Help picking out a cam...
Skipping ad
|
Given the static floating around about MK cams I'd like to let the OSO brain trust handle this one;)
I plan on swapping out the ZZ502 cam this winter largely because of the 110lsa, idle quality could be better, and I have a Vortech RaceM charger/intercooler that I'd like to use but still have the option of not using it. This boat is largely used for towing tubes and the occasional wakeboarder during the summer, so low end manners are appreciated, with some wide open times in the bay and delta during the fall. It's an all around pleasure cruiser but a little more pep would be nice;). Thoughts? Leave well enough alone? Baja 272 Islander 502 crate motor ~500hp QF850M carb CMI headers (may switch to SM manifolds) 9.6.1 static comp Comp cams steel roller rockers and push rods 1.7 ratio Felpro head gaskets/ARP bolts Forged internals Performer RPM Dual plane manifold Performer RPM oval port heads (fresh rebuild) Cylinder Head Specifications: Combustion chamber volume: 110cc Intake runner volume: 290cc Exhaust runner volume: 110cc Intake valve diameter: 2.19" Exhaust valve diameter: 1.88" Valve stem diameter: 11/32" Valve guides: Manganese bronze Deck thickness: 9/16" Valve spring diameter: 1.55" Valve spring maximum lift: .700" Rocker stud: 7/16" Guideplate: Hardened steel Pushrod diameter: 3/8" Valve angle: 26° Exhaust port location: Stock Spark plug fitment: 14mm x 3/4 reach, gasket seat |
The current ZZ502 cam has.527 intake / .544 exhaust
Camshaft Duration (@.050 in.): 224° intake / 234° exhaust It seems like Crane is having the better choice of cams these days so I'm kicking around these options. It seems like the 791 with its 114 Lsa would be a nice upgrade or the 731 that is the same but with 112lsa. Am I even in the right boat of thinking here? http://i622.photobucket.com/albums/t...099FDABD6A.png |
Actually the 761 looks like a solid choice. I'm trying to keep the existing valve train. I don't know the lifter brand but they are not tied together.
|
You shouldn't have any issues with idle quality and the current cam you have. The 525 efi cam would work really well with that setup and it responds very well to boost. 236/244 @.050 114 lsa. I have one coming out of a motor in the next week. Johnson lifters as well. Cam does have a flat nose for mark iv block...
|
can't help much on cam, but I ran a HP500 with a procharger for years, several carbs and EFI, last setup had to go down to a 750 from a 850 to keep from leaning out at WOT, thanks god for widebands. the air was being blown thru so quickly that would not pull fuel, the 750 worked perfectly
|
Originally Posted by Baja Rooster
(Post 4489809)
Actually the 761 looks like a solid choice. I'm trying to keep the existing valve train. I don't know the lifter brand but they are not tied together.
|
I like the 525 EFI cam or similar
Since you tow tubers and wake boarders, I'd look into selling the centrifugal, and picking up a 250 blower. Couple that to those oval ports , should make more than enough low end, and good top end as well. Throttle actuation and response down low with a roots is very good. |
I'm just thinking of his poor drive.700+hp is not gonna be kind.:D
|
Originally Posted by sutphen 30
(Post 4489846)
I'm just thinking of his poor drive.700+hp is not gonna be kind.:D
|
All times are GMT -5. The time now is 03:43 PM. |
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.