So who here has the fastest LG4? obviously not me....with a 16.5 @84.....with a 2.3 60ft........so who here has the fastest?

 

Before I swapped in my 383 I had my LG4 down to a 13.4 1/4 mile but of course it had a lot of mods. The bottom end of the motor was all stock with about 100k miles on it. I was using ported stock heads that were milled .030 and had the bowls blended. Combo: Crane 274H cam, RPM intake, vac advance HEI w/ recurve kit, hedman LT headers, 600cfm edelbrock carb, 4.10 gears, B&M 700R-4, 3000 stall, ET street tires. It was a good cheap street/strip combo that was fun to drive until I got out of college and saved up money for the 383.

 

You certainly are going to have to better define what you mean by "LG4". As left by the factory, they're all going to be pretty poor. The air cleaner and exhaust are horribly restrictive, so anything that leaves them in place will probably remain slow.

If all you require is the LG4 controls, then you can have a pretty quick runner. The factory HO 350 conversion put a ZZ4 crate engine under the factory emissions-legal controls, with tuning, but exhaust & air cleaner were also replaced with some good stuff. That produced 13's.

The best I did before the mods in the sig was 16.8 at 5800' elevation (equates to mid-15's at sea level). Even then I had an open element air cleaner and L98 cat-back on it.

Now, I've basically got the HO 350 conversion without the 350. When the transmission is fixed, and real gears are installed, this car will run a lot quicker than it has so far.

Is it still an LG4, though?

 

my 100% stock LG4 went 16.0 at 85mph w a 2.3 60ft. the car had 95k on the clock, and has an auto trans mated to an open diff sporting 3.23 gears

i recently did a full tune up, flushed all the fluids, and performed a few free mods. i also replaced the air cleaner assembly with a open element filter, and swapped out the restrictive catback for a dynomax one. havent been to the track to test the new combo due to the water pump blowing up. i think it would run mid 15s with a decent launch

 

Here's my best time so far, 2.19 60' running 15.21 @ 90.18 mph. I'm sure if I were to go to the track this month I could break into the 14's with the cooler weather. Not sure if I'll be able to go to the track though

 

with only headers and cat back i'm runnin 15.8. but not for long 350 coming soon

 

im hoping for low 15's this saturday, ill have my slicks and hopefully my lower control arms on for that day. im not goin to jinx myself as to saywhat ill run but im just hoping for low 15's if im lucky. and my mods are in the sig, my best run to date was a 16.003 at 83 mph with a 2.3 60' time, my newest runs have been 16.5 and 16.3 at 84 -85 mph with 2.4-2.5 60' times.

im goin to try to get them 60's down to like 2.0 maybe 1.9 this weekend. i just hope traction will be on my side this weekend and no rain. Saturday is suposed to be 65* partly cloudy, no rain but 20% chance of precip. hopfully it will turn out nice.

 

With that kind of mph it'll be a bit of a stretch to hit low 15's I would think :/ My mph ranged from 89 to 90 and times were 15.80 to 15.21. Biggest factor was traction hehe worst 60' was 2.68 and got it down to the 2.19 on my best run.

 

I have the fastest 305. Its the fastest NA Fuel INjected 305 around town. 5 speed
Its been Vtected at haveing 470 horse. Not this thing needs more tuning.
Will go to the trac and run on STOCK radials. No drag tires hear!
And I will crush those times.

Its a stock bottom end, stock cam, I have vortex heads. And a vortex truck (Ram Jet Styled) intake. With 24 lb injectors and a ls1 style throttle body. 1/58 headers.

The most important mod is I have 2 true 3 inch exhaust side pipes with flowmasters. This is the point where I get alot more power then you guys. Its the bigger the exhaust pipe the more power you have.
Shane I will race you for pinks if you are a NA 305 and in IL I could use another 3rd gen!LOL
Shane

 

He didn't say "fastest 305", he said "fastest LG4". Fuel injection automatically disqualifies you here, I'm afraid.

I repeat, how much modifying are you allowed to do and still call it an LG4?

(Vtech HP is magazine mechanic bench racing. Let's see some dyno sheets or time slips. Dual 3" exhaust on a 305? Yup, that must be where you've got us - we never thought of that for some reason...)

 

i think weve got a r i c e r with a 3rdgen here

if IL wasnt so far from me, id race you for slips... i need a T/A for parts

 

I dont think so. In fact. you are probably losing some TQ with a set up like that.

Some of the 305's around here are running better than my 350. Its time to start buying some parts. Maybe I'll put in a true dual 8in. exhaust and be making about 1000 ponies. J/K

 

But only if you have a "Type R" sticker on the windshield, too...

Having an LG4 that's faster than some 350's is kind of like the preacher who pretended to be sick on Sunday so he could play golf, and got a hole-in-one. It's a great feeling, but you're the only one who knows about it.

 

First I was confused by Vtected 305 then I read the bigger pipes the better and I thought O its him not me.

