CDM Motors

[Glastron1987]

Besides making the engines more difficult to modify and get more RPMs, are the late 90's 200 CDM engines good? Is the rpm limit 5800?

[tlwjkw]

tha motors are as good as any production motor but makin' it a hot rod jus not gonna happen with those 'lectronics.... 2.5 cdm, 'lectronic motors didn't show up till 2000................... jmo.

[25two.stroke]

The CDM motors were badass in my opinion. Rock solid ignition system compared to stator, trigger, switchbox and coils. HOWEVER: when the CDM ignition goes haywire you have to either have the merc troubleshooting manual or a 100% understanding of the electrical flow through every component or else you will enver find out which part has failed. Every component is dependent on another, unlike the earlier ignition systems.

Not all of them had a rev-limit and it is possible to build a cdm ignition engine unlimited.

[tlwjkw]

Not all of them had a rev-limit and it is possible to build a cdm ignition engine unlimited.

not a doubter but this, ona 2.5, ya gotta show me how!

[25two.stroke]

I'm working on one right now...tryna get a lightweight wheel to work on it right now. If it all works out I'll make a thread on it.

[tlwjkw]

would like ta know.. i jus think if it was $ worthy it would have already shown up on some of tha hot rods out there over tha years................

[FORBESAUTO]

They are very reliable units. If ya could figure out how to “tune” em and take out/ adjust the timing delay and rev limiter, I think they would be a great performance piece.I had CDI try and tweak mine with no luck. Never got it to perform no where near like my switch box set up, and rev limiter went lower instead of higher ! If ya figure out how take control of em, please let us/me know.

[OnPad]

I have a 2000 efi cdm engine, that I bought super cheap last year. As I've researched the system I now own, it appears the first gen cdm (non motorola?) Efi version is rpm limited by fuel in ecu. The same as a switchbox Efi.
The carb version is said to be limited by the control module, which is the doohickey that takes the place of the switchboxs. Really not that much different than a switchbox engine.

Not a ton of info about hopping up this cdm system exists. Anyone that has good info should chime in.

[tlwjkw]

tha cdm stuff has been on tha 2.5 for over 23 years.. so there's that... only first two years with an ECU then went to tha module controlled.... not a person alive on this site or any other hot rod outboard site could keep a secret like that that long..............................

[OnPad]

Has anyone run a brucato on a cdm efi engine?
Or anyone try a efi control module on a carb engine?

I just read the other day that someone was spinning the stock efi version at 63 or 6400 rpm.

Maybe I'll slap mine on my bullet this summer and see if the ignition system is going to cut the mustard. If not, I bought the wiring harness to convert it over to sb ignition.

[25two.stroke]

Has anyone run a brucato on a cdm efi engine?

This is what I have in the works.

[tlwjkw]

This is what I have in the works.

laser or downdraft?

[25two.stroke]

crankcase

[tlwjkw]

so are you using a 260/280 style crankcase injection with 280 (cdms) 'lectrics?

[25two.stroke]

so are you using a 260/280 style crankcase injection with 280 (cdms) 'lectrics?

Not really