forsete

I’m a life-long computer nerd, who recently took a 180 deg. turn and fell in love with 3rd Gen F-bodies. I have a pretty sweet, relatively beefy, rebuilt (less than 20,000 miles) 305 engine in my ’87 Trans Am, but I’m getting hungry for something more. I’ve seen many different figures out there but I guess it’s putting out 150-170hp.
I’m aware of the conversion kit that is currently available from GM dealers, but a $4,000.00 to 4,500.00 engine upgrade seems kinda pricey for a $2000 daily driver car.

Are there any other options out there? If I haven’t been misinformed, the 305 is virtually the same block as a 350, right? (Just de-bored?). So can you somehow rebuild it to a 350? (Keep the core?)(Sounds too good to be true, so I’m assuming it is.) Or can you get an old 350 from a retired F-Body and just swap ‘em? One last question: Will I need to replace my 700R4 tranny, rear-end, drive shaft, chip, fuel pump, and what not, or can my stock 305 gadgets handle/supply the extra hp and torque?

Thanx for any replies

nestz28

iTrader: (1)

Hey- no, you can't turn your existing block into a 350, you can get a stroker kit to turn it into a 335(?) but it would be cheaper just to buy a complete 350. I am doing the same swap this summer and I think I am going to buy the new engine from performance automotive warehouse (www.pawinc.com) You can definitely get get a new or remanufactured 350 for less than $4000, maybe more like $2000 if you just want a basic mild 350. Try looking into the new GM Goodwrench engines, they are pretty reasonably priced. You can just swap the engine itself and keep the stock computer, fuel injection, exhaust, etc.. but you might want to consider getting headers and a new chip to make the most of your new engine because the 305 components will most likely not be good enough. If you have TBI a larger throttle body would definitely be a consideration too. If you don't have the money to spend on all of this stuff right away you can just swap the engine itself and upgrade everything else later. Hope this helps.

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'84 Z28 LG4 T-5
'92 Z28 wheels
153,000 miles
Front& rear suspension rebuild using MOOG parts
350 and WC coming in summer 2001
'70 nova 307, th350, all stock, 40,000 mi almost like new

nestz28

iTrader: (1)

Hey- no, you can't turn your existing block into a 350, you can get a stroker kit to turn it into a 335(?) but it would be cheaper just to buy a complete 350. I am doing the same swap this summer and I think I am going to buy the new engine from performance automotive warehouse (www.pawinc.com) You can definitely get get a new or remanufactured 350 for less than $4000, maybe more like $2000 if you just want a basic mild 350. Try looking into the new GM Goodwrench engines, they are pretty reasonably priced. You can just swap the engine itself and keep the stock computer, fuel injection, exhaust, etc.. but you might want to consider getting headers and a new chip to make the most of your new engine because the 305 components will most likely not be good enough. If you have TBI a larger throttle body would definitely be a consideration too. If you don't have the money to spend on all of this stuff right away you can just swap the engine itself and upgrade everything else later. Hope this helps. BTW, your tranny and rearend should be fine unless you go above maybe 300hp.

------------------
'84 Z28 LG4 T-5
'92 Z28 wheels
153,000 miles
Front& rear suspension rebuild using MOOG parts
350 and WC coming in summer 2001
'70 nova 307, th350, all stock, 40,000 mi almost like new

nestz28

iTrader: (1)

All of your stock stuff will work ok if you just switch from a 305 to a 350, but things like exhaust, chip, and the stock TBI (I am assuming that's what you have) will not let the 350 operate at its full potential. You can always upgrade those things later if you don't have the cash right now, you will still feel a significant increase in the meantime. Your tranny and rearend should be just fine unless you go above about 300hp. You can definitely get a new or rebuilt 350 for less than $4000. Try looking into the GM goodwrench engines or try PAW (www.pawinc.com) You should be able to get a decent 350 in the $2000-2500 range. Hope this helps.

