Would a 355 TPI with 305 heads, and valves that are opened up be a good motor for daily use? What kind of power would this motor make and how reliable would it be? I'm thinking of a swap for my 305 tpi thats detonating and is almost ready to probably die on me. Thanks.

 

Anyone?

 

It would make a fine dailly driver. I would find out why the 305 is detonating though.

 

I was told its detonating because the fuel isnt being burnt properly....and that is because something having to do with the valves being gunked up with carbon, etc etc. The 305 has 150k on it....ripping this engine apart and rebuilding it would be a waste....might as well go for something better.

What kind of power would a 355 TPI make roughly? I'm just curious if I should go this route. Thanks.

 

u should be able to easily squeze 300 out of it if built right. possibly more but remember you might have to upgrade other driveline parts

 

Yea......like my 700-R4 and since I only have a 2.77 rear gear ratio, I'll need that too....sigh.....

 

Why would you want to use the 305 heads? It would take some money to rebuild, then port them to get the flow capacity to feed your 350. I believe they have 58 cc chambers and with flat top pistons, your 350 would be close to a detonation prone 11:1. To bring the compression down, your now looking at dished pistons which, in most cases, cost more than flat tops. Go with a dedicated 350 head. Larger port volume and a greater potential for performance, all things being equal.

 

good 350s aren't gonna cost less than home ported 305 heads (assuming good castings)

 

...or I could get a 383 with 400hp/440ft lbs. from work for 2k...rebuilt, but for 2k its not bad...........................

 

get the 383 but it will not make 400hp with stock TPI.

 

I'm kinda tired of sensors...might do carb....also....I know it would need a rebuild, but of what kind of magnatude.....my 700R4 to handle that kind of power??

 

Assuming you know how to port heads, have good templates to work from, understand concepts like flow, short side radius, port design, etc. Many home porters think they do but when tested on a flow bench, often times they've done more harm than good. It's an art that I think too many people don't appreciate. Why not get a completely rebuilt set of heads from a firm like Aerohead Racing (317-862-0223) that have been vatted, decked, new guides, new stainless 2.02 valves, new springs and retainers for upto .525 lift for $359/pair? Now you got a choice of chamber size (65cc or 76cc) and you can use the cheaper hypereutectic claimer flat-tops for $120 or so.

Phantom,
I'm guessing you understand that you won't be able to use the 305 heads on a 383 and maintain streetable compression....right?

 

I already scratched the idea of 305 heads......the 383 comes with heads already matched to the application....if i build a 355 though, I wont be using 305 heads then either.

 

With no help at all home porting might not be a good idea but there is a wealth of informstion on this site about home porting. Many ppl have done it and had very good results. Do a search under sitting bull - he did it and had very good results the first time out.

 

I concur! There are many knowledgeable people on this site. Ask questions, for sure.