vortech t-trim pulley size question

[98 Saleen Cobra]

I went with a a 3.2" alt. pulley with the 10%, so I would think 3.5" with a 15%.

You won't need a 15% overdrive with that 2.9" pulley man. You will be overspinning that blower by quite a bit, and it probably won't hold up to that for very long. With a 10% overdrive and a 3.0" blower pulley I will be at max impeller speed at 6500rpm, and I have the same blower as you. Plus, if you are looking for 17lbs. of boost, you will get that with the combination I have on mine. The max impeller speed for our blowers is 55K. Even if you only spin your motor to 6500rpm you will be at 58K. If you go to 7000rpm you will be at almost 63K. You aren't going to need to spin it that hard to reach your goal. If you feel like you have to get a 15% overdrive, I wouldn't go any bigger on your blower than 3.2". That will put you at max impeller speed at 6500rpm and at 57K at 7000rpm. Its not worth destroying your head unit.

He's not going to destroy his head unit by overspinning it. People over spin the T-trims and S-trims all the time.. Two people I know overspin the tiny s-trim by 10k rpms.. Is it out of it's range? Yes but will it explode no it won't.. Unless he stays at 6500 rpm for extended periods of time which I doubt he will..

Also if you aren't running a intercooler of some sort on your setup which it looks like you are using water meth injection that pulley combo won't be the same for him.. Since he's running a aftercooler there is still some boost loss with his setup, unlike yours.

If he has full exhaust like LT's and a full o/r xpipe he shouldn't need to pulley down anymore than a 3.33'' blower pulley and the 15% O/D that'll be right around 17psi for his setup.. If he isn't running full exhaust or stock logs that number will probably be closer to 19psi which I wouldn't recommend running on 93 octane. But we also need to know what RPM he plans on spinning to. If he wants to go to 7k then that's different than 6500rpm as you mentioned above. :beer:

 

[JP_Stang]

I run a Bell intercooler also, so I will have the loss. I agree with your pulley combo, I just said that I wouldn't run anything under a 3.2" blower pulley with a 15% overdrive. I am just telling him what his impeller speeds will be at certain rpms so he can make the judgement call on what pulley combo will be best for him.

OP, I am not trying to get you to not go with the 15%. I am only sharing information that I found when I was at the point you are at right now. I had several people tell me that the 15% overdrive's caused their water systems to over pressurize. The only thing it really caused for them was the fact that they couldn't keep radiator hoses from popping off. I just didn't want to have to deal with that so I went with the 10%. With that being said, 98 isn't the first person to tell me that he didn't have this problem so obviously there are people out there running the 15% with stock water pumps and not having any issues.

As for the head unit overspinning comment, I am that guy who doesn't like to push my parts to the extreme limit (anymore ). I am not rich by any means and I live on a budget with a family I have to support also. I love cars and they are my passion, expecially Mustangs. So when I build a car and put this kind of money into it, I just want to make sure that I do everything on my part to make sure that the car and its parts last as long as possible. Being in this hobby, it is certain things are going to happen and being "safe" with my parts doesn't mean something won't give out, and I am aware of this. It is just part of it. I am just sharing my opinion with you. So when I tell you about the limit of your head unit, I am sharing what Vortech recommends, not what it may actually do. It is just the protective side I have towards my builds. I just can't afford to gamble with it like I used to do. When I was single, I would have spun that baby to the moon! I just can't afford to take that chance anymore.

Any how, it is just my 2 cents.

 

[98 Saleen Cobra]

^^ Pretty much everything you said is right. I didn't know you had a intercooler I was judging it off of your sig. My bad :beer:. I don't push my the limits of my blower either.. I'm a little below max impeller speed at 7k. and I'm making the numbers in my sig on 17psi and pump gas. It's enough for me and I can still pump timing up and run 100 octane and make probably another 30 more hp. It all depends on how much you want and if your current setup is efficient enough as well. :beer:

 

[super98snake]

havent got a bypass valve yet but im prolly going to run long tubes with an x to my super 44 flowmasters what bypass valve is good for this setup?

