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Just ordered a KB 2.6L kit few questions

  • Thread starter Thread starter stangJunkie04
  • Start date Start date Jan 13, 2009

stangJunkie04

New Member
Jul 11, 2005
44
1
0
Vernon, CT
Jan 13, 2009
#1
  • Jan 13, 2009
  • #1
I just ordered a KB 2.6L kit for my 04 GT, I am replacing my vortech s-trim with the unit. I had a few questions:

1. Currently I have 4.10 gears which I know is way too much gear for the KB so what would be a good rear gear to go with 3.73 or 3.55

2. I am planning on running 20psi however the KB representative said that he would include a 18psi and 20psi pulley due the fact that anything over 18psi (pulley wise) should not be used in traffic or on trips extending over 30-40 miles due to over heating the compressor, and that I should just swap the 18psi pulley with the 20psi when I get to the strip or when I want the extra boost. Does anyone have any thoughts on the validity of this.

3. I installed my vortech kit myself I was just wondering if anyone had any expereince on the kb install is it pretty straight forward? any helpfull tips or things to watch out for would be greatly appreciated.
 
X

xsoutherngun89x

New Member
Dec 8, 2008
10
0
0
montgomery, AL
Jan 13, 2009
#2
  • Jan 13, 2009
  • #2
1st off, im pretty jealous lol.

2nd, if it was a kb rep he SHOULD know what he is talking about but not everyones an expert. might want to ask your dyno tuner what he thinks.

if it was me id go 3.55s, kbs dont have any lag like the centris.

cant help on the instal, as ive never put one on.
 

stangJunkie04

New Member
Jul 11, 2005
44
1
0
Vernon, CT
Jan 13, 2009
#3
  • Jan 13, 2009
  • #3
xsoutherngun89x said:
1st off, im pretty jealous lol.

2nd, if it was a kb rep he SHOULD know what he is talking about but not everyones an expert. might want to ask your dyno tuner what he thinks.

if it was me id go 3.55s, kbs dont have any lag like the centris.

cant help on the instal, as ive never put one on.
Click to expand...

yeah I guess your right I will just ask my tuner after I install it.
 
0

'03GTinFLA

Member
May 29, 2004
486
0
17
St. Petersburg, FL
Jan 13, 2009
#4
  • Jan 13, 2009
  • #4
The install is long and I had a few head scratcher moments but the instructions couldn't really be any better. Almost every step has a picture with it and it walks you through it step by step. I did my with help from a friend and it took about 2 days. We were screwing around a lot too. Plan for a weekend, take your time and have fun. You'll love it.
As far as gears go, I have a 1.7 with 3:73's and I was thinking of going with 3:55's or back to stockers. Mine is a DD and with 3:73's I can spin 1st, 2nd and into 3rd if I want. 1st gear is basically stupid if you just floor it, unless you like shooting straight to redline with a smoke show behind you. My main issue with gears is that 1st is short, my car is loud and people always think I'm trying to race them when I'm just driving. I also got pulled over recently because the cop thought I was "hot rodding". WTF?
As far as the pulley thing, I would go what KB says. Just because you won't notice that much difference with 2 psi for everyday driving and then you'll have the 20psi for when you need it.
Just my .02
 

stangJunkie04

New Member
Jul 11, 2005
44
1
0
Vernon, CT
Jan 13, 2009
#5
  • Jan 13, 2009
  • #5
'03GTinFLA said:
The install is long and I had a few head scratcher moments but the instructions couldn't really be any better. Almost every step has a picture with it and it walks you through it step by step. I did my with help from a friend and it took about 2 days. We were screwing around a lot too. Plan for a weekend, take your time and have fun. You'll love it.
As far as gears go, I have a 1.7 with 3:73's and I was thinking of going with 3:55's or back to stockers. Mine is a DD and with 3:73's I can spin 1st, 2nd and into 3rd if I want. 1st gear is basically stupid if you just floor it, unless you like shooting straight to redline with a smoke show behind you. My main issue with gears is that 1st is short, my car is loud and people always think I'm trying to race them when I'm just driving. I also got pulled over recently because the cop thought I was "hot rodding". WTF?
As far as the pulley thing, I would go what KB says. Just because you won't notice that much difference with 2 psi for everyday driving and then you'll have the 20psi for when you need it.
Just my .02
Click to expand...

Thanks for the info I appreciate it, I am sure me and my buddy will have a good time installing this bad boy.
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Jan 13, 2009
#6
  • Jan 13, 2009
  • #6
stangJunkie04 said:
2. I am planning on running 20psi however the KB representative said that he would include a 18psi and 20psi pulley due the fact that anything over 18psi (pulley wise) should not be used in traffic or on trips extending over 30-40 miles due to over heating the compressor, and that I should just swap the 18psi pulley with the 20psi when I get to the strip or when I want the extra boost. Does anyone have any thoughts on the validity of this.
Click to expand...

Well, it's coming from a KB representative but it sounds weird to me. When driving in traffic or on trips the engine RPM is normally quite low and thus the blower RPM is low. On the highway there will be manifold vacuum, not boost so it's not like the blower will be generating tons of hot air. Extended road-racing type driving I could see but daily-driving and/or highway trips?

