Vortec Roller Upgrade

[21eagle]

I run a 1989 baja with a 1989 350 mag at 53mph. I am looking to buy a new 350 Vortec roller motor they say is 325hp. Do you think this will get me over 60mph. I am also adding GLM high performance manifolds and risers. Let me know if not try somthing else lol anyway to squeeze a few more out of the new vortec Chris

 

[Shaun78]

Re: Vortec Roller Upgrade

http://www.perfprotech.com/store/catalog/GM-Big-Block-74L454-cu-in-1984-2001,2888.aspx

get the manifolds/risers from this company.(small block version) They are ceramic/EDP coated and will last longer. I don't see what makes the GLM's high performance.

 

[John_S]

Re: Vortec Roller Upgrade

"Do you think this will get me over 60mph"

Probably not over, but closer. The 325hp rating is probably at the crank, vs prop. So, probably 300hp at prop. If carbed, they would probably be running a stouter cam that stock Merc roller. Exhaust upgrade, maybe another 5%. So at the prop, you are talking about 50-65HP increase over current mag. A very rough rule of thumb of 10hp per mph, gets you close, but will depend on your hull. Also the rough rule doesn't stay linear! especially as you hit higher speeds.

PS: Another factor to consider is that most crate engines are dynoed with headers or dual open exhaust. This inflates the hp rating when put in a boat. For a stock like engine, probably only by 10%.

PSS: Building a 383 SB "should" be able to push over that threashold. You would probably want to visit some of the "go fast" boat forums, to confirm others with your hull acheived that milestone.

 

[wire2]

Re: Vortec Roller Upgrade

Get your hands on a higher pitch prop too.

My 19' Glastron 5.7 came with a 21. After some engine upgrades, wot is 58 mph @ 5500 rpm. I will have a 23 on it for next season.

 

[Mkos1980]

Re: Vortec Roller Upgrade

(Chaparral 2150 SX 21P Laser II ) I'm currently going same route as you. My boat cam with the stock 5.7 260 HP and did 52.1. I added a bowtie high rise intake (only differance between stock and the MAG version) and go to 54.6. I'm keeping the stock heads for now, but just got a Crane compucam 2032 cam for it and upgarded roller valve train. I'm also going with the GLM's or the Revolutions. With the HP differance and the weight savings of the aluminum. I hope to be high 50's. Why not keep your current motor and do a head cam swap? The shortblock is the same.