I am thinking about putting some SLP runners on but i was told that they wern't any better than stock. Does anyone have them and if so did they make a noicible gain/beter times at the track. I have almost all the bolt on's just need a little more to get me into the 13.9's i am running 14.218 now. Let me no what you think.

 

if you really want to dip into the 13's you could go with a set of 3.73 gears thatd should be enough to put you there but just to be safe id put a shift kit in there too so your not loosing as much power between shifts

 

I don't have them, but have seen the results...Question do you mean the large tube runners or the siamesed runners??I don't know anything 'bout the large tubes but the siamesed runners work quite well, but they aren't that great right out of the box....for the maximum effect take a die grinder to them and smooth them as much as possible and grind down the center ridge, if you haven't ported your plenum yet I suggest doing it at the same time and siamesing the plenum runners just like the runners...if all this is done at the same time you will feel a hellava diff and I'd say at least 2-4 tenths if not more (hate to over shoot would rather be conservative with the estiment) it will move your horsepower higher up the rpm band and really wake up your car at the end of the track, getting you your 13 run.

 

click here www.fl-thirdgen.org/mrr23 and go to the dyno sheet section. dyno 14 to 15 is the swap from LT1 cam, stock runners, and siamesed stock base to ZZ4 cam, slp runners(i completely siamesed), and edelbrock base.

 

in this months issue a 86 firebird with a 5.0 tpi dynoed 5 extra horse power with the siamiesed runners but of course they work better on bigger motors