What might make more sense is that the blower, when set up with a small diameter pulley, is spinning faster at all engine RPM than when used with a larger diameter, lower-psi pulley. This might result in the gear train, oil and bearings running hotter. Since the gear housing only holds something like 6-oz of oil, you need to be careful of the oil temperature since it can breakdown if it gets too hot and it can also damage the bearing seals leading to internal oil leaks.

You plan to run 20psi? What is your bottom end, clutch, transmission, driveshaft, rear axle, suspension and tire setup? That's a ton of boost and I'd imagine you must have a pretty impressive drivetrain, suspension and tire setup to deal with the power 20psi will deliver.

EDIT: N/M I just went and saw your cardomain page and see your setup is top-notch. Love the wheels BTW...
 

SVT32VDOHC

waiting for the next hack atta
Founding Member
Nov 22, 2001
3,501
28
119
Motor City
Jan 13, 2009
#7
  • Jan 13, 2009
  • #7
KB do not need the oil pan to be tapped. You will have to plug your hole in your oil pan now, or get a new oil pan.

With a KB and 18psi, I would step down to a 3.55 gear. 4.10 is too much as you know, but 3.73's will still be steep. I have an 04 Cobra with a 17psi Whipple with the stock 3.55's and the tires don't stand a chance in 1st, 2nd, or 3rd gear.
 

02LaserRed2V

New Member
Jul 30, 2004
379
1
0
Augusta, GA
Jan 13, 2009
#8
  • Jan 13, 2009
  • #8
I have 3:55s in mine and I personally think that's the best ratio for a twin screw setup.
 
M

mat82284

Member
Jul 31, 2003
889
1
16
Jan 13, 2009
#9
  • Jan 13, 2009
  • #9
stangJunkie04 said:
I just ordered a KB 2.6L kit for my 04 GT, I am replacing my vortech s-trim with the unit. I had a few questions:

2. I am planning on running 20psi however the KB representative said that he would include a 18psi and 20psi pulley due the fact that anything over 18psi (pulley wise) should not be used in traffic or on trips extending over 30-40 miles due to over heating the compressor, and that I should just swap the 18psi pulley with the 20psi when I get to the strip or when I want the extra boost. Does anyone have any thoughts on the validity of this.
Click to expand...

I can see many people dont know much about the twin screws, but these blowers are similar to the roots type blowers. They all heat soak, The twin screws do take longer but not as fast as the roots type. The problem is at 20psi your probably pushing that blower to an rpm level that is almost like having boost on at all times, even though you wont see it the blower is still outputting it. That where you bypass valve comes in and stops the boost from entering. Once a roots type or Twin type is heat soaked, you will loose hp. This is one reason i swapped to a Vortech, with 3.73s and a roots blower only pushing 370hp (crank) couldn't ever use first.
These blowers are perfect for street, but track is a little harder for them. The heat soak is the biggest downfall of any twinscrew/roots type blower. You will notice your IAT's much higher than with your Vortech and because of a hotter IAT it puts more ware on your engine and you have to cut timing, which causes the loss in hp. It usually takes 20mins of driving to feel the heat soak unless your in 90+ weather then its alot faster. I hope this gives you an idea why they suggested you not to do it. Now if your temps never go over 40-50 deg then i say you'll be fine because they are probably checked that blower at a common outside temp of 80-90 or so.
 

stangJunkie04

New Member
Jul 11, 2005
44
1
0
Vernon, CT
Jan 13, 2009
#10
  • Jan 13, 2009
  • #10
SVT32VDOHC said:
KB do not need the oil pan to be tapped. You will have to plug your hole in your oil pan now, or get a new oil pan.

With a KB and 18psi, I would step down to a 3.55 gear. 4.10 is too much as you know, but 3.73's will still be steep. I have an 04 Cobra with a 17psi Whipple with the stock 3.55's and the tires don't stand a chance in 1st, 2nd, or 3rd gear.
Click to expand...

Yeah I am definately going to have to plug the oil pan.
 

stangJunkie04

New Member
Jul 11, 2005
44
1
0
Vernon, CT
Jan 13, 2009
#11
  • Jan 13, 2009
  • #11
mat82284 said:
I can see many people dont know much about the twin screws, but these blowers are similar to the roots type blowers. They all heat soak, The twin screws do take longer but not as fast as the roots type. The problem is at 20psi your probably pushing that blower to an rpm level that is almost like having boost on at all times, even though you wont see it the blower is still outputting it. That where you bypass valve comes in and stops the boost from entering. Once a roots type or Twin type is heat soaked, you will loose hp. This is one reason i swapped to a Vortech, with 3.73s and a roots blower only pushing 370hp (crank) couldn't ever use first.
These blowers are perfect for street, but track is a little harder for them. The heat soak is the biggest downfall of any twinscrew/roots type blower. You will notice your IAT's much higher than with your Vortech and because of a hotter IAT it puts more ware on your engine and you have to cut timing, which causes the loss in hp. It usually takes 20mins of driving to feel the heat soak unless your in 90+ weather then its alot faster. I hope this gives you an idea why they suggested you not to do it. Now if your temps never go over 40-50 deg then i say you'll be fine because they are probably checked that blower at a common outside temp of 80-90 or so.
Click to expand...


Is methanol injection ever used with the twin screw s/c's?
 
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