Question on Z porting VS. Bridge porting?

[Riverracer280SS]

I need to know which design produced more power, and which one had the bigger ports. ,Thanks Scott

[us1]

My Z port has a wider exhaust port and should put out more power than a 2.5 Bridgeport.Keep in mind the Bridgeport was never came in a 2.5, the Z Port is a 2.5. I have made three 2.5 Bridgeport’s and the problem with them is they are a little down on low end torque compared to the oval port 2.5. But the top end is still there. I have not run my Z Port on the dyno yet, but I can post the results. On the boat tests it seemed to run great, lots of power.

[Sam Baker]

Typically, Z-port motors put out more peak horsepower, but every high horsepower Z-Port motor I've seen doesn't live up to a good standard port motor. The power curve seems to be less consistent. Case in point was this past weekend at the Ottawa race. A guy was there with a "bad-ass" Z-port motor on an Allison, but Jeff Cleinmark bitch slapped him with his standard 2.5 drag port motor.

There may be guys getting them to run, but from what I've seen in the real world, they are kind of like the 450 HP 2.6 and 2.7 liter motors you hear about but never see win races.

Sam

[fasterthanyou]

I know some of those guys who drag race and my opinion is that they are loosing transfer volume when they put a bigger piston and sleeve in a 2.5 block as well as the issue of more rotating mass it seems like a good idea but mercury usually hits the target when they design something. Engineers like Gene Trickel who has since left mercury and does his own work (a very busy guy)but he is one of the good minds that came out of mercury a little conservative but as sharp as they get!

[Firestarter]

2.7 Motors work (for a short time)on the offshore stuff. I have seen a 32 Skater with triple 2.7's on pump fuel run 130mph. That is 15mph faster than the "stock" record in offshore. Not everyone drag races, their are other uses for these motors.

RT

[Jay Smith]

I had a Z port motor with the block done by the most talked and bragged upon Z port builder (out of country) around and the sleeves leaked water so bad the thing scuffed pistons on the water hose. No thanks I'll stick with the Drag motor never seen a Z stick with them for the long haul and believe me i've looked at a few in ten years. Like in earlier posts you can open up the exhaust port thats true but something has to be said about the post in the port exit the diaginal or by that matter in the center
( bridgeport ) got to be disruptive to the out going exhaust charge and negate all that was suppositive picked up by the widening of the port, hell ibridgeport motors were a bad design or they ( mercury ) would be still making it. Another problem is how to cool the sliver of medal in the sleeve at the exhaust , you can only disapate heat with metal volumn and denisity not just a small diaginal or vertical sliver.

My thoughts and experience,
Jay @ JSRE