2nd generation?
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2nd generation?
I am playing around with an 87 LT firebird I am told that the engine is a 2nd generation engine is there such a thing? and what can I do to up grade it. I already installed accel plugs, wires, distributer cap and ignition coil as wel as an msd6al. I have been told that that an Elderbrock intake won't fit and it looks like headers will be a tight fit. Finally does that model have a chip that I can up grade
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Joined: Jul 1999
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From: Loveland, OH, US
Car: 4
Engine: 6
Transmission: 5
If the engine is a small block Chevrolet, then there is an Edlebrock intake that will fit it. I'd say that the odds are probably greater than 99,999 to 1 that your car has that kind of engine.
Yes there is a 2nd generation of these cars; it ran from 70½ to 81.
Chances are, if it's a different motor at all, it's a 305 or 350 from a 70s or early 80s Camaro. The intake would be slightly different (emphasis on slightly) from the one for a 87 engine, but that's not the same as saying it won't fit.
Headers are a tight fit in one of these cars.
Get a casting number off the block, and casting numbers off the heads, and tell us what kind of induction it has, maybe we can point you in the right direction.
Yes there is a 2nd generation of these cars; it ran from 70½ to 81.
Chances are, if it's a different motor at all, it's a 305 or 350 from a 70s or early 80s Camaro. The intake would be slightly different (emphasis on slightly) from the one for a 87 engine, but that's not the same as saying it won't fit.
Headers are a tight fit in one of these cars.
Get a casting number off the block, and casting numbers off the heads, and tell us what kind of induction it has, maybe we can point you in the right direction.
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I talked to my mechanic and he believes that the casting number is at the back of the engine. He said that sort of pulling the engine it would be difficult to see the number. I apologize for my ignorence but this is my first time working on a car so I obviously don't know a hole lot. I decoded the VIN the other night and it said that the engine is a LG4 I don't think that the engine is after market because it looks like all of the emission parts are still there, can I remove them? any answers or seggestions would help, thank you
Supreme Member
Joined: Jul 1999
Posts: 18,457
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From: Loveland, OH, US
Car: 4
Engine: 6
Transmission: 5
OK...
The question about what to do to the LG4 to help it out gets asked every few days. If you do a search on it, you'll find lots and lots of suggestions.
The first thing about it that's weak is the exhaust. Every piece all the way from the heads to the streets needs to be replaced, all at once, as a unit; with the exhaust for some other engine. No part that fits any LG4 part will improve much of anything, that's why it all has to go. Get application-specific headers for some other car such as a 350 TPI car, and the cat and a cat-back for the same application. Repeat, do not get any part that will fit LG4, because if you do, you will be retaining its primary malfunction, which is the small Y-pipe size.
By itself, the exhaust will do very little to the car; but without opening it up, nothing else will do anything either.
Next issue is the cam. That engine along with the TBI 305 that replaced it in 88 is victimized with the most anti-performance cam that Chevrolet has ever put in a small block. Something with about 210° of intake .050" duration and 220° on the exhaust side, with as much lift as conveniently possible, works the best in that motor with an auto trans and stock converter and the rear end gearing that combo got. The 87 should have a roller cam.
Again, changing the cam by itself will do almost nothing, because the exhaust chokes the engine so bad. Exhaust and cam together will wake it up astonishingly; probably 50 HP at least, maybe more.
Next is the heads. A 87 should have the 081 casting, which is an OK casting, one of the better 305 castings (not saying much). You can port them, and get another 20-25 HP out of that if done perfectly. 15 HP or so is probably more realistic for a DIY port job.
After all that, you might want an intake. Until you repair those other things, the intake is entirely adequate, and buying one would be mostly a waste of money.
Just yanking the emissions stuff off of it won't accomplish much, and will just get you in trouble if you don't know what you're doing. It doesn't cost near as much power as the rest of the stuff I mentioned. My 83 has a set of Edelbrock headers, a different cam, and a set of high-flowing heads; the block, carb, intake, air cleaner, cat, exhaust, and cooling system are all stock; and the engine produces about 260 HP as measured on the chassis dyno and corrected for drive train losses. All emissions devices are installed and operating, since the car was registered in California until recently, and they check for the presence of every single emissions related piece.
Resist the temptation to just unbolt and swap stuff on top of the motor that's easy to get to and highly visible and sexy-looking. That is not the way to make it faster. The real deficiencies of the motor are in places you can't see. The way to make a car (not just an engine) faster is to identify the most limiting factor, and target it for improvement; then identify the next limit, and improve it; and so on. If you simply start replacing parts because you can, you'll waste a bunch of time and money, and you won't improve the car's performance by very much at all.
The question about what to do to the LG4 to help it out gets asked every few days. If you do a search on it, you'll find lots and lots of suggestions.
The first thing about it that's weak is the exhaust. Every piece all the way from the heads to the streets needs to be replaced, all at once, as a unit; with the exhaust for some other engine. No part that fits any LG4 part will improve much of anything, that's why it all has to go. Get application-specific headers for some other car such as a 350 TPI car, and the cat and a cat-back for the same application. Repeat, do not get any part that will fit LG4, because if you do, you will be retaining its primary malfunction, which is the small Y-pipe size.
By itself, the exhaust will do very little to the car; but without opening it up, nothing else will do anything either.
Next issue is the cam. That engine along with the TBI 305 that replaced it in 88 is victimized with the most anti-performance cam that Chevrolet has ever put in a small block. Something with about 210° of intake .050" duration and 220° on the exhaust side, with as much lift as conveniently possible, works the best in that motor with an auto trans and stock converter and the rear end gearing that combo got. The 87 should have a roller cam.
Again, changing the cam by itself will do almost nothing, because the exhaust chokes the engine so bad. Exhaust and cam together will wake it up astonishingly; probably 50 HP at least, maybe more.
Next is the heads. A 87 should have the 081 casting, which is an OK casting, one of the better 305 castings (not saying much). You can port them, and get another 20-25 HP out of that if done perfectly. 15 HP or so is probably more realistic for a DIY port job.
After all that, you might want an intake. Until you repair those other things, the intake is entirely adequate, and buying one would be mostly a waste of money.
Just yanking the emissions stuff off of it won't accomplish much, and will just get you in trouble if you don't know what you're doing. It doesn't cost near as much power as the rest of the stuff I mentioned. My 83 has a set of Edelbrock headers, a different cam, and a set of high-flowing heads; the block, carb, intake, air cleaner, cat, exhaust, and cooling system are all stock; and the engine produces about 260 HP as measured on the chassis dyno and corrected for drive train losses. All emissions devices are installed and operating, since the car was registered in California until recently, and they check for the presence of every single emissions related piece.
Resist the temptation to just unbolt and swap stuff on top of the motor that's easy to get to and highly visible and sexy-looking. That is not the way to make it faster. The real deficiencies of the motor are in places you can't see. The way to make a car (not just an engine) faster is to identify the most limiting factor, and target it for improvement; then identify the next limit, and improve it; and so on. If you simply start replacing parts because you can, you'll waste a bunch of time and money, and you won't improve the car's performance by very much at all.
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