well like stated in the title im in a predicament. I have a 1984 V8 4BBL Carb engine, i have been trying to figure out of it is a H.O. engine. When I put my VIN in the thirdgen VIN decoder it comes up as an LG4, but when I put my VIN in the free carfaqs report it comes up as a 4 bbl OHV..

now, someone told me that if the eigth digit in the VIN is a G, then I have an LG4, but if the digit is an H then I have a L69, the eight digit in my VIN is an H, please help me shed some light on my tricky situation, man I hope I have an L69....



oh and to kill 2 birds with one stone, I have an automatic, say I wanted to race my auto manual shifting "1, 2, D, etc." if I took off how many RPM's should I power brake without peeling out, so I get a strong take off, when should I shift to second? "right before it redlines like in video games?" if I did that would it chirp the tires when I shifted to second??? what are the best time to shift? "what rpm's.



thanks guys this means alote

 

do u have two hoses coming out from your aircleaner?

i think all the l69 motors got the 3.73 rearend gears...

so if around 3k at 50 in 3rd that could be a sign also that u have a l69




:lala:

 

H is the digit for LG4, G is for L69.

OHV = OverHead Valve

https://www.thirdgen.org/newdesign/tech/techdb.shtml look about a third of the way down

AFAIK there is no such thing in 87 as a L69 in a F-body, only in Monte Carlo SS

1. Depends on your tires and alot of other things; experiment and find the best results; usually these cars will take that motor with the TC fully stalled because there's not enough torque from that motor to break any kind of decent tires loose, especially not with the 2.73 gears they usually have

2. Try 4400 1st to 2nd, 4000 all other shifts; generally you want to shift at max HP RPM, and hope that the RPM in the next gear is near the max torque RPM; except that 1st gear is so deep that the RPM drop is too great for that rule of thumb to work, so you have to wind it in 1st past where its pull starts to decline steeply for; see link above for the RPMs in question

 

your torque converter is more than likely set at 1500. i rev to 1400 when im staging...anything more and A)i'll spin and/or B) i'll breka the light and foul out. i shift right at 5K, you lose a little top end but it puts you in PERFECTLY where you want to be in 2nd and third gear.

 

thanks a grip guys, i figured out t was a LG4 , but heyi dont mind having 20 extra hp and having 80-100 extra foot pounds of tork compared to my old six , i gotta try that shifting thing today

 

What you will like even more is how well an LG4 responds to mods! They are completely hobbled from the factory, so virtually anything you do to it will be very noticeable. Put on headers, intake, cam, port and polish the current heads and you won't recognise the car. You'll be cutting quarter mile times in the 14s. No kidding.

 

I think it would be foolish to shift any higher than 4000 rpms with an LG4. Doesn't that cam stop making power around 3500 rpms. Just shift right when you feel like the car isn't pulling as hard.

 

The party stops around 4200-4400 rpm with an LG4. I used to have an LG4 formula and i shifted around 4500...after that it sounds like its about to fall apart. A few times i wasn't paying attention when i was swinging donuts (HS memories...)and had it going 5000+ but it didn't hurt it.

 

i must have one tough Lg4, it pulls right on up to 5k, but anything more then that and it gets iffy to say the least. As far as staging, if i rev my motor anything higher then 1500, and then it looks like im powerbreaking with the tires screeching. But yeah, everyone makes these motors out to be dogs but they arent that at all. Once i get gears and a trans go shift kit im sure to see 14's.