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Anyone running delta cam/shaved heads/spfi

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bunch on EA81's and I don't see how SPFI impacts the cams, delta makes cams for SPFI EA82 and MPFI EA82, ER27, EJ....sounds pretty basic. 


I'd guess some of these guys have SPFI but I didn't investigate:



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Only reason I asked was I had been sort of advised that it wouldn't work by one of the gurus, looking for people who've applied it, or tried to. Seeing if I wasted money getting a delta cam

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On my 82 I have the following combo:


30 off the heads and port/polish
EA82 SPFI pistons
Delta torque grind cam
EA82 intake manifold
Weber carb

New valves / rod + main bearings
Emissions delete / EGR / aux air etc.
Felpro permatorque head gaskets / OEM gaskets elsewhere


There is a little more info if you look through the thread about my Brat below. My motor is an 82 solid lifter motor. It outputs right at about 110Hp and everything clears internally, you will need 93 octane, you will want to run traditional copper core plugs with standard gap, the intake manifold will need to be ported to match the head alignment and the bolt holes will need to be slotted slightly, and you will need to manage the timing and advance curve to get the most from it. I should also say if you are building a solid lifter motor be sure to find a hydro motor cam and get that ground instead of your original solid lifter cam for proper geometry. And if you want to really port the heads (which have the most awkward flow ever) you will need to use extrusion honing which is where they pump a goo full of abrasive through the passageways to enlarge them, and then finish with traditional intake manifold to intake port matching by hand as well as the valve pocket.


Now my question is are you talking about SPFI pistons or using SPFI (Single Port Fuel Injection) in place of the carburetor? If you are talking about the SPFI pistons, then yes they will work with the specific combination I listed. If your talking about using SPFI in place of a carb, I don't know I never tried. SPFI has been proven to work great on relatively stock motors but I don't know if it has been tried on a more aggressive build and how it behaved. If I was going EFI on a build like this I would go haltech or mega so it could be easily tuned, I chose to stick with a carb to keep it period correct so the problem never came up.

And to quote General Disorder from a few years back he said;

"Of course - all of this will cost more than doing an EJ22 swap - which
is 135 HP without changing anything on the engine. And a frankenmotor
(EJ25 with EJ22 heads) is about 180 HP. You'll never come close to the
performance-per-dollar that you will find in the EJ's with a modified

Edited by subarubrat
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So I currently have 150k on my motor, waiting on a settlement from a car accident, currently a stock ea81 running spfi. I have a delta cam and 020 shaved heads and spfi pistons chilling in my bedroom. Want to get the most out of the coming ea81 head job with the parts I have. Thanks for the responses. Gd told me that changing the duration on the cam while trying to run the fi system would not work as it's pretty much designed for certain specs and not really tune able

Edited by superooo
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And not going ej, unless my 03 fozzy is totally fucked, then I already have the motor, would need everything else though. I got lots of free parts with the car, don't need a race car, just something tough and dependable. I also already have a 5sp and lsd for it, so I'm gonna stay ea I'm sure

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I'd follow what GD has mentioned to you about cam duration etc.


I made a set of solid lifters for my EA82 and was running MPFI too. Below 4000rpm it was sluggish at best, above 4000G especially with WOT, it was a screamer as far as an EA82 can be a screamer.


Problem with that is 95% of your daily driving is done well below 4G rpm with small amounts of throttle. I also wonder how it would've been with a carb setup as injector pulse timing/rate would've been a huge factor in its performance.


If you're going to build an engine, I'd recommend going with some pistons that are capable of working with some boost. Either drop a small turbo on the EA81 or put it on later, it doesn't really matter - just that I recall in my reading on the forum that EA NA pistons typically crack the ring landings after a while under boost. Food for thought ;)





Edited by el_freddo

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