Project L99 Swap Complete
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From: Waco, TX
Project L99 Swap Complete Thought some folks might find this amusing...
I fragged my heads/cam motor in March. I've been trying to figure out what to do about a new LT1 for the car, but my LS1 car is making a huge sucking sound aimed directly at my wallet. So, after letting my car sit for 5 months, I bought a cheap L99 (4.3L baby LT1) motor from Nitro Dave (sponsor -> ). He had it laying around the shop, I picked it up a week ago last Friday.
I put it in my car last week, finally drove my car for the first time yesterday. Not bad. Definitely not powerful, but it's not as bad as you'd think.
I have the 58mm TB, SLP single cat headers, a few other bolt ons, but went back to the stock stall (a Yank ST3500 would be a wee bit much :p ). I also passed on the SVO 30# injectors that I had in there, a set of stock L99 20# will work just fine.
Man, the car is quiet and smooth with a stock bumpstick. And the stock stall is TIGHT. Kinda fun.
I had to roll my own PCM program - taking a 94 Z28 program and intermixing some tables from the L99 (timing and fuel).
The only physical difference is that the L99 has straight plug heads. Otherwise, it's a direct bolt in. I'm using Autolite plugs, which are .2" shorter than NGK's, so I have ample header clearance, even with the straight plug design.
Good to be driving my car again. Now I just gotta hassle with inspection & registration... Funny how those things seem to always slip on my cars.
-Andrew
I fragged my heads/cam motor in March. I've been trying to figure out what to do about a new LT1 for the car, but my LS1 car is making a huge sucking sound aimed directly at my wallet. So, after letting my car sit for 5 months, I bought a cheap L99 (4.3L baby LT1) motor from Nitro Dave (sponsor -> ). He had it laying around the shop, I picked it up a week ago last Friday.
I put it in my car last week, finally drove my car for the first time yesterday. Not bad. Definitely not powerful, but it's not as bad as you'd think.
I have the 58mm TB, SLP single cat headers, a few other bolt ons, but went back to the stock stall (a Yank ST3500 would be a wee bit much :p ). I also passed on the SVO 30# injectors that I had in there, a set of stock L99 20# will work just fine.Man, the car is quiet and smooth with a stock bumpstick. And the stock stall is TIGHT. Kinda fun.
I had to roll my own PCM program - taking a 94 Z28 program and intermixing some tables from the L99 (timing and fuel).
The only physical difference is that the L99 has straight plug heads. Otherwise, it's a direct bolt in. I'm using Autolite plugs, which are .2" shorter than NGK's, so I have ample header clearance, even with the straight plug design.
Good to be driving my car again. Now I just gotta hassle with inspection & registration... Funny how those things seem to always slip on my cars.
-Andrew
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From: Texas, it's like your state, but better.
Re: Project L99 Swap Complete and now for the nitrous 
sounds grand Andrew, i cant say i blame ya considering the horrific price tags on aftermarket LS1 junk. what ever happened to the days of figure it out yourself, and then extort money out of everyone else? oh wait a minute..
sounds grand Andrew, i cant say i blame ya considering the horrific price tags on aftermarket LS1 junk. what ever happened to the days of figure it out yourself, and then extort money out of everyone else? oh wait a minute..
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From: Waco, TX
Re: Project L99 Swap Complete Yeah, this motor is just BEGGING to go out with a boom. 
Wonder if Nitro Dave would let me borrow a DP kit for one trip to the track...
I'm planning on building a 383 LT1, but the '98Z is getting a rollbar, new seats, 5-point restraint, new wheel studs, and likely a trailer to ride on, all in the next few months. So the 383 will have to wait...
Top down is niiice. And once I get the A/C fixed (hopefully later this week), I won't blink an eye to daily drive the 94Z for a while. It'll get better gas mileage than the Suburban. :p
Andrew
Wonder if Nitro Dave would let me borrow a DP kit for one trip to the track... I'm planning on building a 383 LT1, but the '98Z is getting a rollbar, new seats, 5-point restraint, new wheel studs, and likely a trailer to ride on, all in the next few months. So the 383 will have to wait...
Top down is niiice.
And once I get the A/C fixed (hopefully later this week), I won't blink an eye to daily drive the 94Z for a while. It'll get better gas mileage than the Suburban. :pAndrew
