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Guest Message by DevFuse
 

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cam shaft difference in the EA-82?


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11 replies to this topic

#1 svxpert

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Posted 05 October 2003 - 08:25 PM

while tearing down my EA-82T and EA-82N/A engines, I was wondering if there was a difference (in HP) between the two engine's camshafts. I checked my parts book and there is a difference in part numbers. I am in the process of building a EA-82T from a N/A shortblock and turbo heads and trying to put on a spider intake manifold. I was wondering if the 2 different cams will give me any extra HP? thanks in advance.

#2 carfreak85

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Posted 05 October 2003 - 08:37 PM

turbo cams are for turbo engines and NA cams are for NA engines. they have different grinds that are turbo and NA specific, so by using a NA cam on a turbo engine, your valve timing will not be optimal.

#3 svxpert

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Posted 05 October 2003 - 09:08 PM

thanks for the info. i was just trying to squeeze some more hp from my engine.

#4 archemitis

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Posted 05 October 2003 - 09:14 PM

na cams in a turbo might be cool. better low end torque? faster spoolup?

#5 ByTheSea

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Posted 05 October 2003 - 09:37 PM

For what it's worth that might be a really BAD idea. The main difference as I recall was in overlap with the turbo having more duration. If you are forcing in the charge you'd want the exhaust valve closed sooner else it would just blow a lot of the F/A charge straight into the downpipe. Turbo cams will work in a N/A motor but the low end is very anemic. I have a set in my N/A motor and while it romps at very high RPM it isn't what I'd call a positive result overall. I'm only still using them because I plan to supercharge.

#6 GLCraig

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Posted 05 October 2003 - 10:09 PM

Believe it or not, EA82 carb and turbo share the same cams. Here are some specs from an 86 FSM. SPFI and MPFI are different.

Posted Image



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#7 subynut

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Posted 05 October 2003 - 10:52 PM

Sorry if it's a little off topic, but I'm curious. What would B the better setup for my EA82 w/weber? Me's engine needs a rebuild and I was wondering which cam would be the better bet? SPFI? or MPFI w/o turbo?
Almost looks like maybe the whole SPFI head would B the best setup. No yes:cornfuzz:

#8 asavage

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Posted 06 October 2003 - 12:07 AM

Originally posted by GLCraigGT
[B]Believe it or not, EA82 carb and turbo share the same cams.


Huh?
The 1st pic shows very different valve event timing for the two. Or am I missing something?

The 2nd pics shows identical lift.

In general, turbo cams have reduced overlap.

#9 GLCraig

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Posted 06 October 2003 - 01:31 AM

The 1st pic shows very different valve event timing for the two. Or am I missing something?



I think you're reading the MPFI Non-Turbo column not the turbo column. Also the info in the second pic show that carb and turbo have the same identification marks.

#10 RedRX

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Posted 06 October 2003 - 01:52 AM

Ouch - i have an EA82T that was built up for rally work in my RX. Pulled the lifters to fix the rattle and loosen up the locked ones - noticed the huge off-set cirlces it has for cams andf the markings on them (not regrinds - but from real chunky billet) 30-70 70-30. I guess this explains why I have no low-end?

#11 ByTheSea

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Posted 06 October 2003 - 11:49 AM

Maybe I'm thinking something else here. I just swapped a cam in a 89 Ea-82 from a 3AT 4WD and the marking was a 7 I think. My turbo cams are 5(I may be getting that backwards). I'll look at the one on the shop bench today as I'm now curious. Did the specs change in the later years? Also are the carb motors lower HP than the spfi? Is that all from the compression or is part from that cam profile?

#12 MilesFox

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Posted 06 October 2003 - 06:06 PM

i had turbo cams in a spfi motor with a carb. had good low end with open ports, pulled a 2 axle trailer with a dead soob, but was a dog turd with an exhaust pipe!




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