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Engine & DrivetrainDiscussions about the engine and drivetrain of your vehicle.
This is a discussion thread titled "no BS I need some more torque", within the Engine & Drivetrain forum, part of the Technical & Vehicle Assistance Forums category.
We just dragged home our new 23 foot Chaparral deck boat and my 2002 4x4 access is not all that happy about towing it. We live in Colorado and drive some big hills to go boating, plus the power loss to altitude.
What is the bottom line about getting a few more foot pounds out of the 4.7 at a reasonable cost? No supercharge in my future as the boat is already more than I should be spending. Am I gonna have to go with an American truck? Argggg!
No BS? You're not going to get any real significant power gains without some kind of forced induction = supercharger. Your Tundra was pretty much designed to produce the amount of torque it does (DOHC engines are traditionally not high-torque engines) the way it is built from the factory.
Quote:
No supercharge in my future as the boat is already more than I should be spending. Am I gonna have to go with an American truck? Argggg!
I've got news for you. If you can't afford a $4000 supercharger, how do you expect to afford an F250? Or any of the American trucks with a big block/diesel high torque engine? Its certainly going to be a lot more expensive than what you paid for your truck - even with the added price of the s/c - anything around the same price of the Tundra is going to have less torque and a weaker engine - unless you get something used.
Buddy of mine did a spacer on the intake runner and oversized the exaust to 3.25" with hiflow muffs... said it was 15% improvement from Stock ... Also added airbags to rear for leveling !
Good luck
Quote:
Originally posted by indecline How much does the boat weigh?
No BS? You're not going to get any real significant power gains without some kind of forced induction = supercharger. Your Tundra was pretty much designed to produce the amount of torque it does (DOHC engines are traditionally not high-torque engines) the way it is built from the factory.
I've got news for you. If you can't afford a $4000 supercharger, how do you expect to afford an F250? Or any of the American trucks with a big block/diesel high torque engine? Its certainly going to be a lot more expensive than what you paid for your truck - even with the added price of the s/c - anything around the same price of the Tundra is going to have less torque and a weaker engine - unless you get something used.
Originally posted by Johnnyrcp Buddy of mine did a spacer on the intake runner and oversized the exaust to 3.25" with hiflow muffs... said it was 15% improvement from Stock ... Also added airbags to rear for leveling !
Good luck
It may be an "advertised" 15 % increase but I can assure you that the setup described above will help your top end but your low end will suffer and that is where you need torque for towing. That exhaust system would need an x-pipe or similiar in order to help the low end. About the spacer are you talking about a throttle body spacer or did your friend make a custom spacer for the runner plenum?
Without going to a S/C the only other options maybe tuned headers and possibly some porting and polishing of the intake runners but neither of these will make a substantail difference. You can bet though as said already than any other truck in this class isn't going to make any better power than the tundra. If you're going to spend the cash get a S/C.
If a 1/2 Ton with more torque would be heavy enough, you might think about some options on an F-150 with a 5.4. They've got a lot more low end torque than a Tundra. You used to be able to get them with 4.10's. That would help too. The price should be about the same as a Tundra, maybe a bit less.
__________________ ADDING POWER HAS NEVER BEEN SO FAST!
A change in axle ratio is a permanent increase in torque applied to the ground - for a given ground speed - which is what towing needs. Maybe 15% higher gearing is what you need. Yes, in a 4x4 truck this requires two sets of gears to be changed, but that is the cost of 4 wheel drive.
Can you accept a 15% decrease in miles per gallon, to go along with the re-gearing? Re-gearing in this case is to make use of the higher torque the engine makes in the "higher than stock" cruising rpm (compared to stock gearing).
The Tundra V-8 has a torque peak at somewhere between 3,000 and 4,000 RPM. Until you chassis dyno your truck, you won't know the peak torque RPM (and equivalent ground speed for each transmission gear) for your truck. Re-gearing the axle ratios based on the dyno results should work well, if your wallet can handle it.
A change in axle ratio is the only thing that will work for you with this present truck.
Forget all the talk about torque. It's not meaningful. What you and everybody needs is horsepower at the rpms they're working the engine. Lower gear ratios make the engine spin faster and produce more hp at the same mph, at the expense of fuel consumption. The horsepower curve is what you need to consider. Any add-ons, K&N stuff, etc., need to be carefully evaluated to see if they give you any more hp at the rpms you really use, not more hp (if any) at peak rpm. If S&S ever gets going on the headers, they've been requested to increase the hp in the 2000-4000 rpm range, not at peak.
Right now, what can you do?
1) Never tow that boat in Overdrive.
2) Install an additional transmission cooler and synthetic ATF.
3) Run up to, say, 4500 rpm by manual downshifting...minimize shifts to minimize transmission heat and wear.
4) Downshift early when driving down hill, and come down in 2nd, or 1st if need be.
5) Your boat trailer has brakes, yes? Trailer brakes are essential anytime the total weight is above the truck's GVWR of 6k#.
6) Take your time.
7) Regear the differentials.
If you won't consider supercharger but think a new American truck is the answer than how much do you think that would cost you to get a new truck in comparison to the supercharger?
__________________
stock exhaust
Formerly Modified JBA headers now SSautochrome headers temporarily
TRD LSD
Extang lift off tonneau
Hankook DynaPro AS RH03
stock air filter & box
220 HP @ 4800 RPM
302 TQ @ 3400 RPM Run With Spintech Sportsman XL muffler, stock air filter, and JBA headers
208 HP @ 4800 RPM
285 TQ @ 3400 RPM Run With Spintech Sportsman XL muffler, TRD air filter, and stock manifolds
204 HP @ 4800 RPM
271 TQ @ 3400 RPM Bone stock
Quarter mile 15.526 @ 87.17 mph bone stock in 40-degree weather 2WD SR5 V8.
Quarter mile 15.389 @ 88.66 mph modified in 60-degree weather 2WD SR5 V8.
0-60 IN 6.88 seconds on G-tech
Dyno run results click here
If you won't consider supercharger but think a new American truck is the answer than how much do you think that would cost you to get a new truck in comparison to the supercharger?
Good point, except I would hit the rather soft market of full size sport Utes. They are giving away Tahoe's in Texas. Friend just bought one on ebay, $9,200 for a 98 with 80k miles loaded. Perfect and loaded too.
On the other hand, I just compared a Tahoe (98) and my truck pulling my boat (4k pounds plus big ol' trailer and 50 gallons of fuel) and there was almost no difference except on the extreme bottom end.
I did your pulse mod and it really did feel like it pulled better from a stand still. I am thinking the spintech is for me, as well as perhaps a set of headers. Anyone try the JBA's from this site? AEM said they will an intake kit by end of the month, and they post dyno numbers, just like v8toilet!!
no BS I need some more torque
Our tundra's can't pull that, it's too heavy for a toyota.