Ok I know someone has done this but i can find anything on the search!

Ive got the whole top end of my 3.1L apart for finishing up some mods and here are my questions,

1. Is it possible to obtain any Hp/ flow out of gasket matching the upper and/or lower intakes?

2. I cant afford the top end 3.X00 swap and the head are about to be off the car. If i match/port the heads too, will it help flow a little?

3. How the hell can i get rid of the air pump and still have any clearence for the serp. belt not hitting the radiator hose? I dont have a/c on this car but i need the room on the other side despritly.

4. I have some 19lbs injectors sitting in the garage/ will these be ok on the car for a N/A set up and in a few months a turbo set up? Dont plan on makeing more then 200Hp on the turbo for a while till i can afford to add fuel requirements/ignition 6AL box. Stock is 15lbs correct>????

THANKS for any tips as the winter projects have now begun since the
insurence is off the car.

Ive taken this cars motor apart so many times that i should have just waited until one time to do all the mods..lol Hardest part is taking off the ungodly heavy hood, by yourself!!!!!!

 

Heres one of the ports matched/still needs a little work though. On the middle intake manifold.

Im afraid to get any closer to the gasket envelope than the one already is.

I want these rough right??? Not polished. I want the air to swirl..right??

I have acess to a flow bench and look to see what it flows after. Any idea what it flowed first since i didnt flow the complete stock one.

 

the car will run a bit rich on the 19lb injectors but itll be fine for awhile... i did it on mine didnt notice any real differences. with a turbo you wont have much room for boost at all on 19lb maybe 2-3 psi.

 

2-3 psi?? jezz how about 24lbs injectors? whats the ratio on injectors a extra # per Psi??? so 24 will let me get 9psi?

 

I would open the diameter of the port a tad bit more. Cut the paper gasket with a razor blade or scissor to desired diameter (always measure your work), lay the gasket back on the manifold and mark the exposed area with a pink marker and start porting no more than that. This is how I opened up the ports on a turbo Buick cylinder head. You'll get an idea from the pics, I used the same method as described...




No, you want them smooth in that area because it is before the injector. The only time you want a rough area is when the air and fuel come together, as the rough surface helps with fuel atomization. Prior to that, the rough surface will only slow the air down...

 

Look for an '88 or '89 2.8l f-body in the JY. Some have a small idler pulley on a spider set up in place of the AIR pump.

Stock is in the 15 #/hr range. I wouldn't put the 19's in until you get into tuning the ECM. There are several changes required in the tune for the larger injectors.

RBob.

 

Ok heres a newer pic of what i did this evening. I know ive got alot of smoothing to do but its a start. And i need to make the 4th port over from the left a little wider. About .1 inches. After I polish these, which should be fun.......Ill flow bench them.

 

Here is another pic after smoothing out the ports a little more... Ive heard both smooth and leave the intake rough... for turbulence..

 

I can't see the recent pics (photobucket is blocked at work) but a rough texture is always better on the intake side.


I use carbide burrs for ferrous metal on the whole intake track, it leaves a very nice surface. Do some google searching for the golf ball effect.

 

Here is the upper intake at the throttle body. There was about 3mm of circumfrince that i added. Matches the TB perfect.

 

I am curious about the V humps in the intake side of the heads??? Should i leave them as is and stay away from them? I was thinking that they look as they add a shark fin effect and actually help flow. The heads are still on the car but tommorow as soon as I get home Ill be taking them off. Thanks for any info fellow thirdgen V6's!!

 

its a good idea to leave that vane in there as i helps increase the flow into the engine. dont change the camber of it but you can remove the casting flash. most of the gains will be in the bowls.

on a side note, i was thinking of trying to increase the flow of the stock middle intake by siamesing the bottom of it, anyone see a problem with that? as shown in pic

 

on a side note, i was thinking of trying to increase the flow of the stock middle intake by siamesing the bottom of it, anyone see a problem with that? as shown in pic[/quote]


ok thanks for the tip!
Never thought about siamesing it. Am curious to see if anyone has tried that.

 

ok thanks for the tip!
Never thought about siamesing it. Am curious to see if anyone has tried that.[/quote]

im about 1400 miles from home otherwise id check, do you think you can check and see how much material is behind those areas? just want to know how deep i can make that before it gets too thin and cracks.

also, when i ported my irons, i didnt grind into the floor much at all since the ports already sit low in relation to the valve. i raised the roof(lol), and widened the ports as far i could get them.

 

which are are you talking about?? The thickness where at ? My intake is right next to me so i can measure any thing ya need.

 

awesome, thanks! its the area behind the markings in the pic. if i were going to grind the partition in between the ports, how far could i grind(depth) until i break thru to the other side?

 

to be safe id say 5mm but like 8mm tops

 

wow thats only a heavy quarter, not much lol.

 

yea theres not much there.. really dont know if it would be a positive effect, seems like it would flow worse since it would hard to make it a smooth transition.

 

got the drivers side head off.. sure isent much port area on the exhaust side.. Id be hard to fit your thumb in there.

