Ive always liked the twins setup. Single would be cheaper and is a good thought. Im so up in the air at the moment, im just teady for a change and going back whipple wouldnt make any sense.
Going Twin Turbo & Need Opinions
- Thread starter tarheeltrooper
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Ive always liked the twins setup. Single would be cheaper and is a good thought. Im so up in the air at the moment, im just teady for a change and going back whipple wouldnt make any sense.
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I get what you're saying Venomous, but I will say that about 99% of people with Sullivan's don't have the car geared properly or the setup correct.. The lack of low end from a Sullivan can easily be made up through gearing.
Take old school stuff for example. A big ass 408W setup.. 225CC or bigger heads, 780+ lift cam, huge carb, massive headers, 12:1 comp. etc etc.. All built for top end.. It's pretty much mandatory you run a 4.11 gear in the rear to get you to where you need to be..
I have yet to see on a forum or in person a properly setup combo utilizing a Sullivan. Most people stop a pull at 7k rpm. Which to them is "HIGH" rpm.. When really it isn't. You already know the importance of spinning RPM with a Short Runner setup like we've talked about many times. I would say that he'll be ok running the sullivan as long as he changes his gearing and doesn't mind turning RPM.. The 2nd issue as to why most 03/04 Cobra guys don't spin RPM is that the computer can't really handle it.. Not like how a 98 Cobra Computer can. So at that point it's not really worth it.. But even a street car with a Sullivan can be fun
.. I plan on it atleast ahahaha. :beer:Tarheel: do you plan on going with a aftermarket ECU by any chance?
Compound with a whipple!! Now that would be different!!!... Got rid of my classics so we won't be twins anymore and people will stop tagging you in pics of my car on Instagram lol!!!! Just wait till you see the new wheel set up!
Going Twin Turbo & Need Opinions
Youre right chris.
I guess i came on a lil too hard on the guy.
Sorry if i hurt your feelings tarheel.
Just trying to avoid another talking about how people didnt like theyre turbo setup,which is why you and i mentioned,mismatched setup.
Hell,i was going with the sullivan for my 5.4.
But as soon as i saw that i could adapt that CJ manifold....looks good.and goes well with my setup.
Goodluck with the build tarheel
I apologize.
I get what you're saying Venomous, but I will say that about 99% of people with Sullivan's don't have the car geared properly or the setup correct.. The lack of low end from a Sullivan can easily be made up through gearing.
Take old school stuff for example. A big ass 408W setup.. 225CC or bigger heads, 780+ lift cam, huge carb, massive headers, 12:1 comp. etc etc.. All built for top end.. It's pretty much mandatory you run a 4.11 gear in the rear to get you to where you need to be..
I have yet to see on a forum or in person a properly setup combo utilizing a Sullivan. Most people stop a pull at 7k rpm. Which to them is "HIGH" rpm.. When really it isn't. You already know the importance of spinning RPM with a Short Runner setup like we've talked about many times. I would say that he'll be ok running the sullivan as long as he changes his gearing and doesn't mind turning RPM.. The 2nd issue as to why most 03/04 Cobra guys don't spin RPM is that the computer can't really handle it.. Not like how a 98 Cobra Computer can. So at that point it's not really worth it.. But even a street car with a Sullivan can be fun
Tarheel: do you plan on going with a aftermarket ECU by any chance?
Youre right chris.
I guess i came on a lil too hard on the guy.
Sorry if i hurt your feelings tarheel.
Just trying to avoid another talking about how people didnt like theyre turbo setup,which is why you and i mentioned,mismatched setup.
Hell,i was going with the sullivan for my 5.4.
But as soon as i saw that i could adapt that CJ manifold....looks good.and goes well with my setup.
Goodluck with the build tarheel
I apologize.
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I mean you make sense, but there is a lot to factor in. A fun street car not racing etc etc, it would make sense to have a TS on there for the low end grunt.. To me at least. But it doesn't mean that TT's could be done effectively. It's going to take a lot of time, money and switching stuff around though .. But he loves the build portion. I personally hate it hahahaha.. Way to much money lol.
.. But he loves the build portion. I personally hate it hahahaha.. Way to much money lol.
