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Old 04-15-2018, 06:52 PM
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Todd Burt
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Dose anyone know how much horse a stock 85 ecm can handle before it needs upgraded. I'm going to do a head and cam and rocker arm swap. I need to know if I need to get it turned. The head specs are 64 cc combustion chambers 195 intake runners 74 cc exhaust runners. 202 and 16 valves. The springs are good for 575 max lift. The cam specs are 204/215 @ .050. Advertised duration is 269/281. The max lift with 1.5 rockers is 420/442. I'm going with 1.6 roller rockers
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Old 04-15-2018, 07:10 PM
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playsdixie
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Originally Posted by Todd Burt View Post
Dose anyone know how much horse a stock 85 ecm can handle before it needs upgraded. I'm going to do a head and cam and rocker arm swap. I need to know if I need to get it turned. The head specs are 64 cc combustion chambers 195 intake runners 74 cc exhaust runners. 202 and 16 valves. The springs are good for 575 max lift. The cam specs are 204/215 @ .050. Advertised duration is 269/281. The max lift with 1.5 rockers is 420/442. I'm going with 1.6 roller rockers
I did new heads with 1.6 rockers...used the same ecm on my 85....did need to get it tuned though....

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Old 04-15-2018, 07:27 PM
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aklim
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Before I put anything in, I would strongly suggest you find a facility near you that will dyno tune. Several scenarios can happen

1. You get lucky and it runs OK, not great, OK for the most part.
2. You don't get lucky and it runs like crap
3. You are limited to whatever will run and have to stick close to stock specs.

I realize it isn't as sexy but get a tuner lined up, do intakes and LT headers that will support future mods and then ask him what cam and head combination he likes. From what I have seen, the intake and exhaust suck so even if you get the heads and cam done, you might not maximize your full potential.

PS. Why don't you fill up the profile so we know what car, your location, etc we are looking at? So if you need a tool or a recommendation, someone could actually help. You might have to buy them a beer or two though.
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Old 04-16-2018, 11:14 AM
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TheBlaster9001
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Originally Posted by Todd Burt View Post
Dose anyone know how much horse a stock 85 ecm can handle before it needs upgraded. I'm going to do a head and cam and rocker arm swap. I need to know if I need to get it turned. The head specs are 64 cc combustion chambers 195 intake runners 74 cc exhaust runners. 202 and 16 valves. The springs are good for 575 max lift. The cam specs are 204/215 @ .050. Advertised duration is 269/281. The max lift with 1.5 rockers is 420/442. I'm going with 1.6 roller rockers
Hey! I've got an 85 that is running the stock computer for about another week (swapping it out soon). It has essentially everything under the sun done to it, but was tuned before I put long tubes on it. After long tubes, the car pull harder 2.5k revs and above, but almost feels like it lost power below that. Because of that, I suspect that it needs a tune. I'm swapping computers because so few people will put up with the '85 computers, and I would like to be able to have flash tuning, like on a more modern car.

But as far as the stock computer goes, my car dynoed just shy of 400 to the wheels before long tubes, and she feels stronger now, except when under load at low rpm like I mentioned. When my car was built, it was started without a tune first, and wouldn't stay running (sputtering, coughing, dying). Based off of the info you provided, I suspect you will need a tune. The smaller combustion chambers may change how spark advance is needed. Any cam that is considerably bigger than stock will require a tune as well.

So in short: the 85 computer is capable, of at least ~500 crank hp, but you will need a tuner.
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Old 04-16-2018, 11:34 AM
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Originally Posted by TheBlaster9001 View Post
So in short: the 85 computer is capable, of at least ~500 crank hp, but you will need a tuner.
I don't think my 91 computer was capable of that much without a tune either. I'm guessing that if you go more than 10%, compensation might be tricky. My 91 F-body would start up with Accel Tri-Y headers and a Superram intake. It ran also BUT the idle wasn't the greatest and the thing had a hesitation when you hit the WOT. Ran inside the garage with the door closed and about 65-75 degrees but take it outside in the winter and it was kinda rough. Only cure was getting Lingenfelter to retune the thing and then it smoothed out.
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Old 04-17-2018, 04:47 AM
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obviously you dont trust my advice !
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