Is a 302 EFI cam the same as a reg marine cam?

[nitrocharger]

I am replacing my '94 VP 302 EFI motor with a rebuilt one that already has a marine cam installed. VP wants $260 for the cam that is supposed to go with that motor but my question is how different are the two cams? I'm worried that the EFI is tuned to the "special" cam and if I use anything else, the engine wont run right. what do you guys think?

 

[jimmbo]

Re: Is a 302 EFI cam the same as a reg marine cam?

Unless you can get the installed 'marine cam' measured how can you compare it to a VP speced cam? Even if the duration, overlap and lift are the same you can't be sure the lift rate is the same. I guess it comes down to how much faith/trust you have in who rebuilt the engine. The EFI will have some sensors that will give the computer info on how the engine is running but it is based on a cam of a certain grind. Auto engines read the exhaust with O2 sensors, Marine engines up till very recently did not have these. It might be able to adjust mixture and timing to some degree, but it might not and you could end up with poorer performance.

 

[Boomyal]

Re: Is a 302 EFI cam the same as a reg marine cam?

Cams can play a signifigant role in the operation of EFI systems, especially when the EFI systems rely on vacuum signals for their operation. There is usually an envelope of cam specs that will work within the particular requirements of any given EFI system.

Not exactly sure how you would determine all of that but at least for higher volume automotive EFI systems, the cam manufacturers know what will work and what will not.

I'm not entirely clear on my definitions here but some EFI's are mass density and some are speed density. I other words, some EFI's run off of vacuum signals and some work off of airflow thru the intake. The latter are much more flexible on changing all kinds of factors like cams, compression, etc, etc.

 

[Tail_Gunner]

Re: Is a 302 EFI cam the same as a reg marine cam?

I am replacing my '94 VP 302 EFI motor with a rebuilt one that already has a marine cam installed. VP wants $260 for the cam that is supposed to go with that motor but my question is how different are the two cams? I'm worried that the EFI is tuned to the "special" cam and if I use anything else, the engine wont run right. what do you guys think?

Probably right, timing issue's I