NOS is a snap with EFI, but I was thumbing through my Summit catalog and found a few NOS kits thats availible for the q-jet's. They have one thats set to 125HP and one thats adjustable to 100-150HP. My questions are these kits setup to be used with a stock q-jet, my guess would be no, and what modificatins are needed to run NOS?

 

Apart from perhaps taking a couple of degrees of timing out, I can't think what else you'd want to do to use nitrous.

 

Would work just like a standard carb since almost every computer vehicle I can think of goes into open loop at WOT.

IIRC the LG4 and L69 both use a knock sensor so retarding the timing more than 2* may not be necessary.

 

Thanks, I may just buy it and find out. I took the T/A out today and gave it it's first long trip around town since I rebuilt the engine and everything works woderfull, so I will drive it for a month or so before stuffing NOS in it. It's not a daily driver.

 

LG4s did not get a knock sensor until I think 1985. 82's and 83's did not get them i know.

 

That's my understanding, knock sensor for LG4 in '85 when the compression was raised.

What I wasn't clear about was whether the knock sensor is active in open loop.

 

My 1983 had one but maybe the cars didn't get one. I know the trucks with the CCC carb had them.

 

My 1984 LG4 doesn't have one, but my 1985 LG4 did.

It makes no difference when it comes to nitrous (having a knock sensor), because typically nitrous melts pistons, not hammering them with detonation. Either that or you throw rods out the block.

Do buy an adjustable nitrous kit for any car - its more adaptable. Do upgrade your fuel system - a stock block pump is not going to be able to keep up with a 125hp nitrous kit, so either go electric (near the tank), or get a high volume block pump and regulate it.

Rule of thumb for timing is 2 degrees for every 50hp of nitrous. Since stock LG4 timing is so low (ECM does this on purpose), you probably only want to retard it 2 or 3 degrees with a 125hp kit.

 

By the time it knocks once it's already too late.

 

Mines is an L69 and I used a bigger cam when I rebuilt it and I plan to use a high volume block pump and a regulator like you said. Thanks for the tip on the timing retard, I'm running 16* over the cams recommended 14* right now.

 

I know this post is almost a week old, but I had to reply.

Back in 1990 I bought a mint 1984 Caprice 2 door that had the LG-4. I installed dual exhaust, a shift kit, posi, and then topped it off with a "Super Power Shot" from N.O.S. They still make this kit. It worked very well on the basically stock LG-4.

Just make sure your fuel pump puts out at least 6 psi @ 60 - 80 gpm.

It comes with jets for 75, 100, 125 hp, and you can order the jets for 150, and 175 hp. I threw the 125s in it and never looked back.

Later on, I traded it and the edelbrock fuel pump I bought, for a case of beer.

I quit drinking since then.