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Anyone ever played with the baby Lt1, GM L99 motor?
Has anyone ever done any messing with the baby 4.3L lt1 motor around here? I am just curious to know how they perform in the cars and if there'd be any reason to swap one in place of a 3.4L or something. -I know it wouldn't be cost effective; it would cost the same to do the lt1 swap, but just for fun... Do they get better gas mileage? i guess with gas topping 3.46 here today I got to thinking that it might be cool to have a firebird/camaro with the reasonable power, the rumble of a tough motor, and the fuel economy of a V6. Not that i would want to ever give up my 383... but hey, I was bored.
Chime in if you've had any experiences with this motor, i'd like to hear about it.
My car actually originally had one of those.
Milage is good if you stay out of the throttle.
One guy on the Impala board runs one in Stock Eliminator trim and manages 12s but realistically the FEW modded L99 b-bodies out there have maybe managed like 15s NA 14s on the bottle.
Part of me wishes I had not scattered the parts of my old motor to the wind like I did. Think it would have been interesting to see what it would do with the current stall, headers, gears then maybe sprayed it to death.
Sounds like you understand bolting it in is EXACTLY like an LT1 every wiring connection and everything.
My current motor wears the old "l99" intake valvecovers some sensors etc..
i wonder... is the L99 4.3L the smallest v8 gm ever made? i don't know that much about older sbc's so i have no clue.
I guess i'm to the point where a lot of other people might be: when you mod your car so much that strange odd-ball things seem cool just because you get bored with your current setup.
I'd drop one in an f-body just to raise eyebrows and to say.. hey, this is pretty much different than almost everyone else.
Actually, the L99 comes out way ahead of the earlier 265 small block. I'm sure that this is true when comparing the L99 head specs, induction potential, and cam specs to those of a '56 Chevy. There is no doubt in my mind that an L99 fully prepped for NHRA Super Stock competition in a 3000 pound car will run close to 10.50. That performance would put it at or very near the top of the qualifying list for any NHRA event in the country. Needless to say, it would not be particularly streetable but it would irritate a lot of guys with big inch, big budget operations.
Actually, the L99 comes out way ahead of the earlier 265 small block. I'm sure that this is true when comparing the L99 head specs, induction potential, and cam specs to those of a '56 Chevy. There is no doubt in my mind that an L99 fully prepped for NHRA Super Stock competition in a 3000 pound car will run close to 10.50. That performance would put it at or very near the top of the qualifying list for any NHRA event in the country. Needless to say, it would not be particularly streetable but it would irritate a lot of guys with big inch, big budget operations.
I'd seriously like to see that! I wonder how well they respond to mods. I mean, i'm sure there's a ton of bottlenecks to open up. Could they be made to breath as well as a properly modded Lt1? It'd be sweet to have a n/a 265 cubed V8 motor making close to 400 Bhp and turning 12's (would need decent 60ft times) -bump the compression, do the heads, cam, all the goodies (bolt-on), gears, etc... i could see it happening.
It would be cool to have say... a '94 t/a with a fully modded L99 and an Ls1 front end conversion, go to the track and walk a Ls1 powered car. They'd think they're pulling up to an equal competitor, and even if the Lt car only wins by a hair, it would still be sweet to pop the hood afterwards in the pits and say, not only did I win, but i won with an Lt style motor and one about a liter and a half smaller than yours! Sure you could argue about the cost-effectiveness of it. You could headers and cam any ls1 powered car and probably walk the most heavily modded L99 car for a fraction of the cost that the L99 car had to spend, but this isn't about cost or time, it's about separating yourself from the pack
....ah, perhaps these are all but pipedreams.
It's also surprising to me that people haven't taken this idea and ran with it. I mean.... look at all the stupid things people like to do with rare setups. Take for instance: Cross fire injection. There is an article in GMHTP this issue about a cross fire car that runs sick 1/4 times. it's just cool to have something different than everyone else.
Actually, a racer from South Dakota has an L99 powered Olds Achieva that currently runs consistently in the 10.80 range and I suspect that the full potential of the combination hasn't yet been reached. It's the only one that I know of in entire country but it proves that the combination can work. He typically qualifies number one at any NHRA meet that he attends.
