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EA 71. Building a rally engine and gearbox. I need some help.


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I would like to build an EA 71 rally engine for competition use in VHC.

 

To be noted that accordingly to the F.I.A. homologation form of the Leone of 70s(A22L,A31L,A32L,A33L,A26L)are permitted only the EA 63 and EA 71 engines.

 

Because of those types of engine are very rare,here in Greece,I would like to collect all possible infos,experiences,suggestions,etc, before starting building it.

I have in mind to machining the intake ports of the heads to accept twin WEBER carbs,one twin on each head.

 

I would like to know,also,if the EA 63 heads are most preffered than those of the EA 71 ones.

 

Furthermore I would like to know in what models I could find 5gear gearbox,compatible with the EA 71 engine.

 

In the F.I.A. homologation form of the time I saw that there is 5gear gearbox with the following ratios:

1st   : 3.31 (43/13)

2nd  : 2.53 (38/15)

3rd   : 1.96 (45/23)

4th   : 1.52 (41/27)

5th   : 1.03 (35/34)

 

and final drive(CWP) : 4.13 (33/8).

 

Could i found those ratios in some model?

Edited by 1000 Pistes
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what type of 5speed gearbox(from what model) I could mount on the eA 71 engine,always for FWD car?

A Subaru gsr(coupe) 1.4 or a GFT(2 door hard top) or GFTS 1.4

 

I'm not sure what model, but you might ask this person what the chassis tag says the gearbox is:  http://saojuliaofigueiradafoz.olx.pt/subaru-gsr-1-4-1975-iid-444508251

Edited by Legacy RallyGuy
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In Australia the GSR only ever came with a 4 speed gearbox, only the hardtop was equipped with the 5 speed. Very rare transmission as not many hardtops would have been sold and certainly not many have survived!

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When the Vintage Subarus roamed the planet, the majority of the country adopted the 55 MPH Speed limit was in place across the US (signed into law in 1974).

Automotive Manufacturers then built, powered, and geared for the new National speed limit. Making engineering changes that brought maximum efficiency at anything below 55 MPH. Bursts of speed were factored in, but sustained and prolonged running at those speeds was not considered.

Anything over 55 is considered "Overspeed conditions" for any vintage vehicle (such as our little Subaru). American vehicles seem to be able to hold up better, but Foreign imports would be up on the current vehicle requirements and would have built to the legal standards of the day.

Wear and tear accelerates at our current freeway speeds.

(75 MPH on the interstates here, with 85 accepted in some of the Southwestern states)

a 1970s vintage Subaru running an EA71 through an automatic or a fourspeed would be SHRIEKING at those speeds.

Yes, it could do it...but I doubt it would hold up for any length of time. (and FORGET about your mileage figures being anything other than horrid)

 

Now the question,

Is there a regear kit or an overdrive available?

Not that pushing an EA71 to power such tall gearing would be any advantage.

Granted, we run "outdated" vehicles that have been superseded many times over.

Still, any ideas of anyone has been tinkering in this area?

 

inquisitively,

Timothy

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