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Stock 360 output |
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WesternRed
AMC Addicted Joined: Aug/03/2010 Location: Australia Status: Offline Points: 5787 |
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Thanks Ken.
Just did the electric fan conversion, netted a couple of tenths there. Electric pump would be the next step. How much do you think the Torker will help over the performer with 1" open spacer on a low HP engine like this and max RPM of 5,500? Intake change may tie in with a cam change at some point. Headers would be nice, but are a fairly expensive proposition in Australia, wondering whether I will see much of an improvement with bigger pipes and better muffler on the free flows? Convertor upgrade is in a holding pattern, I spoke to the local convertor shop and they want around $1300 to build a convertor for it and politely suggested that I should spend my money elsewhere first and come back to see them a bit further down the track. One of the problems is that it is an early flat crank 360 with a custom made convertor to adapt the 727, so I can't look at off the shelf convertors either.
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Ken_Parkman
AMC Addicted Joined: Jun/04/2009 Location: Ontario Status: Offline Points: 1815 |
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Did not catch that you did the fan already, sorry. Get rid of the thermostat so you can run the fan and cool the rad without the engine running. Then start the engine and circulate the hot coolant, shut it off and cool the rad again. Repeat and get it as cool as you can and try that. One thing to think of is even with a 5500 shift point the engine only drops to 3300 on the shift to 2nd, 3800 to high. So the quoted low rpm advantages of a dual plane do not apply for performance use. With a stockish converter you do need some bottom end to launch the car. But with a 10", say 3500 stall, the engine is always in it's power band. Low rpm power is irrelevant. So I'm a performance guy, so the torker is the plan as for as I'm concerned. Low rpm torque is only for scaring the wife when you roll into it on the street. But remember this is a performance discussion, not street. But on a mild engine the difference is not going to be much, maybe 10 hp. With the cost of a custom converter I'd modify the crank. But unfortunately that means taking the engine apart. For sure if you do ever take it apart modify the crank for the standard TF converter. Don't take it to an automotive machine shop, go to a quality general machine shop with the PAS drawing. Then it's cheaper as long as the guy is reasonable. A good converter has the most performance effect. You can go fast with a good converter and a taxicab engine, but a race engine with a junk converter is a dog. I've been known to run a mild $800 spare parts 401 with a top notch 8" ATI, 5200 stall, on a 6000 rpm engine. That went 10.70's in the Hornet. Would not bother me at all doing that on your engine. But once again, we are not talking street use. The problem is you can't bolt it on, and I would not get a race converter from anyone other than a reputable RACE converter manufacturer.
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billd
Moderator Group Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894 |
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Holy cow, I guess my 2500 converter is a toy, then. LOL, oh, well........
Keeping my eyes on this as I have a 360 in my 73. The engine leaks oil, etc. so it may get freshened up some year so watching these results for budget tips. My next step is a different ignition system - it's still stock, in an almost 400 HP engine. |
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WesternRed
AMC Addicted Joined: Aug/03/2010 Location: Australia Status: Offline Points: 5787 |
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Plenty to consider, I did pick up a spare late 360 crank to use down the track if I decide to freshen the motor and that would resolve any convertor compatibility issues.
Torker is sitting on the shelf, so that could certainly go on. If I put the XE262H in with some new valve springs, that might give me a bit more RPM capability too. |
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PacerLarry
AMC Apprentice Joined: Aug/02/2010 Location: New Lenox, IL Status: Offline Points: 103 |
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My car is set up pretty close to what you have. I have a 904 not a 727, but when I changed over to a manual valve body, I picked up between 3 and 4 tenths with no other mods. I only shift at 5500 because the car falls off above, but with the factory valve body, I would always get a flare up on the 2-3 shift.
A local guy that runs stock eliminator told me switching to radial slicks (different than drag radials) was good for a tenth on his car. Another trick to get your ET down is using the tallest front tires you can fit and staging as shallow as possible.
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Ken_Parkman
AMC Addicted Joined: Jun/04/2009 Location: Ontario Status: Offline Points: 1815 |
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Another advantage of a good converter is you don't have to rev the engine so high. The problem with a low stall, say 3500, is the engine drops all the way to the transmission input speed on the shift. So you drop way out of the max power range, so you have to badly over rev the engine to make the car quicker. With an 8" converter then engine does not drop on the shift so it stays at max power, the converter has a delta rpm so it goes back into torque multiplication, and you get way more power to the rear wheels. The trick is to keep the engine in it's power band, not above or below, for the entire pass. That's why a car with a race converter goes faster with a lower shift point.
