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CJLightning04
12-15-2006, 12:43 AM
Ok I'm putting a few mods on next weekend if everything goes right and i was wondering what you guys think i might run. The truck dyno'd 360hp and 470tq and the best run was a 12.9. I haven't ran a 12 second pass since then. My goal is to stay with the eaton and run 12.5's or better so i can put a 50 or 75 shot on it to get into the 12.0 or high 11's

current: 6#L, SCT (tuned by Terry), Bassani catback, Tr6, K&N CAI, traction bars, 28" MT E/T

new: FTVB w/ 4x4 pan, ported blower (done by Walt), Ba2400

Walt usually sees about 1.5 to 2 lbs of boost with his ports and i run 14# right now. Also before i put the MAF on of course i am bringing it back to terry to get another tune.

Another question is,with running that much boost should i cut the rear cats off of my stock mids to relieve some of the back pressure.

Thanks for the input
Clay

CJLightning04
12-15-2006, 03:44 PM
anyone?

WA 2 FST
12-15-2006, 03:56 PM
Clay,

I think once we start going over 15-16psi on the stock block (no matter the blower) we're pushing the envelope. So I understand your thinking (and agree with the premise) behind trying to open up the exhaust somehow to lower boost... althewhile flowing more air.

I haven't tried exactly what you're proposing, just removing the cats from the stock exhaust. I did long tubes and do not run cats currently (didn't want to waste $$ on hi-flow converters that typically burn up pretty quickly anyway).

Have you considered biting the bullet and getting headers?

CJLightning04
12-15-2006, 04:08 PM
I really wasn't planning on getting headers for awhile. I really don't have the money right now. Thats why i was looking to open up the mids. I might be able to pull off getting cats less mids in a couple of weeks but i would have to see...it all depends on work

WA 2 FST
12-15-2006, 04:36 PM
Hopefully someone will have some quantifiable data for you. I couldn't find a good answer to your question when I was planning my KB install, except to do the whole exhaust. Anything else seemed to be negligible in terms of accomplishing what you're trying to do.

CJLightning04
12-15-2006, 11:07 PM
does anyone know if cutting the rear cats out of the stock mids will help with the amount of boost i will be running??

wesman
12-15-2006, 11:30 PM
does anyone know if cutting the rear cats out of the stock mids will help with the amount of boost i will be running??

It will definitely relieve backpressure....I doubt that it will affect boost levels that far back. The headers will, I don't think the cats will be as noticeable on boost levels.

--wes

Silver_2000
12-15-2006, 11:52 PM
I would run LESS BOOST tilil you can afford to do it right
Other wise it could easily cost you a lot more
Doug

CJLightning04
12-16-2006, 03:03 AM
so would bassani mids w/o cats help or am i giong to just have to buy LT

Sixpipes
12-16-2006, 10:15 AM
Long tubes are good ...:cool:

Silver_2000
12-16-2006, 11:21 AM
shop for used long tubes

Its possible to get under 12.5 with less boost

You need the tranny and the traction to make it happen

as far as I know catback only changes the sound

03LightningRocks
12-16-2006, 11:40 AM
snip.......

as far as I know catback only changes the sound


Pretty much what I experienced too. Long tubes didn't do a whole lot for my times either. The other mods, that making these changes allow us to do, are where the gains are had............:burnout:

Silver_2000
12-16-2006, 12:08 PM
Pretty much what I experienced too. Long tubes didn't do a whole lot for my times either. The other mods, that making these changes allow us to do, are where the gains are had............:burnout:

6# with long tubes is better than 6# without

6# with catback is IMO the same as 6# without

Doug

03LightningRocks
12-16-2006, 01:15 PM
6# with long tubes is better than 6# without

6# with catback is IMO the same as 6# without

Doug


No doubt about it.....:bows.

Silver_2000
12-16-2006, 06:01 PM
another piece of data

In 6 years of watching lightnings I have seen nearly 10X the blown motors with 6# pulleys as I have seen with 4# pulleys

Its anecdotal data but its what I have seen

Doug

SVTJoseCuervo
12-16-2006, 06:25 PM
I just got my 4lb in the mail...scared to put it on now :( ...i will take it to Terry as soon as i get back from the trip probbly

03LightningRocks
12-16-2006, 06:34 PM
I just got my 4lb in the mail...scared to put it on now :( ...i will take it to Terry as soon as i get back from the trip probbly


Read what Doug said about the 6# vs 4# pulley. Most of the time a 4# pulley in itself is not enough to pop a block. I would highly recommend a proper tune with the 4#, but I would not worry too much about blowing the motor on a 4#. With a proper tune, that is.

CJLightning04
12-16-2006, 07:22 PM
yea i have seen that too but usually they are when the shift into OD at WOT. Did you guys put the LT on yourselves or did you pay someone to

BC Lightning
12-16-2006, 07:28 PM
6# with long tubes is better than 6# without

6# with catback is IMO the same as 6# without

Doug

I just switched back to my 6#er from my 8#er while installing the new I/C pump

Mark #2
12-16-2006, 07:30 PM
yea i have seen that too but usually they are when the shift into OD at WOT. Did you guys put the LT on yourselves or did you pay someone to
Did it myself, putting them on is not the issue, getting the stock exhaust off in one piece requires getting the front end up to about 30 inches. If you cut the stock drivers side mid pipe it makes it much easier.

Silver_2000
12-16-2006, 07:52 PM
Read what Doug said about the 6# vs 4# pulley. Most of the time a 4# pulley in itself is not enough to pop a block. I would highly recommend a proper tune with the 4#, but I would not worry too much about blowing the motor on a 4#. With a proper tune, that is.

The number of blown motors running 4# pulley are very small
If you reduce that by the 140 mph blasts and the cazy tunes including stock predators, or wild warm tunes in the winter. The number of ventilated blocks from the remaining 4#ers is REALLY really small

TXLIGHTNING
12-18-2006, 04:37 PM
The number of blown motors running 4# pulley are very small
If you reduce that by the 140 mph blasts and the cazy tunes including stock predators, or wild warm tunes in the winter. The number of ventilated blocks from the remaining 4#ers is REALLY really small The man speaks the truth. :tu:

CJLightning04
12-18-2006, 06:47 PM
i rarely go over 100mph and i drive pretty safe when it is cold. The main thing i am worried about is at the track in cold weather

WA 2 FST
12-18-2006, 08:11 PM
Bottom line from all the research I did before doing the KB (and I had a 4# pulley on mine for a long time, and ran a 2# on my '99 for many, many years)... keep boost under 15psi and ~450-460rwhp max and _with a good tune_ the stock block will last a long time. Go over these two thresholds and YMMV substantially.