Anyone running a 2.4 upper and 15% OD?

[Shhhh]

I currently have a 2.4 upper and have been kicking around the idea of throwing on a lower. I know a few people on here run 10% OD's with a 2.4 upper without a problem on 93. I have been told conflicting things about a 2.4/15% setup and just curious if anyone already is doing this.

Does anyone run a 2.4 Upper and a 15% OD setup?

 

[Devious_Snake]

The 15 requires modification to fit if you have the track pack I believe is the main concern

 

[Shhhh]

The 15 requires modification to fit if you have the track pack I believe is the main concern

Track pack or not I believe you still have to grind off a tab for the 10% or 15% to fit.

 

[Devious_Snake]

Track pack or not I believe you still have to grind off a tab for the 10% or 15% to fit.

No the 10 will go on with no problem. Its the 15 that has fitment issues

 

[Shhhh]

No the 10 will go on with no problem. Its the 15 that has fitment issues

Gotcha, thanks :beer:


Still curious if anyone is running a 2.4/15% setup.

 

[BIRDDOC]

I seriously thought about it but after discussing it with Jon Lund gave the idea
up. You will produce way too much heat with the TVS since it will be so inefficient
at the RPM's you'll be spinning it at. That heat increases detonation and robs the power you would gain plus you would be pushing about 20lbs of boost. If you still decided to do it you would have to run
URT race gas..that's about 15-17/gal depending on how you get it. Thus, I decided not to
put an upper on mine in addition to my 15%OD.

 

[BIRDDOC]

Both the 10% and 15% require the crank sensor tab be ground down. The 15%
Requires the custom fab track pack fitting if you have the TP. My SVT mechanic has done both OD pulleys so actual info.

 

[Shhhh]

I seriously thought about it but after discussing it with Jon Lund gave the idea
up. You will produce way too much heat with the TVS since it will be so inefficient
at the RPM's you'll be spinning it at. That heat increases detonation and you would
be pushing about 20lbs of boost. If you still decided to do it you would have to run
URT race gas..that's about 15-17/gal depending on how you get it. Thus, I decided not to
put an upper on mine in addition to my 15%OD.

I've only put 100octane in the car since I picked it up from the dealer last June. Its about $7-$8 a gallon from the pump. Im leaning towards just going ahead and doing it and if I have too I'll step down to a 10%. Thanks for the information though. I'd still be curious to hear from someone who is running the setup and to see if it's worth it.

 

[Shhhh]

Both the 10% and 15% require the crank sensor tab be ground down. The 15%
Requires the custom fab track pack fitting if you have the TP. My SVT mechanic has done both OD pulleys so actual info.

Thanks. I thought they both needed a little work to be installed. Thanks for clearing it up.:beer:

 

[VNMOUS1]

Do the 10%. The heat you make from over-spinning that TVS will offset any extra power you make.

bj

 

[91svtbird]

I currently have a 2.4 upper and have been kicking around the idea of throwing on a lower. I know a few people on here run 10% OD's with a 2.4 upper without a problem on 93. I have been told conflicting things about a 2.4/15% setup and just curious if anyone already is doing this.

Does anyone run a 2.4 Upper and a 15% OD setup?

+1 on the best combo for max size pulleys would be using just a 10% lower pulley only with the stock upper because of max blower RPM and least amount of belt slippage which of course is lost HP. This is an old debate but the facts are still the same regardless of what some vendors are pushing to make a sale. You are already past that point with the 2.4 upper on there. Lots of other things that can be done to get more HP over spinning the blower isn't one of them.

(I posted this a while back)

The TVS's best RPM efficiency range is at about 18,000 rpm's....as it spins faster it starts to loose some efficiency. Anything above 20,000 is definitely past the blower's efficiency where heat soak will also become a major factor.

To put this in perspective @ 7,000 engine rpm's:

(1) stock 2.7 pulley will turn the blower .......@ 18,726 rpm's

(2) 10% OD lower pulley will turn the blower @ 20,664 rpm's

(3) 2.4 Upper pulley will turn the blower .......@ 21,145 rpm's

(4) 15% OD lower pulley will turn the blower @ 21,697 rpm's

 

[black03]

The 15% and 2.40 upper isn't going to be safe with 93 octane. Either a 15% by itself or the 10% with a 2.40" upper would be a much safer bet.

Give us a call if you have any questions or if you'd like to place an order. We have the parts in stock and ready to ship.

