168 HP "Built" 401???

[1980_Cj7]

Just got done reading the new 4WHEEL & OFF-ROAD. There's an interesting (especially since we are getting to do the same thing) article in it about putting a Howell TBI on a 401 in an 79 Cherokee Chief.

They state it was a "built" 401, and they dyno'd it before, with the carb, and after, with the TBI. With the carb it produced 168.47 HP/238.81 ft. lbs. Talk about disappointing! With the TBI, it did 181.30/258.89. At least it was an improvement! (I had heard or read that we might experience a loss of power with the TBI, although better starts, response, mileage, and off-camber performance.)

The Jeep belongs to Jeeps R Us, and they didn't elaborate on what "built" meant, but those are some really disappointing numbers. Now I know I don't want to put ours on a dyno, especially after the amount of money we just poured into the engine having to do 2 complete rebuilds in just 300 miles!

Anybody else see this article and have any comments?

[jeepsr4ever]

Was that at the wheels?

[1980_Cj7]

I wondered the same thing, and looked thru article several times, but couldn't find anything that said whether it was at the flywheel or rear wheels. I certainly hope it was rear wheels.

[mike4089]

pretty sure that was at the wheels and that jeep had some great big tires on it also

[tufcj]

I'm sure the numbers were at the rear wheels, since they were using a chassis dyno. 35" tires would have affected numbers, depending on gearing, but I agree that 168 is very low. Even figuring about 75HP for loss in the drivetrain, it's still below 250 at the crank.

I have a Howell on my 360. I had a Holley that was tuned using a gas analyzer on it prior, so the carb was spot on. With the Howell, I saw no change in mileage and no "seat of the pants" change in performance. The easier start, smoother idle, crisper throttle, and running at any angle were more than worth the price on my rock crawler.

Bob
tufcj

[Goose]

I think this is another case of perception / deception.. with an auto tranny, 35" tires.. maybe gear a skosh too tall.. all those things eat a lot of hp..(even more than the 75 hp you guys were talking about) plus depending on how you dyno it.. If you look at the typical hp/tq curves the hp numbers dont start to build until up higher.. with 35" tires etc.. they may not have gotten that high.. I agree thier numbers are really disaapointing sounding.. as 250 crank hp is about a semi stock 304.. but those torque numbers through all the losses are not bad..
But I am sure there must be more to the story than that.. I would consider "built" to mean at least 1hp per cubic inch (considering many factory stock modern engines can achieve that) though I think we get convinced that there are a lot more 500 hp engines out there than have ever existed in captivity.