IgorT.455/406

Hey guys. On a bone stock '87 350 TPI car, what is the best set of mods to do that won't cost too much or make the car run any different (reliablity wise and stuff). I have headers and a complete exhaut system, but that is all. What next? I am looking to shave about 1 second off the stock time. On my LT1 car, I did the mods in the sig and reprogrammed it using Tunercat, car gained a second at the track.

95redvert

The '87's had the poorly designed air intake. Get a CAI with a K&N from SLP or someone like that. Remove the screens in your MAF, add a tb airfoil, afpr (bump your fuel pressure to 48 or so), bump your timing to 10btdc or 12btdc and add some sticky tires and you should knock off a second. Maybe a little less or more depending on track and weather. And at the track between runs cool off the TPI intake with a bag of ice, it really does help improve et's.

IgorT.455/406

Hey, thanks a lot. Those mods sound good and easy. That is basically what I did to my LT1 plus a few more things.

krazzycowgirl

In Taking off the screens watch it, Some cars dont like them off. My 87 Iroc didnt like it when my husband took the ones off of his 87 Iroc & put it on my car.

for more Air cut the bottom of the airbox off.


Airfoils dont really help much.

If nothing else start thinking about a new intake system like the HRS or the Mini ram or even a LT4 system.

95redvert

A CAI will not need the airbox cut any more. And combined with a CAI, and ported MAF a airfoil helps alot. One of these mods alone doesn't do much, but put the package together and it works.

Igor - you could also grind down the walls behind the tb in the plenum. This will help improve airflow even more, and it is only easy to do seeing you will have to remove the plenum to install the new afpr.

AutoRoc

Bump Timing to 10-12 degrees at base and run premium fuel. Porting the inside front of the plenum is worthwhile, removing the lip on the floor of the plenum to be exact. A custom cold air kit locating a big cone K&N filter far away from the engine would be money well spent. Maybe do a 90 elbow from the throttle body into some 3.5" PVC or exhaust tubing routed towards the front drivers side of the engine bay. Remove the canister and stuff over there if you're willing and what not.

Sticky tires are a must for TPI cars. Making the car hook from a dead stop is so much more important with these engines because the more the engine revs the less power it makes. Goodluck man!

aklim

Get a new intake manifold and have someone like www.fasterproms.com adjust your eprom. Don't screw with the fuel pressure and timing because that is a dangerous way to do things. It increases fuel and timing across the board whether that point needs it or not. This is akin to having a buying a suit and just increasing everything by 2 inches.