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PostWhore, The AFDB is on a lil tight.
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Discussion Starter #1
I just added 373 TL to my 94 which was already tuned for a 02 gt mafs, 2800 stall tc with a built trans and 98mk 1 piece DS. The engine is stock as is the exhaust. No plans to touch the engine.

Would you think a retune is in order?
What is the max limit I can rev my stock 4.6 engine without blowing it up? And does running synthetic mobil 1 allow you to rev it higher?
 

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Confirmed V6 Nut
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What were your old gears? 3.08s or 3.27s?

Unless you're going to build your engine, I wouldn't rev it beyond the factory rev limiter.
 

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PostWhore, The AFDB is on a lil tight.
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Discussion Starter #3
What were your old gears? 3.08s or 3.27s?

Unless you're going to build your engine, I wouldn't rev it beyond the factory rev limiter.
you mean at like 6200 rpms LOL. it came with 327s stock.
 

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Confirmed V6 Nut
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You might ask that question in EEC tuning, but that is 2 gear steps. My car did alright going from 3.27s to 3.55s, but I put that into my splitport tune.
 

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I just added 373 TL to my 94 which was already tuned for a 02 gt mafs, 2800 stall tc with a built trans and 98mk 1 piece DS. The engine is stock as is the exhaust. No plans to touch the engine.

Would you think a retune is in order?
What is the max limit I can rev my stock 4.6 engine without blowing it up? And does running synthetic mobil 1 allow you to rev it higher?
"98 Mark VIII 1 piece DS".... NOT. :tongue:

I'm with PCD, I wouldn't go much above the stock rev limiter. But unless you take it to a dyno and look at the curves, the point is moot. I wouldn't mess with rpm on a stock 94 4.6L. After H/C/I, then yeah.

But just my .02. :thumbsup:
 

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PostWhore, The AFDB is on a lil tight.
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Discussion Starter #6
"98 Mark VIII 1 piece DS".... NOT. :tongue:

I'm with PCD, I wouldn't go much above the stock rev limiter. But unless you take it to a dyno and look at the curves, the point is moot. I wouldn't mess with rpm on a stock 94 4.6L. After H/C/I, then yeah.

But just my .02. :thumbsup:
So basically don't ask for more out of an emailed tune than I am already getting? It drives fine without any complaints at this point. Yeah its a 93 DS LOL

And I don't drive it where I red line it, I did it a total of twice where I reved past 6 k jsut to see what it would do and it chirps the tires no problem. The rev limiter has been upped for sure. What have people taken their stock 4.6 up to?
 

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If you are running a stock driveshaft, which is anything other than the fairly rare early-93-Mark-only one-piece driveshaft, high RPMs will kill them fast.

They're two pieces of sheetmetal, with rtv squirted between them.

Replace it first.

BTDT. :)
 

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From the engine-only standpoint......All stock you say? I think if you stay with the factory-set limiter at least your rods will thank you.

And does running synthetic mobil 1 allow you to rev it higher?
No. Stronger and lighter pistons, rods, crankshaft, valves, valvesprings, and cams, intakes, exhausts designed to take advantage of all that do.
 

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PostWhore, The AFDB is on a lil tight.
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Discussion Starter #9
If you are running a stock driveshaft, which is anything other than the fairly rare early-93-Mark-only one-piece driveshaft, high RPMs will kill them fast.

They're two pieces of sheetmetal, with rtv squirted between them.

Replace it first.

BTDT. :)
I already posted I have a 93 mark shaft yeah my 2 piece was garbage 2 years ago.

I'm just going to watch myself its not really that hard to not rev it that high, I just was surprised it did roar to 6k being stock and how hard it shifted. I have to make this engine last a couple years more. What is the stock rev limiter set at?
 

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I just added 373 TL to my 94 which was already tuned for a 02 gt mafs, 2800 stall tc with a built trans and 98mk 1 piece DS. The engine is stock as is the exhaust. No plans to touch the engine.

Would you think a retune is in order?
What is the max limit I can rev my stock 4.6 engine without blowing it up? And does running synthetic mobil 1 allow you to rev it higher?
Not to 'jack the thread, but where did you get your 3:73 TL? I'm getting ready to do the same to my 95.

Mike
 

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6k rpm!? and everyone told me 5500 rpm was to high for my modded motor. the other day i took her out for a spin to show my friend and second gear spun all the way to 5700rpm i was like Oh Sh!t

mine chirps the tires easy at 4k rpm when its dry :) and spins at 5500rpm. its boss :D
 

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First off, the driveshaft has nothing to do with how high you can rev your motor. The driveshaft turns at the speed of the output shaft of the trans, so in first gear a 7K rpms, your driveshaft will still be turning slower than 4th gear at 2500.