------------------
'84 Z28 LG4 T-5
'92 Z28 wheels
153,000 miles
Front& rear suspension rebuild using MOOG parts
350 and WC coming in summer 2001
'70 nova 307, th350, all stock, 40,000 mi almost like new

nestz28

iTrader: (1)

Whoops sorry about all the posts, I kept getting a url not found after hitting the submit button so I thought it wasn't working.

five7kid

iTrader: (14)

I'll admit that it's been over 6 years since I lived in California, but last I heard the Smog ***** weren't using thumb screws to determine the displacement of your engine.

A 350 will go in place of your 305 and still look like a 305. Keep things like the cam from being too wild, use CARB-approved headers. Assuming you have TBI, get a larger TB to help feed it. Shouldn't have to look for a hiding place when smog test time comes around.

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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R. 2.93 limited slip. Cat-back from '91 GTA, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 w/LB9 block, ZZ3 cam and intake, TBD heads ported & polished, Hooker headers & y-pipe, 3" Catco cat).
57 Bel Air, my 1st car. 0.030 over 396, Weiand Action+, Edelbrock 1901 Q-Jet, Jacobs Omnipack, 1-3/4" headers, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Best 15.1 @ 5800' Bandimere. Daily driver while Camaro was being put together.

Engineboy

As five7kid stated, just run the 350 in place of the 305 and buy parts that retain all working smog components and no-one will know its a 350.

Us "smog *****" don't usually look that hard.

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ASE Mechanic/Machinist/Smog Tech

1999 NBM Trans Am
1986 Chevy 3/4 ton pick up
1981 corvette
1995 Kawi ZX6R

R.I.P. #3
My favorite quote about D.E. "He can see air"

camaroguy99

won't a 350 make more CO and what not then a 305? I would think they would have different standards for the 2 cars. Besides you can do an engine swap legaly in cali. after you finish all you have to do is take it to a referee station and tell them you swaped out the engine. They will perform all the tests on it and then give you a plate to put on the car telling everyone else that there is a 350 in the car and to test it as such. This only holds true as long as you are going to keep all the emisions stuff on there.

forsete

Yeah, my main concern was the increase in CO (and what not), and the sniffer reacting to that. As for the smog guys visually being able to see if it’s a 305 or 350 I’m not too concerned about. I was planning on a fairly mild 350 (or at least in it’s appearance).

Thanks for all the info guys…

Dennis_91GTA

Here's an idea. How about selling your car to get your $2 grand back and then putting another $2-3 grand with that to get a newer 90-92 TPI Trans Am or Iroc? You would have a much better base for your future mods (5.7, TPI, alum driveshaft, 4 wheel disks, the right computer, a stronger tranny, serpentine belts, etc.). Of course if you really love the car you have, then this wouldn't make sense for you.

Just a thought...

five7kid

iTrader: (14)

A fresh cat will keep CO levels down to acceptable levels, assuming all other things (like tune) are in good shape.

AT4 T/A

This isn't exactly accurate. I had one of my buddies swap a 350 in place of the stock 305 in his '86 T/A. He tried to get the ref's approval only to learn that he didn't have a California certified block. The ref said that even though the 350 block came out of an '87 Camaro, the donor car was registered in Nevada. The ref refused to pass the car. My buddy did put all the correct smog stuff on, and only a couple of aftermarket CARB approved components in. He got so pissed he just got a P.O. box in Vegas and registered the car there!

camaroguy99

really? Thats scary. I have never heard of a specific block being legal/not legal. I am in the process of my own swap. I guess I better just cross my fingers.

Onr other benifit of doing a swap over puchasing an IROC, insurance. They think you have an RS so they don't put a sport car surcharge on your insurance. (at least in my area) Which can be pretty expensive when your 20 years old with a couple of speeding tickets . This way you get the best of both worlds.

[This message has been edited by camaroguy99 (edited March 29, 2001).]