Correct me if I'm wrong.... (Torque Converter Questions)

[JLHARVEY1]

To the best of my knowledge, the Mach 1 uses pretty much the same engine as the Marauder. I hear that manual tranny Mach 1's max RPM is 7000 opposed to the Automatic and Marauder's 6000 RPM. I understand this is because the torque converter can only handle 6000 RPM. Is this all true? If so, with an aftermarket torque converter can we safely raise the rev limiter to 7000 RPM?

Also, I have a good understanding of torque converter stall speeds, but beyond that speed is an aftermarket torque converter beneficial? Is it more efficient at transferring the power to the axle. Or is the higher stall speed the only real benefit of an aftermarket torque converter?

[LincMercLover]

It's true that the TC is what's holding the motor back from reving into the 7000's. This is due to "ballooning" of the TC at high rec speeds. Now, the question is, is there any power to be made there in the 7000 range... I would say there isn't, seeing how the peak HP is coming in at 5750RPM. Granted, this is an OHC motor, but 7000 RPM is not something I want to hear my V8 hit. So yes, the only benifits from an aftermarket TC is the raised stall speed.

[JLHARVEY1]

Thanks for the info... I didn't really think there would be much of an advantage of going much beyond 6000... Mostly just curious.

[rurumon]

Originally posted by LincMercLover
It's true that the TC is what's holding the motor back from reving into the 7000's. This is due to "ballooning" of the TC at high rec speeds. Now, the question is, is there any power to be made there in the 7000 range... I would say there isn't, seeing how the peak HP is coming in at 5750RPM. Granted, this is an OHC motor, but 7000 RPM is not something I want to hear my V8 hit. So yes, the only benifits from an aftermarket TC is the raised stall speed.

What about that link that posted a peak torque at 6200 rpms?

here it is...


Is this BS? This is definately a reputable site, and it clearly pointed out that there was power higher up.

http://www.mercurymarauder.net/forums/showthread.php?s=&threadid=3869

[cyclone03]

I think the DOHC engine has TWO HP peaks.
That Dyno chart IMO IS a MACH 1 chart.

Watch out this may get deep,
is there power above 6000rpm?
I don't know,but by being able to rev above 6000 you may be able to use the extra rpm to adjust the shift points for better acceleration.
In a perfect world you want to shift at the HP peak and have the rpm,after the shift,drop to the torque peak.Now the spacing between the transmission gears may not be the same so each gear change may need a different shift point,higher or lower.

Let's say the HP peak is 6000prm and the torque peak is 4500.
The 1-2 gear change hits right at 6000 but the after shift rpm drops to 3800.This is below the torque peak,so what you feel is a lag after the shift.So we readjust the shift rpm to 6700 now the after shift rpm hits 4500 and we now have a strong steady pull to to the next shift.
now the 2-3 shift comes up again at 6700rpm.Now the after shift rpm 5000 rpm,too high.so we drop the shift rpm back to 6000 for the 2-3 shift,4200,opps too low.so we go up to 6200.Right on 4500 and off to the next gear.

Now if the Marauder engine is blessed with a twin HP and torque peak and it does make power to 6700rpm then the torque converter will be worth much more than just the higher stall off the line....

[LincMercLover]

And the only way to find this out is to have the motor dynoed by itself, or in a car with a manual tranny.

[SergntMac]

Originally posted by rurumon
What about that link that posted a peak torque at 6200 rpms?

Is this BS? This is definately a reputable site, and it clearly pointed out that there was power higher up.

Ummm...I followed your links, but I cannot find any support for your statement that these dyno reports show power after 6200 RPM. None of them do. Max power is reached in the high 5000 RPM range, that is visible in the graph and readabkle in the figures that follow. The dyno report on the front page, as well as the two reports available at the links clearly show HP leveling out before 6000 PRM, and torque declining shortly thereafter.

Odd how the "bone stock" Mach 1 netted 270 RWHP and 286 RWTQ, and the slightly modded Mach 1, with K&N filter and Flowmasters netted 265 RWHP and 280 RWTQ.

I'm sure K&N and Flowmaster fans are pleased to see this posted on the 'net.

[cyclone03]

mac,and others,
follow the link to the dyno pages then search for marauder.
You'll kind a bone stock marauder that makes power to 6600rpm.

[nomad]

Go here for the 2 Marauder dyno tests:
http://dynoperformance.com/search_results.php?Model=marau der&Make=*&Year=*&Submit=Search

[TripleTransAm]

Winding out the 1-2 upshift to 6000+ RPM definitely hurt my times on the 1/4. I got my best results making her bark the tires at 5800 or so.

I could feel the car running out of steam at 6000 RPM.

[Zack]

About 13 Marauders and I will have precise answers for everyone Sunday night. Until then.....

[cyclone03]

Originally posted by TripleTransAm
Winding out the 1-2 upshift to 6000+ RPM definitely hurt my times on the 1/4. I got my best results making her bark the tires at 5800 or so.

I could feel the car running out of steam at 6000 RPM.

True,But...
If the rev limit is raised and the fuel and timing are adjusted correctly there may be power to be had above the factory limit.

My thinking on this goes back to the MACH 1,the cams,heads pistons and rods are the same as our automatic Marauders but the Mach stick cars get 7200rpm rev limits,I'm sure theres some power up there someplace....:D

But I wouildn't go looking for it with a stock converter;)

[TripleTransAm]

Originally posted by cyclone03
True,But...
If the rev limit is raised and the fuel and timing are adjusted correctly there may be power to be had above the factory limit.

Ahhh. Gotcha... but then we're talking a modified MM engine! All bets are off! ;)

[cyclone03]

Originally posted by JLHARVEY1
Also, I have a good understanding of torque converter stall speeds, but beyond that speed is an aftermarket torque converter beneficial? Is it more efficient at transferring the power to the axle. Or is the higher stall speed the only real benefit of an aftermarket torque converter?

yes.
The PI (precision Industries) converter also has a higher multiplication factor over the stock converter 2:1 over,I think 1.75:1 for the stocker. There's more to it than that,follow the links on Dennis' site theres a great article on transmissions and torque converters.

[notacop]

lets not forget that the stick mach 1 got the cobra crankshaft. this may be another reason it can rev to 7000 rpm. i don't believe we have this crankshaft.

[MarauderBoy]

What's the intake on a Mach 1 look like? Is it similar to an MM?

[Zack]

I go to the local Ford dealer to do visual comparisons all the time. If you pull up to a ford dealeship in a Marauder, they always seem to roll out the red carpet for us unique folk!!