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ea81 turbo heads


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Anyone know if ea81 turbo heads are any better(valve,ports,etc) than n/a heads. Got an 85 brat and getting a parts car with a bad ea81 turbo motor and I was thinking about making my n/a motor fuel injected using the heads,mainfold and stuff from the other motor. Would be even better if the heads have more flow than the n/a heads. Assuming the heads are still good still anyway.

 

Would rather do the multi port with the weird injectors in the head than a spfi off an ea82, or weber conversions. And if I get it all running would be easy to stick a turbo back in there again since I have the uppipe and stuff, just need another bottom end or rebuild the old one.

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Would rather do the multi port with the weird injectors in the head than a spfi off an ea82, or weber conversions.

 

Why? You would need a custom injection computer (Mega-Squirt, etc) as the EA81T's MPFI is niether set up to run without the turbo, or set to run with the high compression of the N/A block. The heads really don't flow all that much better - the exhaust port is still siamesed. Plus the EA81 MPFI uses the old flapper-door MAF.... which just plain sucks. Your mileage with the stock ECU will suck.

 

SPFI is the way to go - it's the cheapest and quickest way to FI, and it's simple and rugged. With Mega-Squirt you could easily upgrade the TB if you so desired.

 

GD

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It is my knowledge that the Turbo heads are the exact same as the larger valved EA81 heads. Only difference is the injector bosses.

 

You could run the EA81T FI setup without the turbo. The computer doesn't care. However, it is a much more primitive FI setup than the SPFI. Flapper MAF vs the Hotwire MAF, doesn't have a comptuer controlled idle valve (The AAV is controlled by the temp of the coolant), the throttle sensor doesn't have a pot, so there's no accel/decel enrichment, etc.

 

The only advantage is you can run more fuel through the system because the 4 injectors can flow more than the single injector from an SPFI.

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The only advantage is you can run more fuel through the system because the 4 injectors can flow more than the single injector from an SPFI.

 

I'm not so sure about that - remember the SPFI EA82 is 90 HP and the EA81T is still only 95. The EA82 is rated for higher RPM as well. The SPFI may have only a single injector, but it's BIG. It's hard to say without flowing them exactly what the params are - the EA82T injectors aren't large enough for many folks that want to use FPR's.

 

GD

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Why? You would need a custom injection computer (Mega-Squirt, etc) as the EA81T's MPFI is niether set up to run without the turbo, or set to run with the high compression of the N/A block. The heads really don't flow all that much better - the exhaust port is still siamesed. Plus the EA81 MPFI uses the old flapper-door MAF.... which just plain sucks. Your mileage with the stock ECU will suck.

 

SPFI is the way to go - it's the cheapest and quickest way to FI, and it's simple and rugged. With Mega-Squirt you could easily upgrade the TB if you so desired.

 

GD

 

Well since its set to run a turbo, which would make the actual comp ratio much more than that of the "high compression ratio" of a n/a motor. It would run it. Just not optimally without the turbo.

 

It can be done.

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I can give you a 100% guarentee that if the short block of that EA81T is bad that the heads have cracks between the valves. And they are probably big ones.

I was considering this mod a long time ago and decided it was to much work for little improvement.

Go the EA82 SPFI if you want the FI.

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I'm not so sure about that - remember the SPFI EA82 is 90 HP and the EA81T is still only 95. The EA82 is rated for higher RPM as well. The SPFI may have only a single injector, but it's BIG. It's hard to say without flowing them exactly what the params are - the EA82T injectors aren't large enough for many folks that want to use FPR's.

 

GD

Yeah, and you wont need more fuel anyway, since it doesn't sound like you have plans to increase airflow... I'm not sure by how much, but non-US models seem to have a higher power output (particularly the turbo ones), so the stock injectors are large enough for a wee bit more anyway...
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Yeah, and you wont need more fuel anyway, since it doesn't sound like you have plans to increase airflow... I'm not sure by how much, but non-US models seem to have a higher power output (particularly the turbo ones), so the stock injectors are large enough for a wee bit more anyway...

 

We have to conform to stricter emmisions standards, even back in the 80's.

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