I mean you make sense, but there is a lot to factor in. A fun street car not racing etc etc, it would make sense to have a TS on there for the low end grunt.. To me at least. But it doesn't mean that TT's could be done effectively. It's going to take a lot of time, money and switching stuff around though
Hahaha,thats exactly where i am now!
I hate this aswell,just want it to be done so i could drive the SOB.maybe thats why ive been so angry.... Lol
A Sullivan isn't needed unless you are planning to turn 8-8500 rpm if we are talking racing.
TC your car will be nice I look forward to seeing the finish product. Please pm me if you have any ? At all.
:beer:
Also raresnake I haven't forgot about you but just have been busy as me and my wife just had our first kid.
TC your car will be nice I look forward to seeing the finish product. Please pm me if you have any ? At all.
:beer:
Also raresnake I haven't forgot about you but just have been busy as me and my wife just had our first kid.
WOW the F1 is going away the car looks so perfect with that in there... best of luck with the turbo i'm sure it will look just as good when it's done..:beer:
best of luck with the turbo i'm sure it will look just as good when it's done..:beer:
Just out of pure curiosity not hating, can you high hp guys even feel the difference between 900 and 1000hp on the street?
Everyone is going turbo! Lmfao
Will there be any twinscrews left?
Can't wait to see how this project progresses TC! I'll be starting my own build thread soon ;-)
Will there be any twinscrews left?
Can't wait to see how this project progresses TC! I'll be starting my own build thread soon ;-)
It's been tried, the twin screws can't handle it and blow seals.
Compound cars have a lot of headaches with no real benefit quickness wise.
Great build up, good luck! Sullivan aren't always lag switch's. I made 750/700whp/tq with journal 57/48's .48a/r at 15psi on pump gas and a sulivan years back. Lag was not an issue, it was a t56 3.55 geared car. Everyone loved how torquey it was. The trick is a sulivan upper for looks and hpp lower for mid range. I had factory c heads, factory cams, etc. That combo made 870whp at 24psi, but was maxed out. It was gaining power to 6750rpms but had over 500wtq at 2800rpms.
If you stay at or near 4.6L displacement, running a t3 isn't a bad idea so long as you run 3" hotside. Back pressure will be boardering on high with twin 62mm t3's and .83 a/r's on a 4.6 even at 3" hotside. The main reasoning being the turbos will simply be at or near full song.
I read up and came to terms with this while building my current combo and chose to go t4's. I went 62/65's from comp with ceramic coating, triple ceramic ball bearing triplex units, oil/water cooled, blankets, etc etcetera. They've been great. We're using .70 divided a/r's to help spool, and went 5.3L cammer block (4.6 deck height) to better utilize that much air/optimize the combustion chambers. To keep a great low and mid flow, an fr500c intake (arguably ugly, but I had it coated nicely and it's unbeatable flow/performance from 1500-6500rpms, where I usually play) as well as fgt heads with custom cams all dialed around a 7200rpm redline. Even still I'm swapping in 3.73's but might try 3.55's after.
I mention that all for relatable context. T56, IRS/street/cruise car here as well. On your build, I'd say only go (.70 at most) t4's in a 62/66 precision as you'd mentioned if you will be running a 5.0-5.3l stroker/bb stroker combo. It's a great setup for minimizing back pressure and optimizing longevity of the turbos/minimizing heat, but it's simply too much turbo for a street/cruising 4.6 IMO with a sulivan, t56, and anything less than 3.90's+ in the rear. It won't be awful or anything but those turbos would better fit a 5.0-5.3 vs a 4.6 for street duty. Guys have made 1000whp on precision 58's with 4.6's and 5.0's as a reference scale so 1000whp is an easy goal. Boost controllers allow you to go from 5-30psi as easy as changing radio stations. I recommend a truboost but everyone has their own preference. Always know the safe zones, don't run high boost on pump gas, your tuner can explain it all. It's easy stuff.
If you run a 5.0-5.3 with t4 62/65's, I'd say start with a 3.73 and see if that's working, if not step up a bit to a 3.90 or 4.10. With the sulivan, it might need a just a bit more gear. I ended up choosing an fr500c intake and fgt heads because my time is spent mainly under 7000rpms and my built t56 won't shift "well" over 7300rpms. Keep in mind the tranny will likely need some work to properly support the build. I'd recommend a McLeod clutch as well, and a lightened steel wheel (a few lbs more vs aluminum but it helps turbo cars spool).
