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Discussion Starter #1
If you were going to use OEM MAF EFI on a 289/302 with a flat tappet cam what would be a good choice. This would be a daily driver and I am looking for good fuel mileage and 5.0 HO type performance. Any suggestions appreciated.
 

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First is to know the rest of the engine build, as it all plays a part in cam selection. So, tell us everything about it.

Second is to know everything about the car and how it is to be used. Weight, gearing, converter stall, etc., plus street, combo, road race, auto-cross, etc.

Last, be aware you must use a cam with the same firing order as an HO if using an HO computer for best results. The easy option here is to use a 351W cam. It must also have relatively short duration and wide lobe centers to work well with the MAF EFI, especially if you don't plan extensive re-tuning. Give us all your info and we can zero-in.

David
 

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Try comp cam cam selection tool.
 

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Discussion Starter #4
It would be a pretty much stock rebuild for a car I will literally drive daily to work. The engine would use .030 over flat top pistons with stock 66 289 heads with the adjustable valvetrain. It would probably have 9.0 - 9.5:1 compression. It would go into my 86 T-Bird with a C4 trans, stock converter/stall and stock 2.75 gearing in the rear. I want something that is compatible with the HO calibration in the MAF ECM. I do not want to have to worry about re-tuning the ECM. I would probably use a set of aftermarket shorty headers with dual exhaust.
 

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That would be a roller cam from a 5.0 HO. I am looking for a flat tappet HO ECM compatible alternative.
get All the oem spec for the roller . then try to match the SAE to .200" lift duration to a flat tappet

most cam companys have a listing of lobe profiles
 

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Good. With that weight and gearing, you won't want to stray far from the stock cam spec's range. So, you are looking for a standard hydraulic flat tappet cam for your non-roller block, using the 5.0 HO/351W firing order. It needs roughly 205° (HO) to 210° (Cobra) duration at .050", and lobe separation angle of 115° (HO) to 118° (Cobra) as the two primary factors to have it run well with HO MAF SEFI. Reality is that you can stretch duration up to perhaps 220° and shorten your LSA to 114, and possibly a bit less, without re-tuning. There are a bunch of cams with 112° LSA, but a light re-tune will likely be necessary.

So there ya go. Find one in those parameters with as much lift as you can get and you should be able to plug 'n play with your ECM as well as get reasonable performance from the remaining engine and car spec's. Be sure you match your valve springs to the cam.

David
 

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Discussion Starter #9
Thanks for the input everyone. I have actually considered using an early factory 351W cam. I will look into what is available in the those parameters PSIG and decide what I want to do.
 

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... I have actually considered using an early factory 351W cam. ...
Indeed, the 351W HO cam (E0AZ-6250-A) has spec's falling right into the soft side of that bucket (.444/.452-206/221-115 LSA), with a bit of extra exhaust duration for your smaller exhaust ports and valves to boot. Throw some 1.7 roller rockers on there for a kick in lift and drive happy. Interesting to note the old 289 K-code cam is very close to an identical match to the Cobra roller cam - just the wrong firing order. I'm not saying to go with anything particular, but it's a cheap option. I might order a cam from the lobe catalog, or have a stock one re-shaped and ground to my spec at Delta Cams, for example.

David
 
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