 

I've hit 14.494 seconds and 98.69 mph with mine in the SC (when it was alive ). This was in street-driven condition with 3/4 tank of 87, and the sub box in place.
It had about 225,000 miles on the clock; the original heads have never been off the engine. An 84 vintage - low-compression - it has a small 0.420" lift cam, and Hedman shorty headers, y-pipe and a Dynomax 2 3/4" catback. A T5 and a 3.42 open rear give me 2.3x 60' times. Stock cast iron intake, the original Q-jet has a set of DR secondary rods and an N hanger.
Can't wait to see how it will run in my Formula with it's stiffer chassis

Pete

 

All I have is an edelbrock cam (2102), open element, TES headers and y-pipe, dynomax cat, dynomax catback, stock 2.73 now open and my best run was 16.45 @82 mph. That was before I knew my cam could hit 6,000rpms and like it though. So it was shifting at factory 4500rpms when its max power is 5500. I think I can drop at least a tenth by shifting higher.

~Matt

 

i have an 87 LG4 in a heavy g body all stock with cheap true duals with cats and turbo muffs. Open element air cleaner and a qjet off a 79 350. 3.73 gears. I ran a 16.4@85mph 2.5 60 ft, 10.5 in the 1/8th
later on got it running better and spun really bad and ran a 16.6 @87 mph 2.7 60ft cant remember the 1/8th mile i think it was 10.8.
it seems like i'm running a lot better trap speeds then people running low 16's so maybe if i get traction i could hit 15's? Gonna get headers and maybe a performer intake for xmas how much do you think this will help?

 

Yea, I ran 16.45 at 82. 87 mph is good for mid 15s I believe. Also, your 60' is really bad. 2.5sec with 3.73s? Did you spin on that run too? I had a better 60' with 2.73s and my drivetrain isn't even matched. Are you stalling the car and launching it?

~Matt

 

Well i dont think i'm stalling it up enough, if i remember right it was breaking the tires loose at about 1300rpm. Maybe i wasn't holding the brakes hard enough?

When i had the 2.5 60ft it was squealing but basically hooked up really good. When i ran the 16.6 @87 it basically did one of those showoff burnouts where you just try and spin the tires and go nowhere for a few seconds, it went into second gear before it finished spinning.

I hope your right about the mid 15's. Maybe i could get low 15's with headers and performer intake.

 

Back in the day, my 99% stock LG4 (only an open element air cleaner) ran 16.04 @ 85 with a 2.45 60 foot.

The car had 3.23 gears (open) and an auto with about 110,000 miles. Weghed in at 3700 w/ driver.

 

Nice Trevor. Some engines get more power than their twins To launch the Cutlass, go with all brake, and about half gas. That should get you to stall speed. I don't know exactly what your stall is, but it is probably between 1500 and 1900rpms. If the tires start spinning, then give it less gas, since you already have full brake. Just launch it right, because your tires are saying 15s and your car isn't actually making it down there that fast :lala:

~Matt

 

Oh yea Trevor, I just saw your post again. Your 60' was worse than mine, but you ran a good time. Also, Canadian LG4s in 86 didn't get ECMs. I want mine out. What do you have in there now that runs the time in your sig?

~Matt

 

!305

in with a 350.

With a performer intake (not an RPM...gotta match the LG4 powerband), and maybe 1 1/2 or 1 5/8 headers and a dump, and traction (coulda shaved off 2 or 3 tenths with my ET streets that I have know), I think it woulda been in the 15.5 range. Which is low 15s at sea level.

 

Well Anymethod, you were right. I got my car down to 15.5. Throughout the night I was getting faster each time. I made 12 passes. It was the first night out so there wasn't much of a crowd. Almost no lineup. I let the car cool off after 2 runs each time cause it runs better at around 165degrees and we had a long return drive along the autocross track.

Got my launching down pretty good, doing a big burnout each time to warm the tires. Got her to stall a bit higher, holding the brakes real hard. And manually shifted through each gear. Went through the traps at about 5000rpm in 3rd gear.

MPH wasn't recorded in the left lane, but one of my earlier passes where traction was still bad (before I dropped my tire pressure down to 20psi) I ran a 16.4 at 87.56mph so I'm thinking my 15.5 must have been at least 88mph.

Also I was running no air cleaner and 94 octane with timing advanced a bit by ear. Also had almost no gas in the car. Arrived at the track with less than 1/16th of a tank (Gotta love the gas mileage of the LG4) and my last pass I was getting very low on fuel. It was also pretty cool out as the night went on, so I'm pretty sure there isn't much more left in the LG4, except maybe 1 tenth or 2 as I still spun a little bit.

I'd have to dig out my timeslip to get the 60ft and 1/8th miles on that run but I do remember last time I went out I only ran a best of 15.8 @87.9x (not as cold out and I had more gas in the tank), but I was running better off the line. Getting lots of wheelhop but felt like better traction than before and I ran a 2.1 60ft and an 10.1 1/8th mile (previous best was like 10.3 I think).

 

My basically stock LG4 runs consistant 15.5 at 90-93 mph. I have a 3in cat back (no cat though) and an Edelbrock carb and open element. The motor is completely stock with 95k on it.

 

I think the LG4 should have to have the stock block heads cam and compression. The carb /computer can be tuned and the intake can be changed along with the air cleaner. The main focus should be on aftermarket exhaust and gearing and tranny w/DR's.

I think a LG4 with a good intake manifold, air cleaner, longtubes into 3inch cat back with cutout before the cat, WC T-5 with clutch and 3.73's and DR's would run tight,into the low 14's. Don't forget some Aluminum Roller rockers and weight reduction.

 

That MPH is astounding! In fact, its unbelievable! Unless you're talking about a GTech time...

 

Hey Marc, let me try to scan my timeslips in. Sorry it took so long.

 

Here you go.