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Discussion Starter #1
what are some cheap basic performance mods i can do on my 92 caprice classic with a 305smallblock?
 

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Stock LT1 Cam & New Springs - Headers - Throttle Body Mod - AFPR - area few good starts, along with getting a new chip "burnt"
 

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"Ultimate TBI" mods:
http://www.thirdgen.org/ultimatetbi2
Don't forget the "quarter mod" if you get your intake/exhaust work finished.
Here's a pic:


Cold air intake,
Lots of other ways to do cold-air intakes.
Here is the "Caddy" intake setup on my old TBI car:



Get some stock dual-exhaust pipes from a LT1 ('94-'96) B-car and replace the mufflers with ones of your choice. Many people have these laying around that they'll never use. You will need to get the transmission crossmember modified to accept the other exhaust side. You can also upgrade the stock single exhaust also, without modifying the transmission crossmember.

Stock LT1 exhaust manifolds flow better than stock L03/L05 exhaust manifolds and will bolt up, if you can get the "y" pipe modified to fit.

If you don't need smog requirements, you can always gut the cat(s)

Delete the air pump and re-route the belt. Unlike LT1 cars, the air pump on the L03/L05 is belt-driven. If it's removed you can use an alternate belt routing.

As mentioned, upgrading to electric fans can free up some HP too, and can also really clean up the engine bay and allow easy access around the front areas.

Stock LT1 cam can be had for next to nothing, and makes a good performance cam (without getting too crazy) for TBI cars.

Lots of other options but you start to leave the free/cheap area.
 

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If you put a 350 in it you will get 180 HP and 300 lb.ft. of torque. If you put a 350 from a 91-93 9C1, you get 205 HP. Used ones are about $350 at the pic-n-pull junk yards. They bolt in, but you need the computer for about another $50. The 9C1 has a similar cam to the LT1. Larger 9C1 Y pipe, and exhaust system (you can get the cam, injectors, computer, and exhaust for your 350 to make it a 9C1 350).

Put an extra gasket under the injector holder on the TBI to open the intake path.

3.23 gears will make it feel like it has more power, and will not affect your gas mileage. The gears in the VSS will have to be changed to match the gear ratio/tire size.

If you are going to install a cold air intake, move the charcoal canister under the wheelhouse with the bracket from a 94-96 (found on the opposite side).

The dual fans from a 93 FW are a perfect fit, and you only have to figure out how to turn them on. Temp sensor with switch, and AC clutch...have them run by relays. Electric fans will give you about 5 HP.

From here on, you are going to have to get the computer chip burned.

You can use the larger TBI from a 454, and the injectors from a 9C1. You will have to bore the intake out so there is no lip where the TB and the manifold meet. You also have to get the larger gasket set, or open the holes on a set for the smaller TBI. The connector for the cruise control is larger on the larger TBI, and you will have to ream the end of the cable as well as a larger clip. Adjustable fuel pressure regulator, and fuel lines from a LO3/5 equipped 91, 92 or 93 FW with Schrader valve for a fuel pressure gauge installation.

Cam of your choice, springs, rockers, etc.

Headers (about 20 HP), duals, and modified trans crossmember/redesigned crossmember for duals.

Reasonable expense for another uprade is a 350/5.7 Vortec engine from a later truck with its wiring harness, computer, and possibly the transmission. You will have some wiring adaptation, and maybe the FEAD, or use the one from the LO3 if the bolt holes match. You might need a stronger fuel pump, and a reprogram for the computer. Cam, headers, valve springs, duals, trans crossmember mod, are all doable with a Vortec engine as well. The engine should be the same price as a 9C1 at a pic-n-pull yard, just a little more work, because of the different wiring. You can make more HP with less money with a Vortec than you can with an LO3/5.

Next step up is the LS series engines and matching trans.

If you do it yourself, the mods are relatively inexpensive. If you have someone do it for you, it can get expensive fast.
 

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Discussion Starter #8 (Edited)
ive done the caddy intake and im gonna be moving the charcoal canister soon i have to go get the bracket. Im going down to pull a part and getting the 350 from the police package once i get the money. my buddy said when he did the quarter mod on his car he lost alot of power. the electic fans will probably happen when i have the engine out and swapping it. if anyone knows anyone with a 9c1 cluster for a reasonble price let me know please. thanks alot for the advice. im new to the bbodies but im part of INC so alot of guys that can help.
 

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ive done the caddy intake and im gonna be moving the charcoal canister soon i have to go get the bracket. Im going down to pull a part and getting the 350 from the police package once i get the money. my buddy said when he did the quarter mod on his car he lost alot of power. the electic fans will probably happen when i have the engine out and swapping it. if anyone knows anyone with a 9c1 cluster for a reasonble price let me know please. thanks alot for the advice. im new to the bbodies but im part of INC so alot of guys that can help.
The quarter mod should only increase your fuel pressure a little. Maybe 2-4 PSI. Most of the LO3/5s are low on pressure to begin with, so it should only help.

To upgrade your LO5 to the 9C1 spec, you only have to get the cam injectors, computer, and exhaust/install duals...then you need a modded trans crossmember, and a second muffler bracket for the driver's side. A second left bracket bolts to the right side like it was made for it.

If you need a 9C1 cluster, you also need the dash. The Caprice dash has the idiot lights, that cover some of the cluster. There is/was a 9C1 cluster in a car about 35 miles from me. I am headed there on Memorial Day weekend. If you want it, I will get it for you. You are looking at about $50 shipped. If you want it now, the price is $80 shipped.
 

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To upgrade your LO5 to the 9C1 spec, you only have to get the cam injectors, computer, and exhaust/install duals...then you need a modded trans crossmember, and a second muffler bracket for the driver's side. A second left bracket bolts to the right side like it was made for it.
I think he has the civvie 305 per his original post. This would be the norm for a non-9C1 TBI car for '91/'92. '93 350's could be had in non-9C1's via the LTZ package, albeit in a less powerful version.
 

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I did not check the OP since the last post, and forgot he stated 305. If he is going to put a 350 in it, like he said, the mod will work. It is the cheapest mod for increasing HP in an LO5. Should get 205, and if he uses electric fans from a 93 FW, or LT1 he can get another 5 HP. 93 FW fans are easier to install. Headers and duals should get another 20-25 HP, but that costs a bit more.
 

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i have the civilian model 305 caprice classic. i dont have the LTZ
All 305s are basically the same. 160 HP, 250 lb. ft. torque.

Save your money and do it right.

Start with something you can get a good return on your dollar spent. The most bang for the buck is to find a complete LQ4/9 with the computer, FEAD from a truck, including its trans, at a pick and pull yard, and install it in your car. The total do it yourself project should run you about $1200, and about a month's work if you do not mod the engine. The instructions are in the engine swap thread. You do have to have a little (maybe more than a little) common sense, and some knowledge about electrical/electronic systems. You may have to buy a few tools, unless you have them available to you. You can make a few inexpensively if you have some common sense.

Basic engine change to a 350 will cost you as little as $500 and a few day's work. So, expect to spend a minimum of $500 to have any decent gains. It goes up abruptly from there.
 
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