I would think similiar issues with your car.

[97 SL320]

Pulse points as in the set at the bottom of the distributor on D jet FI or the points under the distributor cap that typically trigger the ignition coil or ignition box on some MB?

If D jet points, I'd be tempted to make a shutter wheel and use through beam optical sensors + some circuitry. Omron and others make a u shaped transmitter / receiver that is sub 1" x 0.75" x 0.325" https://www.ia.omron.com/products/category/sensors/photomicro-sensors/slot-type/index.html
.
If the under cap points, some install a Pertronix electronic ignition kit.

A 90's GM DIS brick ignition system could be made to work, the GM 4.5 ish Cadillac V8 used these as did many 4 and 6 engines. ( 2 of the 4 cyl packs could be used )

You would need a crank trigger and some method of developing an advance curve. Someone is bound to have done this before.

If you are going to make an engine swap, a GM 4.3 V6 , 5.0 - 5.7 V8 throttle body injected from a 90's pickup / fill sized car would be easy project from the electrical side of things. ( assuming the engine fits under the hood )

[vandor]

The easiest engine swap would be a 5.6 liter m117 from a 80s MB. Just use it's stock fuel and ignition systems.
Megasquirt would be a good option for the current engine, it would have more power and better economy. BUT hopefully you would be able to find someone who already has the files for the 4.5 liter m117, because programming it from scratch is a lot of work.

[Mike D]

Programming the MS is a piece of cake. If you don't feel like fine tuning it manually then use the TunerStudios software.

[t walgamuth]

I agree if an engine swap is desired a good candidate would be the 500E motor from an 84 mercedes. The engine is robust and simple to run and maintain. The injection is completely mechanical so computer problems are not a factor.

I had an 84 500SEC which I ran about 50,000 miles in three years. I found the 500 motor to be comparable to the 300D on maintenance but it did use a lot more fuel, never really breaking 20 mpg at any speed. But it also would not break a sweat running 85 on the highway if you didn't mind paying for fuel at 13 mpg.

[Idle]

On engine swaps in general....

Back in the 80's people were not able to wrap their heads around a lot of the newfangled electronics. So engine swaps were a common thing. Tear out the old engine and stick in a used one from the late 60's, early 70's.

And the real pros at this always looked for truck engines. The difference was truck engines were said to have stronger crankshafts. Since the cost was the same at the junkyards it just made sense to go with the better crankshaft.

But that was then and this is now. Anyone know if this still holds true with engines from the 90's?

[fonzi]

Originally Posted by nostat

Currently my pulse points are bad and a new set is a $1000.00, repair kit $500.00 and used (went down that road already only lasted 2yrs)and I'am looking for alternatives. Does the Mega Squirt system solve this problem or is there another system that will fix my injection problems. ..... I also don't want to make a lot of chassis mods to change.

MegaSquirt would certainly eliminate the entire fuel management system, everything d-jet. And of course you can eliminate the transistorized ignition and the ignition points with the inexpensive pertronix solution. Then you just have to make sure you've got a good block and good heads and you don't have a totally modified car.

But the iron low compression v8 is relatively low on the power-to-weight ratio. That's the only reason I'd consider going with something else. But plan on cutting or replacing your springs and getting different handling behavior when you start down that road. I always enjoy reading the threads though.

I want to put something like and m119 into a w108. Maybe the m104 I recently got would be nice, but nowhere near the m119 power.

Does anyone know the weights of various engines? Like: how does am m119 compare to a 72-75 4.5?

[TZ_280SEL]

I am a Mega Squirt guy. I recently (6 mos ago) converted my 72 280SEL4.5 to Mega Squirt. I did the entire thing. I'm running wasted spark with individual coil packs (I chose to use LS2 coils), a 36-1 wheel on the crank, semi- sequential injection utilizing 19# Bosch injectors, DIY fuel rails from Ross, and a few other tid bits. I used a new throttle position sensor on the existing throttle body and have adapted a auxiliary air valve from an 80's jeep 4.0 liter so I could control cold start and warm up idle.

I did all of this because I was tired of dealing with old components that never seemed to work the same way one day to the next. My car ran fine cold (although, very rich), idled poorly when hot, missed badly when humid or raining etc.. The distributor and other misc D-Jet equipment was original to the car and so it had about 500,000 miles on it.

It cost me $1243.03 to do the full conversion including all the wiring. I used all new automotive connectors and did a cold air intake as well.

I can tell you, it is like driving a totally different car. I have also noticed that my oil used to turn very black in the first 500 or so miles after a change. I changed oil about 1500 miles ago (after the conversion) and the oil looks like new and has not moved off the full mark so I think I used to be dumping a lot of fuel into the cylinders.

[TZ_280SEL]

here is my engine bay now

[Idle]

Originally Posted by TZ_280SEL

I am a Mega Squirt guy. I recently (6 mos ago) converted my 72 280SEL4.5 to Mega Squirt. I did the entire thing. I'm running wasted spark with individual coil packs (I chose to use LS2 coils), a 36-1 wheel on the crank, semi- sequential injection utilizing 19# Bosch injectors, DIY fuel rails from Ross, and a few other tid bits. I used a new throttle position sensor on the existing throttle body and have adapted a auxiliary air valve from an 80's jeep 4.0 liter so I could control cold start and warm up idle.

I did all of this because I was tired of dealing with old components that never seemed to work the same way one day to the next. My car ran fine cold (although, very rich), idled poorly when hot, missed badly when humid or raining etc.. The distributor and other misc D-Jet equipment was original to the car and so it had about 500,000 miles on it.

It cost me $1243.03 to do the full conversion including all the wiring. I used all new automotive connectors and did a cold air intake as well.

I can tell you, it is like driving a totally different car. I have also noticed that my oil used to turn very black in the first 500 or so miles after a change. I changed oil about 1500 miles ago (after the conversion) and the oil looks like new and has not moved off the full mark so I think I used to be dumping a lot of fuel into the cylinders.

Thanks for posting this real world info. I have been toying with a 4.5 for about two years but every problem you mentioned above has kept me from it.

I once had a 230 with the Stromberg sidedraft. When it was set up right it ran like a swiss watch. But it didn't take much to knock it off center.

I guess I am getting to old to want to mess with the constant adjustments that were necessary during the early 70's.

[nostat]

Thanks for the info I'am in contact with a tech from mega squirt to find the right set up for my car. With your help looks like no engine swap for me.

[oldsinner111]

I would order from jegs, a throttle body injection,and electronic ignition.