5.0 merc

[90sunbird]

i have a 98 chapparrla 205le cuddy and it has a 5.0 merc i was wondering if it had a roller cam, and whatkind of a head it has on it,, it is a new style head with centerbolt valve covers. just lookin for some tec. internal specs like valve size, cam size what kind of crank ect..

 

[Bondo]

Re: 5.0 merc

Ayuh,... A 98 Should have a roller cam,+ lifters, along with the Vortec heads...
It no doubt has a cast crank,+ the cam spec's might be found in the manual, or might be a Merc. Secret...
Many of the other Spec's will mirror whatever Chevy were puttin' in pickup trucks that year....

 

[90sunbird]

Re: 5.0 merc

thank you very much the setup runs pretty well for a chev 305 im still tuning it in to my likings,, got one more question why does it run 10* bdc on timing ?? i was thinking fore the hole shot but the motor has plenty of grunt to pull it out of the hole i was thinking about advancing the timing

 

[John_S]

Re: 5.0 merc

thank you very much the setup runs pretty well for a chev 305 im still tuning it in to my likings,, got one more question why does it run 10* bdc on timing ?? i was thinking fore the hole shot but the motor has plenty of grunt to pull it out of the hole i was thinking about advancing the timing

I wouldn't bother messing with it. You won't get much increase, except in the chance of ruining your engine.

If you are going to mess with it and working with a 2brl carb model, make sure it has a knock module/sensor. Some T5 have, some don't. Advancing the initial will also advance the full advance. Detonation will quickly destroy an engine, and is not easily heard in a boat. The knock sensor, if working properly, would help prevent it.

If you would like to mod it (and it is a 2brl), consider a Edelbrock Performer (marinized if neccessary) and a Edelbrock 1409. This will get you 20-25hp. Still not much for a boat, but enough so you would notice a slight increase at wot.