How many 400 RWHP or better automatics out there

kenewagner

Registered User
Like the title saids. I gave it some thought and I know of some manual equip cars out there over the magical 400 RWHP with a V6 engine, but know of only one automatic
(David Neibert). Who else is running these kind of numbers sporting a automatic transmission in their V6 Thunderbird?

Ken
 
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Me but not in an sc,rather an 87TC with a supercharged 5.0L and an AOD.
Mine has a convertor and a valve bady though,handles it pretty well but i don't do brake stands or beat the crap out of it.
The 5.0L puts out around 500hp ,so none the less i'm surprised the aod has survived for 3yrs.
 
Me but not in an sc,rather an 87TC with a supercharged 5.0L and an AOD.
Mine has a convertor and a valve bady though,handles it pretty well but i don't do brake stands or beat the crap out of it.
The 5.0L puts out around 500hp ,so none the less i'm surprised the aod has survived for 3yrs.

I should have been clearer. Over 400 on a V6 engine in a thunderbird.

Ken
 
Ok Let me rephrase this

400 RWHP with a V6 supercharged SC Thunderbird equipped with an automatic transmission. No nitrous

There doesnt seem to be many that break the 400 mark equipped with an auto. From the replies it looks like
David Neibert
Payton
Maybe Kevin?
Rich?

Two for sure and maybe 4. One being a race car. Anymore?
My goal is to hit 400 RWHP and that is a lofty goal with a automatic and nonlocking TQ. Some feel it might be to lofty an expectation:rolleyes:

ken
 
Ok Let me rephrase this

400 RWHP with a V6 supercharged SC Thunderbird equipped with an automatic transmission. No nitrous

There doesnt seem to be many that break the 400 mark equipped with an auto. From the replies it looks like
David Neibert
Payton
Maybe Kevin?
Rich?

Two for sure and maybe 4. One being a race car. Anymore?
My goal is to hit 400 RWHP and that is a lofty goal with a automatic and nonlocking TQ. Some feel it might be to lofty an expectation:rolleyes:

ken

Ken,

Clearly it is doable...I just think your going to need better heads, exhaust and maybe a bigger cam. Figure your gonna need to make 10% more power at the crank than a 5 speed car to get the same numbers at the wheels, and your gonna be real close.

400/.85= 470.5 at the crank for 15% drive train loss (average 5 speed)
400/.80= 500.0 at the crank for 20% drive train loss (average auto w/lock)
400/.75= 533.3 at the crank for 25% drive train loss (average auto non/lock)

David

PS: If you add what the blower and accesories consume to calculate what the motor needs to make internally (and what you have to provide fuel and air for).....add at least another 125 HP. That being the case, your little 3.8 needs to be making around 650 internally to get 400 to the ground. If that doesn't blow your mind, do the math on what it takes internally to reach my 450 rwhp goal through the same tranny.
 
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I am not sure. But is it really a straight percent ratio? I mean I know its a good tool to use but when you get to 1000hp the losses start to get pretty ridiculous. So is it as clean cut as dividing the percent?

Also. I thinks Ken motivation although he want to get to 400RWHP is that he now has a twinscrew blower on the car and on other cars it has netted a very big advantage over the roots. But Kens Delta or magin between a roots and a twinscrew is not a big one.

Anything will make more HP with heads and cam and this and that, tune ect. But why is his car not responding to the hardware like expected.
 
Mine went from 425 with an 5-speed to 375 on a raced prepped fully rollerized C4, but the car the is 1/2 second quicker with the auto.
 
:D
Also. I thinks Ken motivation although he want to get to 400RWHP is that he now has a twinscrew blower on the car and on other cars it has netted a very big advantage over the roots. But Kens Delta or magin between a roots and a twinscrew is not a big one.

Anything will make more HP with heads and cam and this and that, tune ect. But why is his car not responding to the hardware like expected.

I have never made the HP I expected with the car. I have improved a lot of things and I did expect a much larger improvement going to a twin screw. I can only see one area that is weak and has not been updated and that is the headers which Dave said from the beginning sucked. The cam while small has produced good numbers for Dave. The heads while very mildly ported have larger valves and according to the numbers flow about 30% better than stock. The rest of the exhaust is huge. My TB plenum, I can insure you is bigger than anything else on a 3.8. I am running a 76MAF & 75 MM TB but having talked to guys like David Neibert they say HP increase were not that much going to a larger intake system. The lower intake and plenum is larger than stock by a lot even though it is likely not as big a performance mod as some thought. My IC is a front mount and has done well keeping the temps down acording to the dyno runs. I have the snow system and on and on. The new engine should have better flowing heads, havent got the numbers yet, a much larger cam, buillit proof bottom end, better valve train and on and on. The goal of 400 should be a realistic goal but than the car fights me all the way on it. My other goal is an 11 second quarter mile. 11.99 would be just fine with me. Than maybe I can get to the interior and change out my old carpet:D

Ken
 
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I am not sure. But is it really a straight percent ratio? I mean I know its a good tool to use but when you get to 1000hp the losses start to get pretty ridiculous. So is it as clean cut as dividing the percent?

Also. I thinks Ken motivation although he want to get to 400RWHP is that he now has a twinscrew blower on the car and on other cars it has netted a very big advantage over the roots. But Kens Delta or magin between a roots and a twinscrew is not a big one.

Anything will make more HP with heads and cam and this and that, tune ect. But why is his car not responding to the hardware like expected.

Ricardo,

I don't really think it's a straight percentage either, but for the power level we are at I think it's pretty darn close. Just look at Brian's numbers against the same drive train loss percentages I posted above.

425/.85= 500 crank (5 speed) 15% loss
375/.75= 500 crank (non lock auto) 25% loss


David
 
Mine went from 425 with an 5-speed to 375 on a raced prepped fully rollerized C4, but the car the is 1/2 second quicker with the auto.

I would suspect if you added an AOD to that the drive line loss would be even more so then the C4. Especially if it is a non-locker. :eek:
 
I think my car is probably close to the 400 mark or at least can be especially since we are only pushing about 17psi with the AR.
 
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