As for the rev limiter on the motor, I don't know if you will get much out of it by revving it higher, but my understanding was that the rev limiter was there more to protect the torque converter from ballooning than to protect the motor itself. When I had my 5-speed 94 cougar, I used to wind that out to 6K at pretty much every stop light, and nothing ever blew up from it, and that was on a motor with about 230K miles on it. My 5-speed MarkVIII will easily rev to 7K, but I have been told that is bad for the cast crank, so I try to keep it to 6500. Considering the MarkVIII still has the same cast crank and rods that the 2V motor has, and it got a 6K rev limiter from the factory, I would say with your upgraded converter, you should be perfectly safe up to 6K, but with a stock 94 2V 4.6, there probably isn't much gain to revving it that high anyway.
 

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I just added 373 TL to my 94
First off, the driveshaft has nothing to do with how high you can rev your motor.

my understanding was that the rev limiter was there more to protect the torque converter from ballooning than to protect the motor itself.
The gears will make the driveshaft spin faster than stock, and kill it faster. See the article on critical driveline speed for reference.

Stock TCs ballooning is given as the reason for the 5500 stock limit, but I've never personally seen a broken one. I have aftermarket converters now, tho.

You need smaller diameter aftermarket with anti-ballooning plates for over 5500, unless you want to break some stuff.

Something like this:
http://www.dirtydogperformance.com/converters/ford/4r70w-/-aode/10-inch-4r70w/prod_10.html
 

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PostWhore, The AFDB is on a lil tight.
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Discussion Starter #16
I plan to get a much nicer DS in a year or so. THe mark one will have to stay until then, its a solid unit and was balanced just to be sure about it.

Alan how high in revs did you take your engine up to get that 14.22 pass?

So basically the best thing for me to do is have it dyno tuned, yeah?
 

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I plan to get a much nicer DS in a year or so. THe mark one will have to stay until then, its a solid unit and was balanced just to be sure about it.

Alan how high in revs did you take your engine up to get that 14.22 pass?

So basically the best thing for me to do is have it dyno tuned, yeah?
It was 14.55 and I shift at 5800. The only thing my car has is a 60ft of high 1.8-low 1.9 I seriously have no power and on the big end you can feel it. Hopefully by the shootout this year I should have a teksid shortblock with PI heads installed as a "temporary" engine using all OEM components. I am saving the forged shortblock I built until I can afford every piece I want in it.
Alan
 

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The gears will make the driveshaft spin faster than stock, and kill it faster. See the article on critical driveline speed for reference.

Stock TCs ballooning is given as the reason for the 5500 stock limit, but I've never personally seen a broken one. I have aftermarket converters now, tho.

You need smaller diameter aftermarket with anti-ballooning plates for over 5500, unless you want to break some stuff.

Something like this:
http://www.dirtydogperformance.com/converters/ford/4r70w-/-aode/10-inch-4r70w/prod_10.html
Yes, gears will make the driveshaft spin faster...at a given vehicle speed, but it has no effect on how high the engine can rev. If you're driving at 60mph, and you drop your car down to 2nd gear, the driveshaft is still spinning at the same exact speed, even though your engine will now be screaming. Changing to 3.73s will be harder on the driveshaft if you consistently drive at 100mph, but like I said before, the rear gears and the driveshaft have absolutely no effect on how high you can safely rev the engine, only on how fast you can safely drive the car.

As for the torque converter ballooning, I have never seen a broken converter, but I have seen cracked flywheels from them ballooning. When you pull the trans out of a car that has a stock converter and has been over-revved, you can actually see imprints of the flywheel bolts on the front of the converter because as it balloons, the center expands and pushes against the crank, hard enough that you can acutally see the markings on top of the bolts, imprinted into the front of the torque converter. Since the center of the converter is pushing on the crank, and the edges are expanding outward, it can crack the flex plate right around the outside edge of where it bolts to the crank. But since he said he already has a 2800rpm converter, I am assuming it is not the stock unit, and will be fine up to at least 6K, since the stock ford 4V converters were fine to that rpm.
 

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Yes, gears will make the driveshaft spin faster...
I wasn't disagreeing with you, just posting why I said that.

So, divots in the front of the converter first; I'll have to look for that. :)

I understand that in severe cases the crank can get pushed far enough to break...
 

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Since the center of the converter is pushing on the crank, and the edges are expanding outward, it can crack the flex plate right around the outside edge of where it bolts to the crank.
+1 I have seen this happen several times and personally broken 3 flexplates on my Chevelle this way.
 
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