Philly#1 Lex

iTrader: (2)

Hey what do you guys think of port and polishing the SC400
I got this guy who will port and polish the heads, etc. in the engine for $150:eek: I heard it could give around 20HP Through the whole range. What do you guys think I should do

carnal_c30

hmmmm i doubt 20hp honestly.... but I duno you might get sooommeee gains if any... but hey if the manifold is off your car i say go for it!

Hermosa

Hey clean the throttle body real well. I believe there were posts about gains from cleaning the gunk out of this. Also have you ever taken a look at the inside of your intake manifold? The nasty film on there is probably enough to slow you down. A good cleaning might help but 20 horsepower? Who knows. Better throttle response maybe. $150 is a steal. I would run with this.

Taka

I'm not sure about the price range but I would go for it if it's my local and $150

Philly#1 Lex

iTrader: (2)

The deal is over here in Italy where I am stationed at. Has anyone ever had this done before Hey does anyone know how to take off the heads Thanks for the help and suggestions.

Hermosa

R&R on the head is probably going to cost you over $1500. Buy the manuals. They will help immensely.

Philly#1 Lex

iTrader: (2)

Hey Hermosa or anyone should i get Tex's headers from australia before i decide to port and polish Or stay with the stock headers. And is taking the headers off and preping things for the port and polish difficult

Hermosa

The headers kind of eliminate the stock cats so you would have to custom make the midpipe if you wanted them back. The headers will add 16rwhp. You will want tuning also so you may need an S-AFC or Custom ECU. Port and polish can be labor intensive. I have seen quotes as high as $2500.

Onelove

With porting you usually get what you paid for. Anyone with a Dremel can port, but the results can actually cause you to loose HP. For our racecar head I know we pay in upwards of 2500 for the porting, but the end result is well worth it to us. For 150 it's possible to get a good job, just doubtful.

Miles B

Anyone know much about working on the combustion chambers to lower the compression ratio in preparation for turbocharging? Does it have to be as high precision work as for a NA engine?

I have heard that with forced induction, you mainly just worry about flow numbers (and of course, enlarging the chambers), and you don't have to worry quite as much about the exact shape of the ports for intake velocity etc... If it's not too hard, might try this, as thick head gaskets are expensive, and a dodgy solution.

Anyone?

Philly#1 Lex

iTrader: (2)

The guy I am going to use to own a shop in Florida and he has down all of port and polishing on his bike and some cars back in Florida. The guy is doing this on Base over here As long as i do the work to bring him the parts Does it sound like a fair deal Plus Hermosa, I didnt Know Tex headers were that good. Where would I get the midpipe from and how much does it cost to get made Thanks for the help Hermosa and everyone else. I have a 92 SC400 43000

SCV8

I'd give it a shot,will do so soon myself on my '92;expect to get the same increase as you've mentioned.

Keith13b

iTrader: (3)

Head porting for $150? Or port matching the manifolds? Big Difference.

For only $150 that must be a hell of a friend. $1000 is a good deal and there are few places that can do it right.. Typical cost is usually ~2000$. If he's doing it free hand be very cautious as he can cause more harm than good. Normally they are done by a a highly calibrated press with strict tollerances. Heads are expensive, so if he messes up.........

Gains of 20hp are common for porting, but only if done right. It is possible to lose power by doing this too, so keep that in mind. I have only heard on one person porting the heads on a 1UZ, and it wasn't cheap, but gains were achieved.

Rotary cars (RX-7's) can easliy be ported freehand because there is a lot of meat there to be removed, but piston heads are a different story. The water jacket can get pretty thin in spots and the port has to be perfectly straight to prevent turbulance.

If you do the exhaust work, then it will most likely have to be custom bent by a shop. Its fairly cheap. I've got Tex's headers and plan on installing them over the next 3-day holiday. They will replace the factory cats, so if you have emission standards, you will need to buy 2 cats and have them installed after the collector.


Good luck,
Keith

SCV8

So true about the use of caution,so just how do you use a press to aid in porting?
I could maybe see how having the head setup in a valve guide press could help to guage the material removed or something.
The vane that separates the two intake valves in each cylinder's port can be made to be alot sharper on the edge that the fast moving air hits.

Keith13b

iTrader: (3)

I used to work at a shop as the rotary guru, and port and build rotary engines. The shop had a computer press that did port jobs on boinger engines (still have the rotary blood in my veins). Basically they set the heads on this clamp. Then they point to all the points of reference on the heads and mark them on the computer .....like the top on the port, press a key on the computer, then point to the lowest end of the point and press a key in the computer....get the drift? Then you enter the specs of the original port, and the specs of what you want to create. Then just press a key and the porting is done automatically by the computer. It works kinda like a plundge router. The drill moves to the port; then plunges down slowly, adjusts and does it all over again. The secret is to make the port perfectly staright. When finished, a tech will polish up the rough edges and clean.

Porting a a head freehand would be a ******, and seems like it would take forever and leave a lot of room for uneven paths.