305 iroc or 350 iroc?

[rally]

I want a 5 speed car but I want power so what is the best way to go? Can i put in a 350 crate motor into a 305 5 speed iroc? What are the 1/4 mile times between the 350 and 305? And what is the most HP that i can get from a 305 and/or a 350?<br />Thanks

[Ragtop89]

My car was originally a 5-speed/305 combo. Now it's a 5-speed/355 combo. The swap was simple and easy. Now I'm just upgrading stuff little by little.

Stock 305 vs. stock 350?? It would really depend on the type of EFI and the cam. I used to beat stock 350Zs with the old 305 engine - it had beefier cam.

[Autopsy]

hey ragtop...do you have the stock 5 speed transmission or is that a different 5 speed? Im curious about how much that tranny can handle in terms of power.

[Ragtop89]

I've got the original T-5 in there yet. I had to go to an aftermarket clutch because the stock one would slip like crazy. If I got on it I could smell the clutch burning up. I bought a CenterFroce Dual-friction clutch and I haven't had any problems since. I also bought the B&M short-throw shifter. The stock shifter was a pain to speed shift.<br />I'm in the middle of re-re-building my engine and I don't know how long the T-5 will last with the new engine. I've heard that some people have no problems and I've heard that others have had their transmissions go.

I dunno.

[Autopsy]

Of course, some people drive normal, and some people drive like assholes =P

Thanks for the info.

[Jason]

personally, if you have an IROC 5 speed, LEAVE IT. please dont mess up an iroc. if you want a 5 speed with a 350 then buy an RS or even a Z. but please dont mess up an IROC. you will thank me one day when it is worth a shit load of money.

[NBWS6]

I have an 87 IROC that needs an engine. Do you think its wiser too put another 305 in? I'd like it to be worth something one day (its the 1st year convertible). It already wont be the original engine, whats your thoughts on this?

[Dwayne88IROC]

I have 2 IROC's. An 86 305 auto and an 88 305 5 speed(custom ordered from factory). I've thought a long time about what I should or shouldn't do to these IROCS.

This is my thinking.

Save the 305 motor for later and go ahead and have fun with the larger motor. Yes numbers matching IROC's will be worth something some day. NO DOUBT.

Don't cut anything on an IROC.

I wanted to make a very professional looking hole and cover in the floor above the gas tank for easier fuel pump repairs. It's hidden. It's not a chop job. It's going to help the next owner. But it's cutting the original body. Ya won't get much at the Barret/Jackson auctions that way. I'm planning on giving these cars to the kids and not really looking for a TOP $ collector car.

Look at today's resto rods and how folks are paying BIG $ for numbers matching stuff. Save the old stuff.

[NBWS6]

Well, unfortunately the engine is gone, cracked block, so its scrapped. So I suppose I should get any kind to stick in there, whatever I get a deal on. No use in getting another 305?