Hey guys, I am restoring a 1987 272 SR1 for a family friend. It has 350 magnum small blocks and counter rotating Alpha drives. I already re-built the Alpha transom plates and freshened up the drives. My question is, how will the boat perform with the stock 350's? I am looking to purchase two new or re-man long blocks. I am trying to decide if it is worth the extra cash to upgrade to the Vortec 320 horse long blocks. We are on a budget with this build, and the Vortecs are a bit more $, because we will need new intake manifolds and electric fuel pump kits. However, the extra power would be nice!!!

Does anyone have experience with an upgrade like this? If it's only going to be a few mph faster, I don't think he will go for it. Any advice is appreciated! Thanks.

I would do the upgrade! Even with the 320's you'll only be in the low to mid 60's.

Randy,

Check out my thread http://www.offshoreonly.com/forums/f...or-update.html

...and now you understand why I went to the Vortec. The Vortec heads are the biggest improvement to the Small Block Chevy since "186" and "041" Double Hump heads were in the '60's. There is an immediate 40~50 horse pick up just with the heads. Match that to roller cam technology and it's easy to get a 400 ft lb+ torque engine and reliable 375~400 horsepower. You are approaching stock Big Block numbers with out the weight.

The Bravo drive upgrade is a personal decision I made because of the type of long range trips I like to take. In the open ocean far from shore I want the reliability.

Arguments can be made that the older style hulls will never get past 75 MPH with Small Block Power unless you start adding blowers etc. I'm not about top speed as an ultimate goal but more about being able to maintain a long range 55~60 MPH cruise for hours at a time. Vortec engines and Bravo drives will reliably achieve that goal.

I vote for the Vortec upgrade...go for it.

Thanks for the advice guys, I did some searching on this site, and guys say that the 272 will do low 60's with stock 260 horse 350's, but I find that hard to believe. What do these really do with stock motors?

My 272 i had with 648 hrs the only thing was K&N flame arrestors and MSD coils. 59.99999 @ 5000 spinning 23 standard mirage props. that boat gave me 3 seasons of fun boating. it is hard to beat the SBC alpha pkg in a 272 for cost and reliability.

I am redoing my 86 - 272 and also went with Vortec heads. Mine was a bit easier since it will only see fresh water, so I picked up used automotive heads and will pick up two aluminum aftermarket intakes by professional products or edelbrock. Being in NY, you are probably going to be looking at salt water. If so, check the cost of the marine rated intakes, might get a bit "salty".

Brian

Thanks for the advice guys, I talked my buddy into ordering 2 new Vortec long blocks today. It will be more money, but I think it will be worth it. Really want this thing to move. I like the idea of roller cams, and the Vortec head design is great. Plus, the motors are new, not remanufactured, thats awesome!

My previous boat was a 1988 272 with 1994 350 mags rated@ 250prop HP ran 59-60 on gps..I went to 350 mag mpis with counter rotating drives. The new engines were rated at 300 prop HP. It only gained one mph but quicker acceleration. The props were 23 mirage. The performance gains weren't good so don't do what I did if you want to see faster top end.

You gained 1 mph with a 100 hp increase?

We had a 87 272 with 350 mag 54 on gps . Installed Bravo 1 drives and 383's 425 hp and got 69 on gps with 23 pitch props !!!