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| Help slantsix.org you're my only hope https://slantsix.org/forum/viewtopic.php?t=41956 |
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| Author: | 73NorthernDuster [ Sun Sep 19, 2010 8:18 am ] |
| Post subject: | Help slantsix.org you're my only hope |
Ok guys Iam having a bad week....... I spent the last five years rebuilding my 73 Duster. I rebuilt the engine with performance in mind 75 off head 2bbl upgrade, 6al box, good wires, cap,rotor, isky cam (that was one tooth off from specs when I degreed the cam). Motor runs pretty good but does not have the power I expected. I can't even get it to break loose the tires and it only gets about 18mpg on the hwy. I took it for a long trip about 1000km and checked the oil it was down a quart...seem a lot on a rebuilt engine (yes or no)... Out on the road the car picks up good and seems to pull forever but like I said off the line its a dog...a big fat one....I am thinking distributor recurve but I wouldn't know where to start...Ive studied all the threads, look at the manuals took apart my old dizzy....my head is spinning with too many variables.....Or maybe it's the stock converter holding me back...Help me obi wan your my only hope before my friends try and sway me to the dark v8 side.... One says there is a brand new 318 crate engine that was expropriated from the massy ferguson factory back in the 70's and was destined for a combine...a 318-3, and has been sitting in a barn for the last 35 or so years still wrapped and in its crate.........all for 150.00....it has got me thinking....... |
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| Author: | Charrlie_S [ Sun Sep 19, 2010 9:04 am ] |
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Need more input. What is the compression ratio, or amount milled off the head, if any. What are the cam specs, and what was it degreed at? What do you have for exhaust. If the engine is not broken in, yet, I would not worry about the oil consumpion, yet. It is possible you need a distributer recurve, but give us the other info first. As for the 318, I would get it. Not to replace the slant, but for a different projet, or to sell or barter for other parts. That sounds like a good deal. |
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| Author: | slantzilla [ Sun Sep 19, 2010 9:50 am ] |
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What are the specs on the cam? Auto or stick? Rear gear? Stock converter? How much power did you expect? Reality is you still have a 2bbl Slant in a fairly heavy car. |
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| Author: | 73NorthernDuster [ Sun Sep 19, 2010 12:19 pm ] |
| Post subject: | More specs |
Ok Engine went 20 over and 10 10 on the crank. I removed the egr and blocked it off. Cast iron 2bbl intake, msd 6al, blaster coil, good plug wires, Cam Isky 256/256 lift .425/.425 degreed to cam specs for open/close but I found it off one tooth on the timing chain when I degreed it. I think it was 1 tooth retarded..I tried 2 different timing sets and both were the same. Rear 8.25 with a sure grip 3.21 gears Trans 904 with a shift improver kit. Internals from a sb 904, stock /6 converter. Head has .075 milled off for 9.1 compression. A thin metal shim head gasket was used. put oversize valves in the head and a good valve job. new valve seals, 340 springs Exhaust dutra dual up front with modified stock manifold. running 2" pipe all the way back to thrush hushthrush mufflers...still way too loud. (a real buzz at about 2500 rpm... Carb is a holley reman (ya I know reman) Carter bbd (could be the problem) Dizzy is the only place I don't know what internals are in it... I've seen other guys builds and they break the rears loose with no problem. I think it maybe just needs a little fine tuning, either dizzy or carb, but there are no other slant guys I know of close by to pick their brains. My two buddies have bb cars....they are jealous of my 18-19mpg though... |
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| Author: | Charrlie_S [ Sun Sep 19, 2010 12:29 pm ] |
| Post subject: | Re: More specs |
Quote: Ok
But what are the numbers? intake open/close, exhaust open/close? That is actually a mild cam.
Cam Isky 256/256 lift .425/.425 degreed to cam specs for open/close but I found it off one tooth on the timing chain when I degreed it. I think it was 1 tooth retarded..I tried 2 different timing sets and both were the same. |
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| Author: | DusterIdiot [ Sun Sep 19, 2010 12:44 pm ] |
| Post subject: | Bushing? |
Quote: I think it was 1 tooth retarded..I tried 2 different timing sets and both were the same.
So did you get a bushing kit and put the cam on the spot, or put some advance to it?I think a recurve is in order here for sure. That cam is pretty mild...with a little less lift than the MP243 cam and Comps 252 cam... -D.Idiot |
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| Author: | 73NorthernDuster [ Sun Sep 19, 2010 2:16 pm ] |
| Post subject: | Cam a .050 |
I had two different cam charts for my cam thus my confusion in degreeing it at the time. I didn't use a bushing kit or anything just installed 1 tooth retarded to get to one of the specs. 1st chart: duration 210 intake open -7 btdc close 37 after bdc exhaust open 37 bbdc close -7 atdc lobe center 112 overlap 32. these are the specs I intalled to 2nd chart intake open -1 btdc closed 31 abdc exhaust open 43 bbdc -13 atdc...everything was off by 6 degrees. I should have sent the thing back to isky they had the worst customer service ever. I ordered a kit with cam lifters,rods, springs and retainers. push rods were for a 170, springs were way too high and the aluminum retainers my engine builder said were no good on a street car. They wouldn't send me the right rods or springs...That being said it reminds me I have some isky 170 push rods if anyone needs some.lol |
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| Author: | Charrlie_S [ Sun Sep 19, 2010 4:04 pm ] |
| Post subject: | Re: Cam a .050 |
Quote: I had two different cam charts for my cam thus my confusion in degreeing it at the time. I didn't use a bushing kit or anything just installed 1 tooth retarded to get to one of the specs.
It has been a long day, but if I am running the numbers correctly, I would have used the 2nd chart numbers. That would put the cam at 106 degrees centerline. Most slant sixes like the cam on the advanced side. Depending on the cam, many of us run the centerline between 100 and 108. From your description, I think the cam is too far retarded. 1st chart: duration 210 intake open -7 btdc close 37 after bdc exhaust open 37 bbdc close -7 atdc lobe center 112 overlap 32. these are the specs I intalled to 2nd chart intake open -1 btdc closed 31 abdc exhaust open 43 bbdc -13 atdc...everything was off by 6 degrees. That being said it reminds me I have some isky 170 push rods if anyone needs some.lol PS: there are 38 teeth on the cam gear, so jumping one tooth will change cam timing approx 9.5 degrees. PPS: I might be interested in the pushrods, depending on price and the style of the PR |
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| Author: | Doc [ Mon Sep 20, 2010 9:00 am ] |
| Post subject: | |
I think you need to re-check your cam's position. You can do a preliminary chack by pulling the vlave cover and seeing how "centered" the ovelap event is at TDC Ex. DD |
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