powerquest208

I just upgraded from an Viate 208 XL to the 270. My 270 only has an 310hp 454 mpi. Most of my experience is with carb motors. Cant make adjustments to mpi. Need to pump it up. What do I start with & what mods worked best? Ive only been in it 3 times so i don't have alot of experience with the 270. First thought is to move it up to a 23 pitch Mirage. It has 22 pitch 4 blade & it maxes out the rpms. Got a steal on it but is slower than expected. HELP?
Thanks.

Knot 4 Me

What are your performance goals and budget? The 7.4MPI is not a good platform to build from. Any serious increases in speed will have to be obtained from a different powerplant.

johnny b good

Your most economical and best bang for the buck would probably be getting the right prop and have it blue printed.

speed demon

I would think dropping in a good used 502 Mag or 496 Mag HO might be the most cost effective upgrade and very reliable. I have a 95 Laser with a 454Mag 385 hp and it does 55-56 mph gps 3/4 tank gas in calm water trimmed almost all the way before trailer tilt. The best I have seen is 58.5 mph gps 1/4 tank gas. My friend has a 93 Laser with a 502 and says he sees 62-63 mph gps regularly.

A labbed prop would be good for 2-3 mph. There is a guy on this board with a 270 that put on a 2 inch shorter lower unit and saw 5-7 mph gain. His 454 Mag motor is built up to 550hp as well I believe.

270's are nice boats but not the fastest.

If I have the coin a 300 Revenge with 496 Mag HO's does 80-82 would be a great Lake Michigan boat. Someday?

pkspx

I can talk all day about this boat, I posted in your other thread. My 270 is spectacular with the engine mods. Dean Gellner from Gellner Engineering did my work, contact him and he will give you all my specification on my engine. He can extract more ponies out of yours very easily since he knows my boat. He has been out for a ride with me, coming from a guy that has been on outerlimits, he's very happy with the results. The guys great!

216-398-8500

powerquest208

PKSPX! I read your other post! Basically you started with the same package. What was the cause of the first build burning #7 cylinder? How does this boat handle @ 69mph? What is the determining factor for needing hydraulic steering setup? I have been watching for an 502 or 496HO drop in for sale. Thats what most people recommend. But that will only put the motor in the 400-425 range. I don't have a problem building a motor but i like to have an good idea of the outcome before I start. I have seen people just pour money hand over fist without significant results. I found a Procharger very cheap but kind of afraid that the motor will not hold up! Budget around $3-5k for now! Speed? Do you ever have enough?

pkspx

not sure what happened to that cyl 7, it was a freak accident. I was told that 454's did have problems with weak blocks though that generation. The boat needs more hull. I can use a lot of tab to control it for a smooth 65mph run but it still likes to get loose. My tabs are normally set at 8 believe it or not. You DEFINITIVELY need hydraulic steering. You could feel the boat loose in the steering right away. You can build yours or supercharger but remember if you build your engine correctly at least it will be sound, your gonna need a rebuild at some point with that blower engine. Check your PM I sent you my mobile number we can talk further about it.

laszlo01

Put a blower on it and you are good to go.