highway rpm's with the gear change

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BigBadMerc

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Just wanted to know what rpm's you guys with the 4.10's are turning at highway speeds ie. 55- 60mph. I am going to have gears installed next month but was told 4.10's are too much that 3.73's were a better choice.
 
Welcome, BigBad....

I don't have the 4.10s yet, but I've heard it raises the RPM by about 325 or so...others will chime in, here.

I want to know about your Diablo Sport chip...how much $, how much improvement, etc...most of us have Dennis Reinhart chips...did you need to change the plugs and 'stat with the Diablo?
 
The Diablo was $255, I didn't have to change plugs or thermostat, just run high octane gas, but I did that already. Go to diablo's website and see the gains for yourself, on a rear wheel dyno it made a little better than 60hp gain, but if you look, the gain is in the bottom and mid not the top, top end looked more like 20 or so. and it also smoothed out the flat spot at around 4000rpm, and I was happy about that. It also made the shift points 500 rpm higher and fuel cutoff is at 7000rpm, and their is no more 117mph limiter either. Overall I am very happy with it. And you could tell the power improvement imediately without having to go to wide open throttle to notice.
 
The math is very simple. divide 4.10 by 3.55. That gives you 1.155. Multiply 1.155 times any present (3.55 Axle) rpm to get the new rpm with a 4.10 axle. This also means that for any given engine rpm, you will have about 15.5% more torque available at the rear wheels.
 
4:10 gear change

I put the 4:10 gears in last week and I'll tell you the drivability is fine, the midrange power band is much better and because we have 18 inch wheels it probably is equal to a 3:91 or something. I don't think the 3:73 gears will make you happy. I was hesitant to go 4:10 but the guys that have them all agree it helps the car quite a bit and does not take away from the cruising aspect. I highly recomend the gear change now that I have done it myself.
 
I posted some RPM stuff a while back, so have a few others. Maybe you could try a search from the home page?

IMHO, you were told wrong about the 4:10, but honestly, this is really a matter of your personal preferrences. You may be pleased with a 3:73, but others here have tried them, and moved up to 4:10 anyway. The 8.8 housing can take up to 4:33, and that is an option for those who prefer performance over overall drivability. However, the 4:10s seem to be the sweet spot between economy, and performance. I have not experienced any remarkable loss of MGP, and in some conditions, that has improved. Yes, moving up to 4:10 alone will have it's penalties, but they are not severe, average of 500-600 RPM over the 3:55, I believe. As part of a performance profile, (Reinhart chip, gears, stat and plugs), the program works really sweet. I won't speculate over how well the 4:10 benefits the Diablo chip, I don't know it's specs. IMHO.
 
Went to that www.motorhaven.com site and read all the notes. I believe the Diablo is someone's aftermarket name for the the same Delta chip Reinhart sells us. Same features, same results, same options. Not the same price, I paid Reinhart 325.00 for a two stage chip with on/off octane switch. Key lock and LED were options, and are plug-in add-ons down the road.

Knowing this, I'm comfortable in suggesting that you consider the 4:10s over the 3:55s.
 
BigBadMerc said:
The Diablo was $255, I didn't have to change plugs or thermostat, just run high octane gas,

Sorry, I just got it...I thought you already had a chip...Dennis's are about $325...
 
If it REALLY is a 60hp gain...then it's 3 times better at 60% of the cost. BUT....I don't know if the gain is true....

I'll stick with Dennis' chip unless proven otherwise...
 
yah...I think I paid like $370 something for the chip, plugs, and 'stat (inc. shipping)...the gears are something like $180 more...

As far as differences, I have no experience with any chips but Dennis's...BigBadMerc's answer said they claim 60 HP increase, but I find that a little hard to believe, especially with no change of plugs or thermostat...hell, if it makes THAT big a difference, who needs 4.10s?
I'd be willing to bet the Diablo Sport chip is no better than the DR chip in actual use...
 
Ah...may I add...please?

I visited a number of sites today, all offering a "something" Delta chip.

One has to be careful in reading the detail on these sites. It's not only what they tell you, but also what they do not say. One site boasted a large HP and TQ gain, but twisting through the detail tells us that the test vehicle was a diesel pick-up truck. Another cited likewise benefits, but promising better "towing" performance.

Sifting through that nonsense, the accurate report I could find is more consistent with what Reinhart has promised me. So, I conclude, for my own purposes, that the Delta Chip, under anyone's added banner, is what we get, and what works best in our MM application. I also conclude that Reinhart, is "on our side" in this.

I paid 325., got a chip with a switch and many possibilities. Yeah, maybe I paid a few dollar more than I could have, but I feel I've made my best investment too.

I got a connection to a guy who's driving his LM like he stole it. A guy who answers his phone when I call. A guy who tells me the straight dope on stuff, like drive shafts and torque converters, anything, as long as I don't ask stupid questions twice. A guy who is working on MMs everyday, and knows the car I'm living with. He knows enough to suggest more "fine tunes" with plugs and stat, and he's also a guy who promises a full money back guarantee if not satisfied, NQA, and handles warranty claims (on his chip) the same way. He says he's had only two come back, and he replaced both, for the cost of the shipping charge.

Yeah, I maybe spent more that I could have, but I did so out of trust and respect for a guy who's watching out for my back too. When I worked for Mr. Norm's GS Dodge, I took a lot of phone calls from guys who wanted to know the bottom line. I told them the truth, in a voice that sounds a lot like Dennis in my ear.

Like I've said about other mods here, cheaper isn't always better. Best isn't always better, in the long run. Boast needs to be defined, and absorbed accordingly. So, I gotta go with the guy who will be there when I need him, a guy who answers his phone.

People who "have been there and done that" rate high with me. Whether they are tuners, wrenches, cops, firemen, lawyers, or doctors, I want to talk with the guy who walked my beat before I do anything.

Y'all decide for yourselves, be safe.

SergntMac@aol.com for rebuts...



PS. Sorry for my rant, but my meds don't affect my honesty.
 
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