i have a 1991 z28 L98. im planning on getting a set of slp runners, headers, custom ypipe, and a hooker cat back exhaust. and strap a 100 shot of juice on it. what kind power gains will i see and what kind of ETs. thanks

 

You should be running mid 14's with your almost stock L98 or better since you have the Speed Density car.... The mods you listed above should be good for around 25-30 hp. Et's should drop .5-.6 without nos. If you do the runners, do the intake manifold as well, and you will see much better gains. Not sure about the nos maybe you would drop off around a full second never tried the spray. I do know from experience Headers/Cat-back/runners/Manifold are good for around .5-.6 off your 1/4 times.

 

speed density doesnt like mods as much as MAF..

the custom tune will be crucial... but i'd say a solid 375-400crank hp on spray

 

True but stock for stock they were a tad quicker.

 

1 full second, to 1.5 off your E.T. with the nitrous will most likely be the result, with good traction.

 

True! Once, nitrous made my car run 18.55 @ 55 mph. Expensive day!

 

He's running a carb...

 

Who is "running a carb"??

 

I'm still running my factory prom. Then again, I'm still running the factory runners too.

I'd say mid-high 13's on the engine. Well into the 12's on spray. You may want to invest in some suspension mods and tires as well.

 

yeah but i bet there is some left in it. boltin on runners and new base and such will make power but i think MAF will respond better to those mods than speed density. not to say speed density cant take to mods, just not as well as MAF. its just what i have read around.

and the tune for the nitrous is really what will count

 

There may be a little but I trap higher than most cars I see with similar mods. I've read that a million times how MAF cars respond better but I don't see how you can actually prove it. I think it really boils down to the individual car. I've seen it go both ways. As far as tuning goes, I just use fuel pressure and base timing and it seems to work OK for me. I'd like to try a TPIS Big Mouth base and runners and add more fuel pressure and see what it does. Right now, my pressure's at 43 PSI with the bigger injectors. My engine has 206,000 on it now so I highly doubt I'll let it go another year without an engine build. I'll definitely need tuning then!

 

His L98 is still bone stock.....not carb'd thats his RS.

the SLP runners wont help too much without some porting on the intake manifold...then they'll pick you up quite a bit.

I say with GOOD full exhaust and N/A (provided you hook), you should be aorund high 13's with some practice runs.

What brand Nitrous you using? It makes a differance. If you use Nitrous Express/TnT, you'll get the hardest "hit". NOs doesnt hit as hard....their solenoids are too small. anything else is total junk.

If you get an NX wet kit and put the 100HP jets in, expect to drop a little over a second off your ET's...provided you hook. My buddy went from 13.6's to 12.4'/12.5's in his gears/exhaust 04 GT Mustang....on ET streets might I add. I know another buddy with an NOs 100HP wet kit and he went from 13.3's to 12.5's with a 12.48 best....he didnt pick up as much.

Aroudn here we really only have 1/8th mile.....and rule of thumb is, with traction, you'll gain a FULL second in the 1/8th with a 150HP wet shot......thats what Ive seen from 1 Mustang and a ThirdGen GTA.

I reocmmend an NX kit as I LOVE mine and cant wait to see track times next year