More CFM (Bigger Intake) 502/415 Merc.
#1
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I am looking for an aftermarket intake for a MerCruiser 502/415 EFI motor. The curent EFI and intake are stock MerCruiser. I have a new Dart 540 cu.in. with 320 heads, and I need more air. Who manufactures an 850 cfm to 1150 cfm intake for this application with the same (roughly) external physical dimensions as the MerCruiser intake I have now? What is the cost? Any info. would be appreciated, this is in the tire kicker stages now/gathering info., and I am not ready to pull the trigger yet, but would like to know my options and what experience the members of OSO have had in a similiar situation.
Thanks
Stephen
Thanks
Stephen
#2
21 and 42 footers
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A buddy built a 540 from his 502 mag....ended up going to carb's for airflow reasons. I have 500efi's that are now 540's. Even that intake/plenum with the monoblade TB on my motors is restricting airflow. If you stick with an EFI setup send the motor to Precision Marine.....he's got mine dialed in and running good!!!
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![Default](/forums/images/icons/icon1.gif)
I am looking for an aftermarket intake for a MerCruiser 502/415 EFI motor. The curent EFI and intake are stock MerCruiser. I have a new Dart 540 cu.in. with 320 heads, and I need more air. Who manufactures an 850 cfm to 1150 cfm intake for this application with the same (roughly) external physical dimensions as the MerCruiser intake I have now? What is the cost? Any info. would be appreciated, this is in the tire kicker stages now/gathering info., and I am not ready to pull the trigger yet, but would like to know my options and what experience the members of OSO have had in a similiar situation.
Thanks
Stephen
Thanks
Stephen
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#7
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I will go with none of the above suggestions (for now) but thank you all for your input. EFI, mild cam (to avoid reversion), liveability, and more hp is what the goal was with these 540's, and not to abuse the drives too much. The motors were just put together an Innovation, and I am not impessed with the final hp(but that is not Innovation Marine's fault); my father ordered these motors and cams (short blocks before he passed away) -- 540's with a mild compression (doesn't help make hp, but is cost effective for fuel) and a mild cam with Gil exhaust and silent choice restrict how big a cam that can be utilized to gain more hp.
I am really suprised that there is not an aftermarket plenum with bigger cfm available for this application. I am not against throwing a Dart intake and an 1150 Dominator on top, but for now it will stay an EFI boat.
I am really suprised that there is not an aftermarket plenum with bigger cfm available for this application. I am not against throwing a Dart intake and an 1150 Dominator on top, but for now it will stay an EFI boat.
#8
21 and 42 footers
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HaHa..."none" ![Smilie](/forums/images/smilies/smile.gif)
I don't blame you.....My 540's aren't getting enough air according to the shop that did the tuning but I wanted EFI as well. Made 630hp (5,200) and 700tq (4,300) but have been told I probably left 35hp on the table by not using carb/intakes. I did up my compression to 9.75 with a decent cam.....love the way it sounds!!!!
![Smilie](/forums/images/smilies/smile.gif)
I don't blame you.....My 540's aren't getting enough air according to the shop that did the tuning but I wanted EFI as well. Made 630hp (5,200) and 700tq (4,300) but have been told I probably left 35hp on the table by not using carb/intakes. I did up my compression to 9.75 with a decent cam.....love the way it sounds!!!!
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To stay with fuel injection, you can go with the Edelbrock Victor Jr EFI intake and throttle body setup. The intake is a Victor Jr machined to accept fuel injectors, rails, and sensors. The throttle body mounts just like a carb would. No reason you couldn't keep the merc computers, but it would need to be tuned to run with the new intake (any new intake for that matter).
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