What lower to run with a 2.93 and idlers?

[Om3ga47]

My setup:
2.93 SC pulley w/ idlers and snub
JLT cold air
BBK offroad x
Magnaflow catback

Question is what lower should i run?I want to be over 500 whp,as well what will the outcome be if anyone has done somthing similar and also will i need to order another belt? I currently have the 75.5" recommended by billet flow.

 

[slo-poc]

mods in sig...go 4# lower....get a port too well worth it bud!!! dont forget fuel, and maf also....

 

[Johnboy22]

Someone correct me if I'm wrong, and I know there are alot of other factors that could change it slightly but wouldn't a 6#lower put him around 15psi? I would say 6#. port, and 60# injectors . That would be a good start.

 

[EVILNSS]

i had a 2.93 upper and a 6lb lower with 60lbs injectors and MAFia and GT pumps b/c i wantd them and a stage 4 stig and i cranked out 522/560 on pump gas...

 

[Om3ga47]

whats a good website that will have almost everything for an 03-04 cobra

 

[CobraMac]

Here is a chart of the pulley combinations and the amount of boost you will be putting out. I have a stage 4 Stieg port a 2.93 upper and a 4 lb lower. It's all going on the car on wednesday so I will put my numbers up the next day. After talking to MANY people about this I decided to go with the 2.93/4lb combo because it runs at a boost level where the eaton is most efficient. According to suggestions from Stiegemier you are over-working the eaton once you get into the 16-17 lb boost range. Many others I've talked to have looked into this too and found the same results. Obviously eatons aren't anthing like whipples or KB's so we can't run the high boost they can and not worry about hurting the blower. As you can see, the 2.93/4lb combo puts a little over 15 lbs. of boost. With this combo and port I will definitely be over 500hp. Just my advice, be safe and stay below 16lbs.

 

[$ickZ06]

Go with a 4lb for sure! You will need a longer belt as well as an alternator pulley so that you don't overspin the alternator.

 

[Om3ga47]

Would my 75.5'' belt be ok for the 4lb or should i return it and reorder?
Gator back # 4080755
i have the full billet flow kit and snub

 

[$ickZ06]

whats a good website that will have almost everything for an 03-04 cobra

www.stangshiftergaskets.com

It's CobraBob's website. Read the FAQs. It's everything you want to know.

 

[CobraMac]

CobraBob's website is a HUGE help for this stuff. Like superchargedsnake said you need a new alternator pulley. I forgot to add I have the BF 4 piece 100mm ilders and tensioner and a 3.2 (4 lb.) alternator pulley. The alternator pulle is a necesity

 

[Om3ga47]

Here is a chart of the pulley combinations and the amount of boost you will be putting out. I have a stage 4 Stieg port a 2.93 upper and a 4 lb lower. It's all going on the car on wednesday so I will put my numbers up the next day. After talking to MANY people about this I decided to go with the 2.93/4lb combo because it runs at a boost level where the eaton is most efficient. According to suggestions from Stiegemier you are over-working the eaton once you get into the 16-17 lb boost range. Many others I've talked to have looked into this too and found the same results. Obviously eatons aren't anthing like whipples or KB's so we can't run the high boost they can and not worry about hurting the blower. As you can see, the 2.93/4lb combo puts a little over 15 lbs. of boost. With this combo and port I will definitely be over 500hp. Just my advice, be safe and stay below 16lbs.

What size belt and part number you running?

 

[CobraMac]

What size belt and part number you running?

This is the belt I ordered for my setup: Goodyear Gatorback GTR-4080810 . It's an 81" belt. I went off of CobraBob's belt size chart. I will talk to my tuner again tomorrow to make sure it's the correct belt. I completely forgot to ask him. Here's the link to his chart: http://stangshiftergaskets.com/BeltSelectionGuide.htm

 

[Om3ga47]

This is the belt I ordered for my setup: Goodyear Gatorback GTR-4080810 . It's an 81" belt. I went off of CobraBob's belt size chart. I will talk to my tuner again tomorrow to make sure it's the correct belt. I completely forgot to ask him. Here's the link to his chart: http://stangshiftergaskets.com/BeltSelectionGuide.htm

Did the 81" work?

 

[CobraMac]

I will find out for sure tomorrow. That's when i take it in to have everything done. So I will tell you tomorrow!

 

[CobraMac]

Okay, so that belt was the correct size. The 81" belt is the one you need. I get my car back tomorrow, but my tuner called me and told me it was the 81" belt!

 

[Om3ga47]

Ok thank you for letting me know,i returned the 75" at work today (autozone) and ironicly we had an 81 in stock so i grabbed it. Thanks again. Let me know how it goes and the numbers.

 

[F8L SN8K]

Eaton says max safe RPM to spin the blower is a 2.93. That is why I run a 2.93 on mine. Torque is dramtically different but power your pretty much maxed out just by a KB if 450-475 isnt enough. because 500 wont be either,

 

[CobraMac]

Not true at all, if you port the blower you are able to get your boost a lot higher and still be safe. With the mods I said above, I put down 509hp 507 ft/lb torque and that was with a safe tune. The eaton is not being overworked and is very efficient. From just intake and exhaust to a stage 4 port with a 2.93 and 4lb lower I gained 97hp and 121 ft/lb torque!

 

[slo-poc]

I'm at 17-18 psi with my combo.......565 rwtq is fun with an eaton....

 

[WHiTE03MACh]

+1 for 4#