By way of comparison, a well-built LT1 in an NHRA Stock Eliminator car is easily capable of 10.50s or better and several LS1 Stockers have broken the 10 second barrier and run high 9 second times. On the street, cubic inches will usually be the king and the presence of nitrous and/or boost trumps everything. Mostly in the rather limited world of NHRA, racing for class trophies and bragging rights, does the L99 have a chance to shine.
Actually, a racer from South Dakota has an L99 powered Olds Achieva that currently runs consistently in the 10.80 range and I suspect that the full potential of the combination hasn't yet been reached. It's the only one that I know of in entire country but it proves that the combination can work. He typically qualifies number one at any NHRA meet that he attends.
By way of comparison, a well-built LT1 in an NHRA Stock Eliminator car is easily capable of 10.50s or better and several LS1 Stockers have broken the 10 second barrier and run high 9 second times. On the street, cubic inches will usually be the king and the presence of nitrous and/or boost trumps everything. Mostly in the rather limited world of NHRA, racing for class trophies and bragging rights, does the L99 have a chance to shine.
Someone in N.C. is building one for an F-body to run in stock trim.......they estimate hi 10's........can't say who it is
I have the heads off my old L99 sitting under my toolbox, part of me really would like to bolt them onto something and play, I would have to get the shortblock for free or very close to free to bother though.
I think I know who you are talking about building one for an f-body, believe he already played with it in the pst, do not know what it ran though.
The Stock Eliminator Caprice I mentioned somehow managed the mid 12s shifting at just 5500rpms, I have no idea how he made it go that fast spinning that slow but I know things like a 200 GM tranny which uses VERY little power but an efficient drivetrain is not enough to explain it.
dwayne you know who it is...he knows his LT stuff......I'm pretty sure the last one ran mid or hi 12's but that was in STOCK class...he had to use a stock PCM and it was a little heavier too
i wonder... is the L99 4.3L the smallest v8 gm ever made? i don't know that much about older sbc's so i have no clue.
The last engine I had in my MGB was a 215 cu in (3500 cc) Buick/Olds that was made from 1961-1963 for the Buick Special/F-85. It is a great engine that only weighs 300 lbs fully dressed and put out close to 300 hp with a turbo. The patterns were eventually sold to Rover in the UK and they made v-8's for the Rover cars and actually put one in an MGB for the domestic market.
Re: Anyone ever played with the baby Lt1, GM L99 motor?
I have a baby lt1 in my 97 Camaro. Manuel Trans supercharged,full roller 1.6, ported head's Dual exhaust' Headers, Lightened flywheel, Msd optispark distributor and coil, Crane cams ign control box. This car is a riot to drive.
I actually got screwed when I bought this engine. So I made the best of it. Everything for the lt1 bolted on. Roller rockers were added after the swap so I could get the right shaft size they fit nicely under the stock valve covers.
Very fun to drive i can slip the stage 2 centerforce clutch if I'm not careful. So yes i believe this engine has potential to be more than ppl give it credit for. I've never took it to the drags but around town i enjoy thumping mustang's and them foreign jobbers everyone loves so much. There is alot more work than just the motor but I'm not gonna go into that.
Re: Anyone ever played with the baby Lt1, GM L99 motor?
Looking back at the comments posted to this thread twelve years ago is a fun reminder of how various readers regarded the L99. In August this year (2019) at the U.S. Nationals the #1 qualifier in Super Stock was a 1996 4-door Caprice equipped with the L99 engine. This was his best qualifying run:
1 354 SS/PA Ernie Neal, Columbus IN, '96 Caprice 10.830
That car weighed 3850# including the driver.
Using a time-honored formula for evaluating power:weight ratios (removal of 100# of total weight is worth approximately one-tenth of a second in ET), that specific L99, modified in accordance with Super Stock rules and verified during a supervised teardown, in a 3000# would have been very close to running in the nines!
05-15-2007, 08:47 PM
