It will take 100HP to turn a 106mph car into a 115mph car, all else being equal. The test cannot possibly be correct.

 

These numbers don't make sense.

 

So which one is it? This engine is underrated or the last engine was ovverated?

 

Or both or neither? Or maybe the 4.3 simply wasn't tested well. The initial R&T test got a 0-60 of 4.7 and a 1/4 of 13.1 @ 107.9. Other test cars didnt fare as well, but at least one of them was a not supplied by AM and was on HREs. Hard to say, but my car sure feels faster than a mid-high 13 second car.

That said, I tried a few horsepower calculators but they seem pretty useless and are all over the place. They are very crude calculators which only take into account a few variables, and leave out a ton of others. I tried using them for some other comparison cars and the numbers were way off for those, too. So...there's really no telling.

 

No one ever got close to that initial MT test as far as numbers though. But still there is still a huge difference between 107 and 115 mph traps speeds, and its more than 40 hp. Maybe it is the power under the peaks that is making up for the difference?

 

Couple more comments to add:

1) Watch the press for the 2010 Jag (I think it will be out) w/ a little over 500 HP (510?). This supercharged "R" version will be in the coupe and sedan - and most likely under $100k. Suppose to revise suspension too. Ford is no longer saying they do not want it faster than the AM. If it goes as fast as the are saying it will be hard to tell if it is a Jag or AM ! (ouch - Dr Bez are you reading this!) AND the designer went w/ Jag in the company sale - so expect the upgrades to look good too.

2) With my 4.3 and mods (Power Pack, 200 cell cats, Quicksilver Exhaust, K&N filters, Open Airboxes, H&R springs, Brake cooling kit) the power band does not drop off at the higher revs - feels faster mid thru high. I have driven a 4.7 w/ handling option and it seemed much more than just 40 HP - I am trying to say suspension, trans & eng made a very nice combo vs. stock 4.3.

I really need to run against a 4.7 and see how my car does in a straight line and twisties ...

 

I want to see dyno graphs between the two cars it would tell me more. My questions is 420 hp is peak hp but there has got to be more than a few points that this car is making closer to 60 or 70 more hp.

 

Mike,

Have you had you car dynoed or tested the 0-60? I have to believe that you're close to 4.7 performance. Do think that you'll get the ECU flashed and have you contacted a company maybe in the US to do this?

 

I would love to see the modded results of a 4.3 against a 4.7. I am thinkin of doing the dealer supplied upgrade, but want to know what I really get for my money.

 

jaymoney - no I have not dynoed my car. Also I should have done a "before" dyno so we could really get an idea of the difference on the same test bed. Yes there is a difference but I do not have a very good "dyno butt" meter to give figures.
There is a software change with the AM Power Pack - that is part of the 20 HP increase. Just what is done to the ECU is a bit of a question. I do not think they give the dealers a fully detailed explanation other than - here is the new SW, please load after installing the Hardware.
Yes I think I am close or a litttle more than the 4.7 420 HP. I do think you can get there w/ a 4.3 by changing exhaust, filters and some SW (AM or other) - AM left some HP on the table w/ the 4.3, their Power Pack helps.
The 4.7 is a very nice overall change, I think the question is whether you already own a car, buying used, or looking at a new car - what do you want to spend. The 4.7 is a bit more than just buying 40 HP - IMHO.

 

I hope that someone comes with a reliable supercharger package for 4.3, give us 100HP and a reasonable flat torque for say around $10K and we call it a day.

 

Make your own, heck you can even turbo it. Make sure your boost management and tune is dead on and run no more than 4.5 psi non intercooled or possible 7 psi intercooled with meth injection.

 

I'm running 6.5 psi with water-air intercooler and have no issues with the car. I believe it could handle over the 510 RWHP I have. Combined with all the kits out there, there has been 15K to 20K trouble free supercharged miles.

 

I know I've asked before, but have you had a chance to test your 0-60 time again?

 

Does the stock clutch and transmission handle the added HP (say around 100) by the supercharger comfortably?
Sorry if I'm asking too many questions,..I'm new to Vantage