SC400 to be faster then 400hp Vette?

[hnknrob]

firstly id like to thank you for not thinking im being a **** for disagreeing with you, as that definitely wasnt my intention. like i said i was just speaking from my experience.

but i do think its a big stretch to say that efi in north america is in its infancy. seeing as how many 7 second street cars are competing at this point in time. among the fastest of which is a mustang that ran 7.50's on 28x 10.5's, which isnt a big tyre by any means.

my biggest reference to north american and australian straight line acceleration going in different directions, was with australians seeming to use alot of roots or twin screw type blowers, where in north america pretty much everybody goes with centrifugal blowers or turbochargers. and most of those here that are using twin screw or roots blowers in really high horsepower cars are associations where the rules state they have to to maintain a level playing field.

 

[Anaema]

ya, the american car companies still havent started to use DGI either.

 

[jibby]

A few more questions if you guys don't mind -- Does anyone know if there is a difference between the stock Sc400 Tranny and Supra tt auto tranny and their hp handling capacities? I have not looked into the compatability and simularities to one another. I should have probably done a search on this... My thinking is swap that Supra tt auto tranny into the SC400 if it is a better transmission. Anyone?

In regards to all this turbo and supercharger talk, isn't there one thing we haven't discussed which is which setups have proven to produce more HP in general when going all out? A massive single or twin turbo or a monster Super Charger/blower? I believe the answer is Super Charging on average if I am not mistaken. Also from what I am reading belt slippage seems to be the most common problem with supercharging.. I am sure that problem can be addressed with some work and altering, no? Just look how the timing belts grip in comparision to the serp belts.

In conclusion I have just printed out this entire thread, and using it as a learning tool to research and boost up my automotive IQ, which is lacking greatly in comparison to you folks. Time to read up and get greasy!!!!

 

[Philly#1 Lex]

A few more questions if you guys don't mind -- Does anyone know if there is a difference between the stock Sc400 Tranny and Supra tt auto tranny and their hp handling capacities? I have not looked into the compatability and simularities to one another. I should have probably done a search on this... My thinking is swap that Supra tt auto tranny into the SC400 if it is a better transmission. Anyone?

In regards to all this turbo and supercharger talk, isn't there one thing we haven't discussed which is which setups have proven to produce more HP in general when going all out? A massive single or twin turbo or a monster Super Charger/blower? I believe the answer is Super Charging on average if I am not mistaken. Also from what I am reading belt slippage seems to be the most common problem with supercharging.. I am sure that problem can be addressed with some work and altering, no? Just look how the timing belts grip in comparision to the serp belts.

In conclusion I have just printed out this entire thread, and using it as a learning tool to research and boost up my automotive IQ, which is lacking greatly in comparison to you folks. Time to read up and get greasy!!!!

Um I think you are inaccurate with the supercharger putting up more power than the turbo 1UZ's. Excuse me if I am wrong but rdm20fan is putting down 510whp on 18psi and the stock slushbox. I dont see any of the chargers coming close?

 

[hnknrob]

In regards to all this turbo and supercharger talk, isn't there one thing we haven't discussed which is which setups have proven to produce more HP in general when going all out?

at the end of the day everyone has their own perferences. but i will say this, the only places in all out racing where superchargers are really used anymore is in the nhra or the ihra. and thats because both associations banned turbochargers out of competition because they gave their users an unfair advantage over the roots style blower boys. even now in some of the outlaw classes where they allow both turbochargers and superchargers, theyre limiting the size of the compressors because they found the belt driven boys simply couldnt keep up. the only knock against turbochargers is the lag associated with them. but if yorue drag racing youre pre-loading the turbo and leaving well into the boost anyways, and in the case of top end driving, youre again going to be away from the area where your turbo will suffer lag. something else to consider that was mentioned earlier, the advent of new turbocharger technology combined with proper sizing should eliminate any unneccesary lag.

