im planning on swapping out my old slow 305 with a fresh 383. and swapping the rearend with a disc brake posi and 3.73 gears. also beefing up the auto transmission. what would my estimated quarter mile time be?

 

Welcome aboard thirdgen.org.

That really depends upon how well you modify the TBI for the larger displacement. Do it well, 12's aren't unreasonable. Do it poorly, expect to be stuck in the high 14's at best.

 

it would be nice to know what the specs are on the engine.

 

sorry here is the link to the engine on ebay ive been looking at it says its stock computer compatible but i doubt it. http://cgi.ebay.com/ebaymotors/CHEV-...spagenameZWDVW

 

It might be close to working with a stock truck 350 ECM.

Note they don't make any HP claims. The TBI heads are going to restrict a 383.

It should run low-14's, at least.

 

That engine gets re-posted by that company quite often. I was looking at it a few months ago and called them about it, they didnt have any actual numbers for it but their guess was somewhere around 250hp, which is pretty sad for a 383. Remember you get what you pay for.

 

Holy cow, you should be able to get a 305 TBI over 250 HP for a lot less than $2700!

Certainly since everything you'd have to do to the 305 you'd also have to do to the 383.

That's good o' eBay for you. Buyer beware!

 

I know, I nearly dropped the phone when they told me that. Honestly they didnt sound too knowledgable about what was going on when I asked them so they could well be wrong about the numbers. Like you said tho "good o' eBay" it wouldnt surprise me either.