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Guest subarugsr

distributor.. what type is best for my 1972 GSR?

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Guest subarugsr

would there be any specific adjustments i could make to my distributor on my 1400 EA63? The Advance is set to 10degrees currently as per manufacturers specifications, for that distributor. Is there a distributor that could take the place of mine that would improve ignition?

 

I was also readng on the EA performence page, to bypass the vaccuum valve.. how do i do this? this is the auto advance vaccuum? do i just disconnect the hose?

 

cheers

 

Karl

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Guest GeneralDisorder

No - it's not the vacuum advance - it's a valve that only allows vacuum advance when the vacuum is high (when accelerating). With a 72, you should check to see if the vacuum advance is even working. The rubber in the diapham gets brittle, and they stop working. My 84 was toast when I got it, and it only had 150k on the car, and the rest of the car is in great shape. You can check it by reving the engine while using a timing light. Do this with the vac line connected and then disconnected - if you notice a change of like 10 degrees more with is connected, then it's working.

 

GD

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Guest subarugsr

cheers GD. i was told to time my car with the vaccuum disconnected to 10degrees, when it is connected in shoots right up past 20degrees infact quite far past it... is this alright?

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Guest GlCraigGT

some thing dosen't sound right, at idle the vaccum advance shouldn't (atleast least i don't think is should) be getting enough vacuum to advance it that much. What are you using for the vacuum source, is it up stream from the throttle plate?

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Guest subarugsr

umm yea i think it is, but im running it off twin carbi's.. does this change anything? at idle with the vaccuum advance disconnected the car idles very rough.. is this normal?

 

cheers

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Guest GeneralDisorder

As to the idle - any time you have a vacuum leak, it will idle rough. I bet if you disconnected the line, and then plugged it, your idle would come back. And yes - everything sounds good with your system - it should jump way up there 10 degrees or more (depends on the disty exactly how much). And some of that advance is due to the centrifugal advance inside the disty, so that will advance it even more.

 

GD

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Guest subarugsr

cheers GD. If i re-adjust my disty to 12degrees instead of the 10 i have it on now, will this increase horsepower?.. even be it marginal?

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Guest subyguy

sweet nice to see a gsr is still around. shoot me an email i have some q's for you. i also have some 1400 stuff that i would like to ask you about. as for the vac problem mine only works under acceleration on my 1400 (1973 wagon tailgate modle)

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Guest GeneralDisorder

Assuming it doesn't ping, take as much timing advance as you can get. The more you advance the timing, the better the engine will perform - to the point of pinging - that is when the frame-front of the burning fuel hits the top of the piston while the piston is still on the up stroke - basically, pinging means your trying to drive the engine backwards! Not good. What you want is the flame front to reach the top of the piston right as is crosses over from going up to going down. Only at that point will you recieve greatest HP, and torque. Anytime before this is a ping, and anytime after this the flame front will have to catch up to the piston, and you will have lost some power since it will slow down durring the catch-up period. Better octane fuel will not neccesarily give you the ability to advance more, as octane is the resistance to detonation, and the fuel will burn just the same if you ignite it yourself with a spark. Octane will allow you to run higher compression, and that's important on Turbo's and what not. On N/A engines, your compression doesn't change dynamically, so there is really no reason to run high octane fuel unless you have a high compression motor. In fact, it is actually BEST to run the LOWEST octane fuel your engine can stand without pinging since the lower the octane of the fuel, the more BTU's per gallon it has, and low octane fuels will burn hotter and cleaner than high octane fuels. Their resitance the detonation is lower, and thus they burn easier, and will ignite quicker and more often with a Subaru's stock ignition system.

 

GD

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Guest subarugsr

cheers GD, i will have a go at it. the car seems reluctant to perform at low revs, but once it hits round 4000rpm its off, how could i clear this problem?

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Guest GeneralDisorder

Well - your probably producing peak HP at like 4000 rpm, so it's natural that it would feel more powerful at that speed. Not really much you can do about that. If it were me, I would probably try to get a more tuneable carb on it - we like to use a Weber for our EA81's. I'm sure that the same Weber 32/36 properly jetted to your application would yeild better low-end performance. Bigger exhaust is good to a point - have to watch for low-scavenging effect if it gets too big tho. Regrinding the cam can help the engine breath better, but you will probably sacrifice driveabiliy for it. Most engines with hot racing cams don't idle so good because they run much too rich for low speed operation. If you did all this tho, you would probably end up with an engine that produces peak HP at 7000 or 8000 RPM's, and doesn't idle for beans. Great for a drag strip, but not so good for around town. Check this out:

 

<a href="http://www.ultimatesubaru.org/80s/articles/justy-lsr.jpg" target="top">http://www.ultimatesubaru.org/80s/articles/justy-lsr.jpg</a>

 

GD

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Guest subarugsr

yea the cam has been re-ground, just to standard though, it still remains as a stage one lumpy. Are twin webers possible to find and fit my car? i have had my car goin mint before but now after a couple of problems the performence at low end is realy unusual, could this be due to mixture?

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