Opinions on SLP C/I Intake

  • Thread starter Thread starter Rusjet19
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Before I order it, I was wondering if anyone here has the SLP C/I intake for their cars. If so I would appreciate any feedback you could provide on this intake. Thanks!
Since you have a 2000 (better airbox design than 97-98), I would "port" the stock airbox, put in a K&N drop-in filter, and spend the $$ somewhere else, if it was me......
I "ported" my stock airbox as Tim described with a Dremel tool and ran a 4" duct all the way through it. The MAF-to-airbox connection uses a 10" long/4" diameter flexduct from Pep Boys, that when compressed, looks somewhat factory. Underneath the duct is a black PVC pipe coupler pushed through the hole I've enlarged in the back of the airbox. I lined the edge of the enlarged hole with a small piece of door edge molding to get a nice smooth edge. The 4" duct then connects to the other side and travels forward through the airbox and out the enlarged hole in the front. The hose then makes a turn behind the headlight and drops down into the wheelwell behind the foglight, in front of the left front tire. A 9x4" K&N is affixed to the end using a coupler. The hose behind the headlight is hidden by a small rubber flap I made; I installed a matching one behind the PS headlamp so they both look the same to the untrained eye.

So, the net effect when you open the hood is you see the stock airbox and the "kinda ugly"-looking duct that the factory uses. 'Course, when get on it, the s/c whine coming from the LF is a real eye-opener, especially to the driver who happens to be on your left.

Hope this helps,
'99 Buick Regal GS (14.22 @ 98.1; $7 manual fan switch, hot-wired fuel pump, AFPR (I rarely use it), 160 t-stat, TR55 plugs at .055 gap, custom CAI and exhaust w/factory muffler, 3.4/3.25)
'87 GN (11.1s @ 120)
'96 Buick Roadmaster Ltd Collector's Edition LT1 with a few mods
'67 Buick GS California (beautiful original FOR SALE :()

Did you see any changes in performance or fuel economy when you switched to the NGK TR55 plugs?

98' Regal GS..14.34 @95mph
Hi, I'm also working with a '99 GS.

I just removed my stock airbox and in looking at the design have decided to modify it so a 16" cone filter will fit. (Probably soon, and I plan on taking pictures) There is a 4" duct inside of the huge airbox that gets air from behind the headlight. Most of the box is an air cavity in which the pcm computer is located.

I didn't plan on extending a duct to the foglight area. But I do plan on gutting all the extra plastic walls. I plan on putting the computer in the same stock location (it fits well in the bottom of the airbox (I havent seen an older Regal or GTP airbox, but they must be radically different as my PCM is no where near restricting airflow) ).

My question to anyone that might know or have an opinion: Is it better to have a single inlet OR not only have that forward inlet but also a few blow holes on the side?

The whole point is to make the filter less restrictive but is it better to give it only fresh air or allow it to get air where it wants?

The TR55s are one range colder than stock, sorta like switching to the de rigeur R43TSs on a slightly modded Turbo Regal. Most prefer the gap at 0.053 to .055. The plugs helped reduce the KR a bit and mileage didn't suffer too much. I will say that the 3.4 & TR55s worked very well with the CAI & custom exhaust; the car would pull like hell on the street and was a lot of fun to drive. I say "was" as I'm now running a 3.25 & a set of Autolite 104s and frankly the car feels slower even though the timeslips don't bear that out. I plan on going back to the 3.4 seeing as the quality of our premium gas keeps dropping; the max we can get is 91 octane.

Hope this helps,

Thanks for the reply. I'm also running the 3.4" pulley for now. Car does pull great on the street too! However I noticed even when using 93 octane fuel, I'm still getting 7-15 deg. KR, according to my Auto-Tap scan info.( stock factory spark plugs).
I was thinking of trying a 3.0 pulley just for the track, using 100 oct. no-lead. You might see(feel) a greater improvement if you up your octane( if you can find some 100oct no-lead) as octane seems to be more crucial than volume of fuel at this stage.
My O2's were plenty rich on the Auto-Tap scan too. I had previously thought I probably needed more fuel, but that doesn't seem to be the case, rather more octane( for now anyhow! ).