Go faster and easier on the equipment - what's not to like? So obviously I vote for the good converter. But I have to stress the importance of the word "good". I've had a junk converter eat 100 hp. It had the stall, but not the design. And since most people (me at the time) don't understand how important it is they only look at stall speed. If someone has been in there bending fins to mess up the converter efficiency and get an artificially high stall it's a piece of junk. I spent a whole summer trying to find my missing power in the engine, when all along the engine was fine and the converter was junk. So go to a reputable RACE converter manufacturer. And if the diameter if wrong for the application run away. |
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WesternRed
AMC Addicted Joined: Aug/03/2010 Location: Australia Status: Offline Points: 5787 |
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Thanks, that the sort of info I was chasing regarding the valve body change, if I can pick up 2 tenths with that, I'm in the 13's. Valve body is sitting here gathering dust so it might as well be in the transmission, bought it off a mate who upgraded to a trans brake. Ken Parkman, you are preaching to the converted. The things holding me back on a convertor change are the cost for a good one (that's a biggie), the stupid flat crank in my motor and the thought that if I get something that is optimised for what I have now, then it probably won't be optimal if I make other upgrades down the track and I might have to spend the money twice. Might be something to think about more over the winter break (it's summer here at the moment). PS: The current convertor stalls at around 1400. Edited by WesternRed - Feb/21/2018 at 7:00pm |
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AMC instigator
AMC Addicted Joined: Sep/13/2009 Location: Cook Minn. Status: Offline Points: 1264 |
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Sounds like you have been slowly working in the right direction. I have seen some great suggestions, from some very good racers. I'll just add a few. You might try airing up the slicks to 20 and run it, then add a psi each time time it wont hook any longer. 10 inch slick is wider than you need so it creates scrub. The Torker is better. A 1" 4 hole spacer will give it better throttle response with your stock convertor. Do not "stall" up the convertor, leave off a dead idle, and hammer the throttle, it will stall a bit more, bringing the 60 down. The timing works fine on a low compression stocker at 20 initial. I have a couple at 22,and a total at 42, and run them that way. If you get a chance for a distributor tuning kit, set the initial with the old tight springs at 20, then install and use use one lightest spring, and one med. This will bring it in right on for your 360 and 4:10. You must set the initial with tight springs, the weak ones will bounce. Or you can set it at 3000 using your total of 40. Vacuum advance is no longer hooked up or used. So you are aware the manifolds are holding back 3 tenths. No problem, but I figured you would like to know cheap headers would gain that without issue. The 262 cam you have is too small. It would be best to leave what you have, or put in a 270H Comp, providing your leaving the convertor. If however you install the convertor Ken P suggested install a 280H Comp. Don't worry about the compression and the cams, it will make you smile. The tips you have gotten on this thread from many good racers will make the car turn 13's without much more than a few adjustments, and low 13's with a cam and header install, the good convertor as well, that's 12's. That is with 8.5 compression. Hope that helps SH
Edited by AMC instigator - Feb/22/2018 at 12:57am |
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wantajav
AMC Addicted Joined: Sep/04/2009 Location: PA Status: Offline Points: 1150 |
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Has this been suggested? Going to the smallest lightest rear tire /rim combination you can run without excessive spinning to get a quicker shot off the line. Maybe you don't need a 10" slick with this car.
Thinking a smaller rear tire would also be like running a slightly higher (numerically) rear gear ratio. Less wheel/tire inertia to overcome as well. Great reading , really enjoying this thread!
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WesternRed
AMC Addicted Joined: Aug/03/2010 Location: Australia Status: Offline Points: 5787 |
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The 26" slicks on there at the moment are pretty small diameter in the scheme of things unless I want to drop down to a 14" wheel. Being 10" wide is definitely overkill though, but they were cheap and look cool. Will definitely look at other options when they wear out. Probably better served by running drag radials, but the slicks are actually quite lite in comparison. I also have to be a bit mindful of terminal speed since I can't rev it to 6,000 or 7,000 RPM.
Interesting thoughts on the cam SH, I was originally thinking 280H, but was talked out of it due to the lack of compression. The XE262H is pretty close to the 270H, slightly smaller on the intake and slightly bigger on the exhaust. The really good thing about last time I ran it, was that I was getting pretty consistent times, so I will have more confidence in making small changes at the track. Previously the times were so inconsistent that it would be hard to tell if something like a small timing change made any difference. One of the aims with this car was to get a lot more seat time so that the driver can get tuned up as well.
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