 

[super98snake]

so it sounds like i need to make the decision between a 15% overdrive with a 2.9 or a 10% overdrive with a 3.0? both with a 3.5 alt pulley

 

[super98snake]

not sure if it makes a difference if im running with the a/c im not eliminating that

 

[98 Saleen Cobra]

You don't need a 2.9'' pulley with a 15% O/D crank pulley. That's waaay to much.. You'll be at like 23psi with that pulley combo. You need a 3.33'' blower pulley and a 15%O/D crank pulley.. If you do a 10% O/D crank pulley the probably a 3.1'' will be ok.

For a bypass valve you're more than likely going to have to go with a custom setup of somesort.

 

[JP_Stang]

What 98 said about the pulley sizes. A 15% is going to spin everything harder because it is larger than a 10%. If you go with a 10%, a 3.2" alt. pulley will be big enough. If you go with a 15%, you will want something around 3.5" for the alt.

Since you will be pushing quite a bit of boost, I would look into a Procharger big red bypass valve if you are keeping it a bypass valve. If you decide to vent to the atmosphere you could do Procharger's big red BOV, Tial 50mm or something along those lines. If you go Tial make sure to get the pink 3psi spring for it which is designed for the centri blowers. Also, if you vent to atmosphere you will need to convert to blow thru on your MAF.

 

[super98snake]

alright thanks for the help where should i get these pulleys from? and should i do what jp did and go with 2-255 pumps i only have one in the tank right now nothing external

 

[98 Saleen Cobra]

You can get the O/D crank from lethal performance and the vortech pulley from vortech. as for pumps. You will probably need a 255 intake and 255 inline.. Or even better 2-255's in parallel

 

[JP_Stang]

^^^Agreed. If you can afford to go with 2-255 in parallel that would be ideal. As soon as I get my car tuned after Christmas, I am saving up for a dual fuel hat, lines, rails and FPR to complete my fuel system. That way I don't have to worry about it anymore. Mine is setup with one intank and one inline right now. I believe that will be my weakest link when going for 600whp.

 

[98 Saleen Cobra]

You should be able to hit 600rwhp depending on what size injectors your have, rails, and feed and return line size..

 

[JP_Stang]

I think the pumps may get me there anyway, but they would have a better chance if I had the rest of the fuel system complete. I am going for it with the pump setup mentioned, 60lb. injectors, Aeromotive FPR and stock lines and rails. It may not get there this time around. I am going to have it tuned anyway just so I can go out to atleast cruise around in her. When tax returns come back I will be completing the fuel system and running one external pump. I am debating on going with bigger inj. and converting to E85 since it is available around me. Haven't made up my mind yet on that tho.

 

[98 Saleen Cobra]

You'll be close that's for sure.. My old setup ran outta fuel at around 575rwhp.. It consisted of stock intank, 255 inline, stock lines, FORE rails with 60lb injector and a Aeromotive FPR. Every car is different though..

My opinion on your next fuel system is if you're even thinking about E85 build it for that. Get it done and over with lol. :beer:

 

[super98snake]

im just going to run the 255 in tank with 60lb injectors and hope for the 600rwhp i just dont see the funds happening between now and when its done for 2 fuel pumps i got a motor to complete and a trans to rebuild before i think about driving it

 

[98 Saleen Cobra]

No way in hell will you hit 600rwhp on 1 pump bro sorry.. I'll bet you make 450rwhp before you run outta fuel..

 

[Chances50]

Not to jack this guys thread but what kind of boost should a guy expect with a 3.1/6.5 combo on an intercooled S trim? I have full exhaust and a built motor in a 03 Mach. I'd like to see 14-15 once I swap to a treadstone Intercooler. And 600+ on e85.

 

[98 Saleen Cobra]

If that size is a stock lower you'll be around 14 psi depending on exhaust combo. Maybe a bit less through the intercooler

 

[Chances50]

Sweet. Accroding to treadstone thier intercoolers have less than 1.5psi drop. Yes that is stock lower. Might get a 10% to get 15-16 out of it.

Thanks

 

[Chances50]

Stupid iphone