Thanks, Jared

 

[Shhhh]

Do the 10%. The heat you make from over-spinning that TVS will offset any extra power you make.

bj

Ya that was actually my big question. Thanks for the input.:beer:

+1 on the best combo for max size pulleys would be using just a 10% lower pulley only with the stock upper because of max blower RPM and least amount of belt slippage which of course is lost HP. This is an old debate but the facts are still the same regardless of what some vendors are pushing to make a sale. You are already past that point with the 2.4 upper on there. Lots of other things that can be done to get more HP over spinning the blower isn't one of them.

(I posted this a while back)

I remember seeing that. I was trying to look for it. Thanks for posting it again :beer:

The 15% and 2.40 upper isn't going to be safe with 93 octane. Either a 15% by itself or the 10% with a 2.40" upper would be a much safer bet.

Give us a call if you have any questions or if you'd like to place an order. We have the parts in stock and ready to ship.

Thanks, Jared

Ya I've never ran anything less than 100 which is why I was curious about a 2.4/15% combo.

You see people over spinning stock eaton '03-'04 Cobras(Different supercharger and cooling system I know) and making some serious power. Do they just get heat soaked after one run and start to pull timing?

 

[biminiLX]

So, which is better/safer/more boost?
10% lower + 2.4 upper

or

15% lower only

-J

 

[91svtbird]

The 15% and 2.40 upper isn't going to be safe with 93 octane. Either a 15% by itself or the 10% with a 2.40" upper would be a much safer bet.

Give us a call if you have any questions or if you'd like to place an order. We have the parts in stock and ready to ship.

Thanks, Jared

This is very bad advice no matter what fuel your on. A 10% lower with a 2.4 upper would be spinning the blower way past it's efficiency window at the extreme speed of 23,300 RPM@ 7,000 engine RPM. Even at 6,200 engine RPMs you are past the limit with 20,830 blower rpm's.
According to Eaton's own blower map the efficiency window for the TVS is 18K to a max of 20 thousand RPM's. Plus any boost level of 20lbs or more is also past the compressor map efficiency range.

 

[Shhhh]

This is very bad advice no matter what fuel your on. A 10% lower with a 2.4 upper would be spinning the blower way past it's efficiency window at the extreme speed of 23,300 RPM@ 7,000 engine RPM. Even at 6,200 engine RPMs you are past the limit with 20,830 blower rpm's.
According to Eaton's own blower map the efficiency window for the TVS is 18K to a max of 20 thousand RPM's. Plus any boost level of 20lbs or more is also past the compressor map efficiency range.

Just for my own clarification; The blower is becoming less efficient past 18K a.k.a. creating more heat per "horsepower". For a lack of a better term?

In your opinion you would only run a stock upper to stay within the efficiency window throughout the entire rpm range?

 

[BIRDDOC]

So, which is better/safer/more boost?
10% lower + 2.4 upper

or

15% lower only

-J

The 10% OD plus 2.4 upper will push about 18.5-19 lbs
The 15% OD will push about 17.5-18 lbs

So, the 15% OD would be the safer of the 2 based on boost produced and safety of using 93 octane. Also, even though "apparently" all 2.4 upper/10%OD lowers don't have belt slip many have which can be a real headache. Save yourself the headache and just go with a 15% OD if your b/t the 2 options.

So in the end..10% OD solo...safer than...15% OD solo...safer than...10% OD plus 2.4 upper

My 2 cents

 

[black03]

This is very bad advice no matter what fuel your on. A 10% lower with a 2.4 upper would be spinning the blower way past it's efficiency window at the extreme speed of 23,300 RPM@ 7,000 engine RPM. Even at 6,200 engine RPMs you are past the limit with 20,830 blower rpm's.
According to Eaton's own blower map the efficiency window for the TVS is 18K to a max of 20 thousand RPM's. Plus any boost level of 20lbs or more is also past the compressor map efficiency range.

I appreciate your opinion. However these are setups that we sell all of the time without any issues. It's a combo that our tuner is very comfortable tuning as well. With that said I feel completely comfortable recommending these setups.

I understand engine/blower rpm's and manufacturers recommendations and I'm not going to argue that. What I can say though is running a 15% lower by itself is almost the same as running a 2.4" upper/10% lower. Either combo works very well on these cars and hasn't caused any failures/problems to this date that I'm aware of. The only thing I don't recommend is running the 2.40" upper with a 15% lower with 93 octane. That's just too much boost for a lower grade fuel.

Jared

 

[Devious_Snake]

@birdoc or you can add long tubes which will likely lower you boost 1 psi making it even safer and you can run upper and 10 lower :burnout:

 

[biminiLX]

@birdoc or you can add long tubes which will likely lower you boost 1 psi making it even safer and you can run upper and 10 lower :burnout:

You beat me to it, was going to ask how much LTs and and O/R mid-pipe drops the boost. I would have guessed more than 1 psi.:shrug:
-J