4 BBL Carb Performance Gains.

[Senior B]

Am tinkering with the idea of swaping my Holly 2300 2bbl Carb for a Holly 4160 4BBL Carb. I'm curious of how much performace on the top end I can expect to get. I have a 2002 Glastron 205 GX powered by A Volvo 5.0 GL-B and pushed by a SX drive with the 1.60 ratio. I run a 19 pitch prop to ski and a 21 to cruise. I can get 4600 rpm at wot on the 21 and 4800 with the 19 . My top speed is @ 52 on the speedo with a full tank and 4 folks in the boat. Thanx.

 

[Boomyal]

Re: 4 BBL Carb Performance Gains.

It might scare you to death, or at least drain your wallet if you do not use the extra power judiciously. If you can stay out of the secondaries you will still have good economy but the temptation is to play (then Pay)

My experience include switching to an Edelbrock Performer manifold, something you do not want to do if you are raw water cooled and running in salt. You'd still get a big bang even if you had to use an OEM iron manifold.

I'm just about ready to switch another ford 5.0 to 4 bbl. This time I will use the OEM iron manifold and a rather more expensive Holley 4160 450 cfm 4 bbl. This new boat is basically a 50 mph hull and I am expecting some signifigant gain in both acceleration and top speed but without the same fuel penalty as my other 5 liter. That one is so quick it scares me to open it up.

If you do use a 600 cfm 4160, you want to make sure it is jetted for the 5.0. 600 cfm is pushing the limit for a stockish 5 liter. Many 4160's are jetted for the 5.7. You do not want that.

 

[jimmbo]

Re: 4 BBL Carb Performance Gains.

The 500 cfm holley that comes on the 5 litre VP is sized perfectly for that engine. Flow rated like a 4bbl it flows 370cfm

305 cu in divided by 2, times 5000 rpm, divided by 1728 cu equals 441 cubic ft per minute at 100% volumetric efficiency. At 80% VE, 353 cfm

It is unlikely you will see any gain

I did the swap but my boat, a 2002 Glastron SX 195 has a 5.7 in it. There the 2 bbl is a bit too small. I gained about 275 rpm going to a Holley 650 spreadbore. Manifold did not need swapping cause VP uses a very good 4bbl manifold on its engine and uses an adapter to mount the 2bbl

 

[Bondo]

Re: 4 BBL Carb Performance Gains.

About 20hp.......

 

[whywhyzed]

Re: 4 BBL Carb Performance Gains.

My top speed is @ 52 on the speedo with a full tank and 4 folks in the boat. Thanx.

The extra 20 HP will give you another 1 mph, maybe 2.