If you stay at or near 4.6L displacement, running a t3 isn't a bad idea so long as you run 3" hotside. Back pressure will be boardering on high with twin 62mm t3's and .83 a/r's on a 4.6 even at 3" hotside. The main reasoning being the turbos will simply be at or near full song.
I read up and came to terms with this while building my current combo and chose to go t4's. I went 62/65's from comp with ceramic coating, triple ceramic ball bearing triplex units, oil/water cooled, blankets, etc etcetera. They've been great. We're using .70 divided a/r's to help spool, and went 5.3L cammer block (4.6 deck height) to better utilize that much air/optimize the combustion chambers. To keep a great low and mid flow, an fr500c intake (arguably ugly, but I had it coated nicely and it's unbeatable flow/performance from 1500-6500rpms, where I usually play) as well as fgt heads with custom cams all dialed around a 7200rpm redline. Even still I'm swapping in 3.73's but might try 3.55's after.
I mention that all for relatable context. T56, IRS/street/cruise car here as well. On your build, I'd say only go (.70 at most) t4's in a 62/66 precision as you'd mentioned if you will be running a 5.0-5.3l stroker/bb stroker combo. It's a great setup for minimizing back pressure and optimizing longevity of the turbos/minimizing heat, but it's simply too much turbo for a street/cruising 4.6 IMO with a sulivan, t56, and anything less than 3.90's+ in the rear. It won't be awful or anything but those turbos would better fit a 5.0-5.3 vs a 4.6 for street duty. Guys have made 1000whp on precision 58's with 4.6's and 5.0's as a reference scale so 1000whp is an easy goal. Boost controllers allow you to go from 5-30psi as easy as changing radio stations. I recommend a truboost but everyone has their own preference. Always know the safe zones, don't run high boost on pump gas, your tuner can explain it all. It's easy stuff.
If you run a 5.0-5.3 with t4 62/65's, I'd say start with a 3.73 and see if that's working, if not step up a bit to a 3.90 or 4.10. With the sulivan, it might need a just a bit more gear. I ended up choosing an fr500c intake and fgt heads because my time is spent mainly under 7000rpms and my built t56 won't shift "well" over 7300rpms. Keep in mind the tranny will likely need some work to properly support the build. I'd recommend a McLeod clutch as well, and a lightened steel wheel (a few lbs more vs aluminum but it helps turbo cars spool).
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HPP makes a lower intake?
Going Twin Turbo & Need Opinions
Sure you can.
Now if you ask how much you feel depends on how much torque youve gained
I dont know about the street though,usually that power is useless on the street.
Sure you can.
Now if you ask how much you feel depends on how much torque youve gained
I dont know about the street though,usually that power is useless on the street.
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Great info there.i mentioned going t4 as well.
T3s tend to choke around that power level.
T4 with a smaller AR will work same as t3 with a bigger AR.BUT the t4 has room to grow and t3 doesnt.
So if the OP gets tired of the power,theres alot more power on the table with the t4 platform since its less restrictive.
For sure. The precisions are likely rebuildable from 62's to 76's if you have the t4 housings.
I know my comps can be built from the 62/65's they are upto about twin 76's iirc.
It's nice to know that they have room to grow if I ever go auto/turn it into strip car.
For now it's my cruiser/fun car but that gt350 is calling my name...
I know my comps can be built from the 62/65's they are upto about twin 76's iirc.
It's nice to know that they have room to grow if I ever go auto/turn it into strip car.
For now it's my cruiser/fun car but that gt350 is calling my name...
Are you referring to 3" up pipes or downpipes?
I ran 3.73's with my t-56 and it still spooled up fast and was a lot of fun with my 7675 precision. Made 702/670 on 15psi. and a very safe tune. stock 99 cobra intake.
Unless the OP wants to become a drag car making 1200rwhp he does not need the added lag from the T4 flange. With his current setup, there is no advantage and a lot of disadvantage to going something out of it's compressor range.
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