Are T.O.G. headers any better or easier to install than SLP headers? Does either one need to go to an aftermarket cat or downpipe. I would like to use the best kit performance wise even if it means replacing the OEM cat. Is it possible to retain the stock cat with either of these kits? Any advice greatly appreciated!
The SLP headers have not been out long enough to get enough information about them IMO. The TOG headers have been out a while and are proven, but they cost more money. Neither headers need a different cat or downpipe, but I would highly recommend one. The TOG headers are supposed to have larger pipes than the SLPs, but that may not necessarily be a good thing, depending on your mods. I don't think either header is more difficult to install than the other, it basically is just which one you like better. I definately recommend getting a ceramic coating on them though, because it will drastically reduce underhood temps. We have Ceramic Coated TOG'* on our GTP and they look & perform very great. IMO the TOG'* are better just because I have personally seen both in person and the SLP headers have sharper bends in them, and have smaller diameter pipes.
1990 Maroon Grand Prix STE McLaren 3.1 Intercooled Turbo, 14.695 @ 94.49 on 12psi before cam/heads/etc.
1990 Bright Red Grand Prix McLaren 3.1 Intercooled Turbo, 14.819 @ 92.72, 189whp
1999 Grand Prix GT 9.75:1|K&N|160 tstat|No Ubend/Cat/Res|UD Pulleys|Ported M90/TB/Heads|XPZ|2.55"|Pacesetters|Stage 2 I/C. 12.442 @ 112.78
2000 Blue Bonneville SSEi Supercharged Gutted Airbox|K&N|3.4"|1.9'*|WP Pulley|Custom DHP|180*stat|41932'*|No Cat. 14.681 @ 94.80
2002 Dark Cherry Grand Prix GTP Supercharged & Intercooled
12.084 @ 114.38 w/1.743 60', 315.6whp, Fastest Stock Cam M90 GTP!
NOW XP CAMMED, 340.6whp with XP, stock heads, Gen 3 M90, 11.984 @ 115.84 w/1.750 60'!
Most HP Stock Heads Gen 3 M90 GTP!
2004 Red Monte SS Supercharged K&N|3.4 Pulley|1.9'*|180*stat|41919 plugs|3" dp|No cat/ubend|DHP|Shift Kit. 14.2 @ 98
GOT BOOST??? Friends dont let friends drive stock!