2K C5 Fast Intake

[cruzc5frc]

I talked to a local performance shop about a Fast intake for 2K C5. I asked if I should go with Fast 90mm TB to compliment it, they said go LS6 TB due to the bolt lineups. Anyone to concur or clarify?

[Eagle]

Until you have supporting mods, the 90mm is over kill. The TB alone will cost ya another ~$450! The 78mm TB can handle 500HP with a lil porting & polishing that someone should be able to do for you for around $150 with the bump stop mod included.

However, if you plan to do forced induction, heads/cam/rockers, and full exhaust upgrades then the 90mm starts making sense if your wallet can swing it.

-Eagle

[NemesisZ06]

I agree with the above.

[cruzc5frc]

Agreed, LT headers is top on the list

current mods:
corsa pace car setup w/ corsa xpipe
KN cold air intake
short throw stick
replaced audio system, new alpine head unit, alpine type R 6.5" all around, 10" Alpine Type R sub, 2F CAP, MRP-F550 4 channel amp, MRP-F850 bridged to two ohm to power the single 10. (go loud parts)

[powermad]

Fast opinions:

Great intake when going big N/A (450+ RWHP).
Great for porting, expensive for what it is but when done by the right people can show impressive gains throughout the RPM band well worth the cost.
Not so much gains in F/I, some people have mentioned the possibilty of boost leak since the unit is not one solid piece.

If you put a FAST 90 you need a 90mm T/B. I believe the FAST 78 works with stockers but I am not sure. If you are doing a FAST though go all the way and do the 90 setup. I had bought a used FAST 90 with a Mamo port job and a 90mm Nick Williams T/B for 1150 but decided to put on a blower and sold the setup, never got to see what it did but others estimate that I would have picked up 20-25 at the wheels throughout most of the RPM band. This was over an LS6 intake with a Shaner ported T/B.

I will always wonder......

[DBN]

The GM LS6 intake is worth about 10 hp over your factory LS1 intake. Unless you perform several other mods such as heads, cam, headers, etc., you will not see an appreciable gain, and possibly a loss, with the FAST intake and TB. If you do go with the FAST, the 78mm will not give a noticiable gain over the LS6, however, if your car is heavily modified, the 90mm FAST intake and TB will give a noticable increase in power and torque throughout the entire rpm range. I gained 18 hp and 18 tq when switching from the LS6 to the 90mm FAST but my car was heavily modded and the intake was the restriction at that point.

[Frosty]

I agree with what was said. a FAST 90 is overkill on a relatively stock motor.

[ApexVIII]

The GM LS6 intake is worth about 10 hp over your factory LS1 intake. Unless you perform several other mods such as heads, cam, headers, etc., you will not see an appreciable gain, and possibly a loss, with the FAST intake and TB. If you do go with the FAST, the 78mm will not give a noticiable gain over the LS6, however, if your car is heavily modified, the 90mm FAST intake and TB will give a noticable increase in power and torque throughout the entire rpm range. I gained 18 hp and 18 tq when switching from the LS6 to the 90mm FAST but my car was heavily modded and the intake was the restriction at that point.

i would go with the stock ls6 intake.

[Wheeler99WS6]

I dont think a LS6 TB will bolt up to a FAST 90mm, I believe the bolt pattern is different. I believe that was your original question.