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EA82T cam question/timing

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The 85-86 EA82T likes its timing at 25deg BTDC.. and the 87+ Ea82T likes it at 20deg BTDC. What causes the difference? is it the cams or the computer????

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compresion is same. Its the electrical systems that are different. THe Engine control system is way different on 87+ cars as opposed to 85/86 cars.

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will the intake harness be compatible with the 87 mpfi, as if i were to put an 86 motor into my 87 turbo wagon, and use the 87 distributor?

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Generally not, as the harness on the intake manifold will have different plug ends. However, I recently saw an early 87 that had 86 style plug ends on it

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yes.. the 87 and up EA82Turbos came with a different cam.

 

You ever driven a pre 87 motor, and a 87 and up motor?? Ever notice that the 87+ motor will pull to like 7,000 rpm when the pre 87 motor runs out of steam at about 5,000rpm??

 

it's a different cam. The pre 87's had basically the same cam as the N/A cars. However the newer motors has a cam made for the turbo.

 

Drive one...then you'll believe me

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note the cars in the sig.

 

I have both. Both acted the same. The GL-10 runs out, as of now, and before mods, at 5500. The RX runs out at the same, stock. WIth some mods, at 5500. With ALL mods, it runs out at 8k...or sometihng like that.

 

No trying to bash you, but Ive ridden in another RX, with intake and exh mods, and it runs out at 5500~6000 as well. Its an 88.

 

Granted that STOCK...an 86 vs an 89, the 86 runs out at 5k more so than the 89...but still, past 5500 of the cars Ive experenced...they are done for, STOCK.

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On N/A cars, were there also different cams offered?

 

If so, which one is the the best?

 

When I rebuild my engine, I have the choice of cams from the original '86 carbed engine, the unknown-year carbed japanese import engine that I will be yanking out, and the '89 SPFI engine in my parts car.

 

Also, same question for the heads. Are there any differences between different years of carbed engines or between carb and SPFI?

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unngh. so should i be running my 1987 EA82T with 1986 wiring/dist/computer at 20degBTDC instead of 25deg?

 

 

I get some ping with my foot REALLY into it but i though maybe i'd need to advance it past 25deg and up the octane, as I have the airbox cut out and a 2.5" catless exhaust.. but maybe it's advanced too far?

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Id be running the timing as far adavanced as possible with out haveing detonation, and always run the highest octane avalible for any turbo car.

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Just for comparision, 87 hot wire 5 speed

I have my distributor ignition timing adjustable from the dash and run mid grade, tweak as nes. 26 MPG

Run about 25 BTDC as a norm.

Have tried high test- no change that would warrent the expense.

14 PSI w/ B.cut, IC, very open in and out "takes" + other mods, &

still get creamed by ricers.

Me thinks

a) I have some hi tech rockets runnin' around in Civic/Integra/Eclipse bodies

B) you guys that say you waste them all the time, have some "sticker specials" you are running against.

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down here, the rice cars that prowl the street are sticker cars, stockers with rice intakes and exhausts.

 

There are lots around here tho that have real power. Some supras, one 2.5 RS Turbo, and a handful of Civics and 240s that are turbo'ed. Those dont prowl the streets for some reason. It seems the real power cars dont get caught on the street, while the riceboys and their riced up cars are always out looking for trouble.

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