Should I sell my stang and get a notchback???

Unit 5302 · 08-16-2001, 06:16 PM

I wish I knew where 88workcar went. He was the resident experianced SD guru.

Last I saw he was running Edelbrock 1.94 aluminum heads, Cobra intake, E cam, and low low 12's N/A, should be mid 11's on the juice, with speed density.

I think in the case of SD, it's just even more important that your mods are well matched, and in decent ratio to the stock parts.

Think of it this way. Say you have a 14:1 ratio with SD stock. That's making 225hp. Now you put parts on it to make 300hp. The computer cannot compensate more than about 20%, which is 270hp. So now, with the 300hp parts, you're sitting at 16:1. If you bump your fuel pressure to 50psi from 39psi, now you're back within the computers adjustable specs. It still thinks it's running the stock parts, so it's injecting fuel at a ratio consistant with the air it "thinks" it's getting. In reality, it's getting 35% more air, and about 35% more fuel. That keeps the ratio the same, and the computer within tolerences for compensation.

Obviously, the more matched the parts are in terms of stock parts, the better that will work.

The idea that SD can't take bigger injectors is a frickin joke to me. I've seen a STOCK SD car run fine on 24lb injectors (they were cheaper than the 19lbers a few years back). An MAF car won't even run if you switch to the 24lb injectors without recalibrating the MAF. The SD computer is better able to compensate than the MAF computer. The good thing going for the MAF cars is that they can actually measure air, which makes the computers job way easier.

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08-16-2001, 06:16 PM	#15
Unit 5302 Registered Member Join Date: May 1999 Posts: 5,246	I wish I knew where 88workcar went. He was the resident experianced SD guru. Last I saw he was running Edelbrock 1.94 aluminum heads, Cobra intake, E cam, and low low 12's N/A, should be mid 11's on the juice, with speed density. I think in the case of SD, it's just even more important that your mods are well matched, and in decent ratio to the stock parts. Think of it this way. Say you have a 14:1 ratio with SD stock. That's making 225hp. Now you put parts on it to make 300hp. The computer cannot compensate more than about 20%, which is 270hp. So now, with the 300hp parts, you're sitting at 16:1. If you bump your fuel pressure to 50psi from 39psi, now you're back within the computers adjustable specs. It still thinks it's running the stock parts, so it's injecting fuel at a ratio consistant with the air it "thinks" it's getting. In reality, it's getting 35% more air, and about 35% more fuel. That keeps the ratio the same, and the computer within tolerences for compensation. Obviously, the more matched the parts are in terms of stock parts, the better that will work. The idea that SD can't take bigger injectors is a frickin joke to me. I've seen a STOCK SD car run fine on 24lb injectors (they were cheaper than the 19lbers a few years back). An MAF car won't even run if you switch to the 24lb injectors without recalibrating the MAF. The SD computer is better able to compensate than the MAF computer. The good thing going for the MAF cars is that they can actually measure air, which makes the computers job way easier.