 

[Pro]

but i do think its a big stretch to say that efi in north america is in its infancy. seeing as how many 7 second street cars are competing at this point in time. among the fastest of which is a mustang that ran 7.50's on 28x 10.5's, which isnt a big tyre by any means.

my biggest reference to north american and australian straight line acceleration going in different directions, was with australians seeming to use alot of roots or twin screw type blowers, where in north america pretty much everybody goes with centrifugal blowers or turbochargers. and most of those here that are using twin screw or roots blowers in really high horsepower cars are associations where the rules state they have to to maintain a level playing field.

you can disagree all you want dude! we all have differing opinions.

turbos are the "norm" here in OZ along with paxton/vortech style superchargers, it's just it "seems" that we're along the M90 / MP112 route because a few people on this forum made kits for these type of blower to suit the 1UZFE because they're for racing boats - and if a kit is available then chances are the R+D is done and therefore it's a more attractive option.

i would hazard a guess at saying that if someone were to FI a 1UZFE, it would be about 60/40 in a turbo's favour. of the remaining 40%, half would be a centrifugal style blower and the other half a more traditional rootes / screw.

 

[rdm20fan]

Does anyone know if there is a difference between the stock Sc400 Tranny and Supra tt auto tranny and their hp handling capacities?

Basically they are the same. there is no difference in torque capasity.
The early SC's use a cable to adjust the fluid pressure, and the supra's do not. but the supra guys claim trans failure at 350hp.
Mine was living at 320 hp, and lasted a week at the 370hp mark. (All rear wheel)
The clutch material, # of clutches, line pressure are the same.

 

[hnknrob]

rdm20fan : any idea if the trannys of the sc400 and the tt supra use the same case or not? i ask just because im wondering what the difference between the 2 trannys is, i imagine its just the gear ratios, but i thought id ask someone more knowledgable.

pro240c : your point about the existing 1uz s/c kit is well taken :veryhappy

 

[rdm20fan]

Yes they are the same. the SC300, 400, and supra use the same auto trans. they have different versions, so the gears ratios may be different, but basically they are the same trans

 

[jibby]

You guys are great and have answered all of my questions and then some...thanks.. The only reason I am suggesting the supercharger/blower has a better potential for massive hp and duration is that on all these big block Ford and Chevy's which are basically just larger V8 versions of the IUZ.. such as the 454 and 460ci etc... I have rarely if ever seen a turbo setup on these monster engines. It's always the blower/supercharger and the huge 4 digit horsepower that goes with it. On the reverse side all the smaller 4 and 6 cylinder motors are mostly running the turbo's. So as to what "Hnknrob" say's about the banning of turbo's in compition would make perfect sense...I just can't ever ever remember seeing a twin turbo big block in all my years of messing with American motors. I am sure there have been some but the norm is Supercharging/blowers here in the US.... Maybe I should look and learn more about Turbo charging....See ya...

 

[Pro]

google "eddy tassone" and see what comes up.

 

[jibby]

The Ford Dyno'd at 1311hp not too bad I would say. I could not see if that was turbo'd or supercharged. Anyway, a very powerful setup to say the least....I would fall over in my chair to get my car running with half that power!!!!!

 

[Spinall4]

true - we have the only 8.5 sec untubbed street car too (rotorworx KE20 corolla).

There's a guy over this side of the pond running 7.9 @ 179 untubbed, street car, 2650 lbs with driver, Hoosier DOT 26x8x6 tires, http://www.shepracing.com/index.html

Yes roots & twin screw blowers have always been touted as way to go for a street car, beacuse of there direct connection to the crank via belt. Turbos have come a long way, and with propperly sized ball bearing turbos, good exhaust manifolds, ceramic coating, thermal insulation, and propperly sized cams you can have a turbo setup that spools extremly fast. Hence the point for turbos with anti surge ports, these huge turbos are spooling so soon they're crossing there surge limit. The point is really moot, as all I see the SC400 doing with gobs of low low end torque is burning rubber.