TurboToyotas im doin the askin about the whole port and polish deal so its your turn now to explain to me why its a waist of time and money



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Just Insearch of Knowledge So I Can Save Money and Be Fast

p.s. dont give me dat stuff about if you want to b fast you should have bought another car......cuzz that saying could have gone for serveral other cars out there that are running 12s and faster........

 

I'm no expert, but I did port, polish and balance a GM V6 30 years ago - a whole lotta work!

I would say that porting is a good step in making an engine more efficient, but you don't really get the benefits unless the motor is carbureted and throaty. Also, the more gross hp, the more you need it. On a small motor like the xB you don't get a lot from it pound for pound, but I don't see where it hurts.

I wouldn't polish a carbed engine today. I would take off mould flash. Fuel misture needs some of the turbulence created by unpolished surfaces. However, this is all moot in a fuel injected system.

You will get the most benefit from a balanced motor but you have to take the engine down to do that. Well worth it if you want the most performance. You can put a turbo on a Vespa, I just don't see the point. If you want serious performance, be serious in your approach.

This is all my old-school opinion. I have not stayed up with all the technologies, so take it in that light.

 

a port and polish will make the engine breathe more efficiently, but you will hardly see the benefits on these engines unless you are going f/i

if you are looking for brute force power, at minimum cost, you could skip the port/pol.

if you are looking for the best-of-breed build (crossing all your t's and dotting all your i's), where cost is no object, then p&p

i don't see how it could hurt anywhere other than your wallet.

 

I am far from an expert, but even with forced induction I think you will need to be running stand alone engine management to realize any of the benefit of a port and polish job. As it is, piggy backs are doing well enough just getting the engine to run properly when equipped with forced induction.

I am sure Todd, and other more experienced turbo builders will have much more thorough and knowledgable responses.

 

There are allot of reasons why I woulnd't recommend having head work done.

1-There are allot of shops that say they can do it, just like many people say they can tune. Nothing is further from the truth.(in my opinion) There are only a handful of shops that I would even trust to do headwork. And they aren't cheap. Plus good work takes time and believe me they take there time.

2-Cost vs benefits. Unless you are going to spend allot of money doing the entire build its not worth it. You need achieve a balance to correctly take advantage of headwork. Not only is the air moving through the head but how is it getting there and how is it leaving? You would need a really good intake manifold and an efficent exhaust manifold to take advantage of a good flowing head. Not to mention the fact of how are the factory cams going to react? Are they going to be a hinderance? Most likely. To find a shop that could port your head to increase flow with the factory cam specs is going to take time and allot of $$$$.

Granted if you were to port n polish your head with the factory intake manifold and say you were using my turbo kit you might see some slight increase in power, but at what cost? Not worth it for say 5 or 6 more hp when you can spend significantly less money on a boost controller and tune up the boost 1 or 2 more psi and get more power.

Now if you want to make allot of power and are going to build the bottom end I would skip the headwork and concentrate on the valvetrain. Look into springs/retainers and possibly valves. Just depends on how much power you are going to try and make.

Hope that helps.

Regards-

Todd