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02:47:47 - 12/29/2024
Dakota Performance
From | Message |
Cotharyus GenI
8/07/2002 16:21:58
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Subject: Hard facts on 4.7 upgrades? IP: Logged
Message: Pardon the length on this one, but there are some things that need to be straightened out.
First I'd like to thank Yates, CW, and Dunner, among others for thier help so far in boggling my mind to the point that it is. Let me get to the point.
I don't drive my truck or upgrade it for speed. Don't get me wrong, speed is good, speed is fun. But first and formost my truck is for work. That means a lot of low RPM grunt work, from pulling trailers to dragging logs. So far, I've found the truck capable of doing everything that I've asked it to, but there are a few hills I'd still rather not have to down shift to third gear on. That being said, examine the current situation:
I was traveling between to points today, via a route that I have known existed, but never been on before. I popped over the top of a hill on this basicly deserted road, to see nearly 2 miles of straight away in front of me. Grinning from ear to ear, for the first time in the 3 months I've had the truck, I eased the peddle to the floor in 5th gear, and down the road I went. Things were shaping up nicely until I hit about 85 MPH, and the truck seemed to back off a little. It didn't quit pulling, it just quit pulling as hard. Now, I wasn't looking at the tach at this point, but I assume it was showing somewhere around 3000. Should this truck back off there, or should it just be getting into its groove? I haven't done anything to the exhaust - in fact all I've done so far is the intake. But I have to wonder what caused it to draw up so sharply there.
My quandry is this: I have heard good things and bad things about exhaust mods on this engine. I've heard it really helps the top end. I've also heard it really hurts the low end. I'm looking for recommendations based on facts, not "it feels like". I don't care what the truck sounds like, however I would like to be able to hear myself think when I'm going 70. I've also considered the HO cam and intake - I know CW said that the intake really helped his truck keep pulling in the upper RPMs. I haven't ruled out a computer flash, but when a company can do as much as KB with info on cams and such, I'm thinking I'm going to hold off on that until I get all the major stuff out of the way. Can anyone comment on how to get past this? 4th gear is always an option, but eventually that's going to tap the rpm limiter (if it doesn't tap the speed limiter first) and who wants to drive around in 4th all the time anyhow? Thanks for an insights.
2001 QC 4x4, 4.7,5 spd, LSD, K&N Gen II Intake
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yates-in-DE GenIII
8/07/2002 17:18:55
| RE: Hard facts on 4.7 upgrades? IP: Logged
Message: Will it run in 5th gear that slow? I thought that 5th was for 95+ mph. HUH, I'll go out and try it that way right now. :)
Later,
My VW Killer Lynn
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tony597fitter Dodge Dakota JOIN HERE
8/07/2002 17:35:16
| RE: Hard facts on 4.7 upgrades? IP: Logged
Message: mbrp says you loss no low end torque and gain a few horses. Mine should be coming this week. Check them out www.mbrp.com. Most exhaust are 3" single or 2 1/2" duals, Mbrps dual are 2 1/4" so you dont lose any low end.
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Cotharyus GenI
8/07/2002 18:13:33
| RE: Hard facts on 4.7 upgrades? IP: Logged
Message: Yates - I geuss I'll have to post a picture like your cruising speed one of me going through town idling along at 40 MPH in 5th gear...
Tony597fitter - what sort of cost are you looking at for what system from MBRP - their site appears to be very new and still under construction.
2001 QC 4x4, 4.7,5 spd, LSD, K&N Gen II Intake
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CasuObserver Dodge Dakota JOIN HERE
8/07/2002 18:44:31
| RE: Hard facts on 4.7 upgrades? IP: Logged
Message: Does the torque go soft at 3000 rpm in other gears, too?
If not, then I'd wager it's not a pure engine problem (unless too much air is being forced into the intake due to vehicle speed, which is not likely).
I'd guess then that is might be a programming problem/feature, that takes into account vehicle speed as one of the inputs. For some reason torque backs off at this rpm and speed. Weird changes to ignition timing or fuel delivery are the only things that can be modified at this point, right?
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CW GenIII
8/07/2002 19:23:34
| RE: Hard facts on 4.7 upgrades? IP: Logged
Message: No sure what to say to that as most of what I have done is to push the engine into the higher RPMs. I think the cams would help for sure. Good torque mod. Not what I was looking for at the time but helped on top some as well.
2001 4.7HO RC 5sp 3.92 LSD Click on thumbnail for mods
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j Dodge Dakota JOIN HERE
8/08/2002 00:43:51
| RE: Hard facts on 4.7 upgrades? IP: Logged
Message: I know it's expensive, but if you are looking for torque, the KB s/c worked great for me. I have an automatic though. The boost kicks in not with rpm, but with throttle position, so you're always in control. It's like a completely different engine now.
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