Any one have good pics of the lower manifold going to the heads, being ported?

There are alot of curves on the lower part of the lower manifold and i dont wana mess up what the factory had going with all those curves

 

Might effect torque a tad, but I don't see any real problem with that, especially if your planning on running a turbo. Either way the air is still making it's way past a particular valve size, and siamesing the ports on the intake only shortens the path to the cylinder heads, and raises RPM potential...

 

Heres the crappy *** heads GM gave us. Amazing how small the exhaust side of the heads are.

 

seems as if these factory intakes are for a faily low tq curve, id like to turn 6K tops.

 

I started the porting on the exhaust side of the heads today. They were so crusty and rough when i first started. Takes about 1 1/2 hours just to port the thing. Probley only a few min to polish the thing.

One queston....why is there 2 exhaust ports on the center exhaust valve???

Bottom pics you can see how much extra cast iron there is what the difference in size looks like after gasket matching.

 

thats the egr passage

 

wow i must be brain dead when i was trying to figure that out..I new that!!

 

One head is officially done. Took about 8 or 9 hours in total. Here are some more pics of the head along with another question that i hope someone can answer. Look at the last picture for my question.... Thanks!!

Valve guide area..


Finished exhaust ports..smooth as can possibly be!!


Here are my valve covers after i cleaned them up. They seem to match my black intake very well.


Here is my question.. should I gasket match or port this part of the intake manifold its the lower that attatches to the head. Should i just match up the sides and leave the curve alown??? I dont want to mess it up by gringing away on something that helps the flow. Thanks for any advice!!!

 

you can take the guides down much further, most of the flow is right there.

 

Are you taking about these runners?

 

Any tips on the injector runners?? Should i clean up a little of the excess alluminum in here?

 

No, he means the guides in the bowl area, like this before and after on mine...;




Clean that area up too, straighten it all out, like this....;

 

Thanks so much for the pictures. I know what you mean now. I just wanted to make sure before i messed up the injector bosses/runners.

 

Ok here is the valve guide one of the heads that i was worked on this afternoon for a little bit. Can i keep on taking more meterial off or is that enough??? I havent really done much to the EX valve guide yet.... Thanks!

 

You can take the valve guides all the way down if you want to. I did both the intake and exhaust valve guides that way on the 416 heads that I am currently running on my turbo 305, no problem whatsoever...

 

Also, focus on the diameter of the orifice as well. I'll color in the area that I'm referring to. Just try not to "nick" the valve seat when you do this area of the orifice. Compare your pic to the one that I edited, then the pics of my cylinder head work. You will see the area that I am referring to. The idea is to open up the orifice, and smooth it all out. Again though, try not to nick the valve seat, and don't go too deep around the orifice. Just clean it up some...

 

Ok so basically I am boring out the diameter of the orifice?? I just have to keep the size of the opening smaller than the valve seats. Right? Ok thanks again for the pictures!!

 

Yes, the idea is to increase velocity by providing a direct, albeit smooth, pathway into the combustion chamber. Smooth out the area around the valve seat, but don't cut too much around it because the valve needs to seal, and don't nick the valve seat. If you do nick them by accident, no biggie, just lap the valve seats over...

 

Ok thanks again!

 

ive been so busy with work and my tt iroc i havent had a chance to reply to ur pm, but give me a lil time and ill dig threw my photobucket account and get u some pics of what the ports should look like when u are done.

the main area u need to put alot of work into is just under the valve seat just like streetlethal pointed out.
stock if u take the ex valve out and drop it in the intake side the ex valve will not drop past the valve seat, this is the major choke point on the iron heads. there and alot of work around the valve guide

i have actually come up with a port shape that does not require the vane in the port entry, but i dont recomend going that far on a mostly street driven car

 

here u go

 

Thanks for the pictures project89 and streetlethal!
I opened up a few of the valve bowls last night and I did see what your talking about,.... the ex valve wouldnt even start to fit in the bowl, but now it goes all the way in the intake valve bowl. That is what iI used as a reference to match the intake bowls to be close to the same size. Heres pics of a few of them. They look better??





I was a little scared to take too much off near the valve seat but like i said for a reference the exhaust valve falls down to the bottom easily now.

 

Excellent! Good work. You can take down the valve guides all the way if you want to, but again that is of course optional. Either way, very good work....

 

What tools are you using to do the work?

 

Any decent dremel drill kit will do...

 

Yea im just using a dremel and a whole bunch of various bits, sanding drums, and carbide bits.

 

clean up the valve guide area better and blend it in to the backside of the bowl area real well.
also dont forget to smooth out the short side radious, when u are done with that lay a head gasket on the head and mark around the intake valve and take out the extra materal, this will give more room for the air to flow out the side of the valve were its near the chamber wall. do not cut the material back stright up and down though,cut it on an angle with the part of the chamber furthest away from the valve face having the most material removed

i think i have pics of this done on my set of heads ill have to take a look

 

grabed this off google real fast

see were the chamber used to be round and now it has 2 cuts in the sides that stick out
thats what u want to do just dont cut past were the headgasket sits

 

Project89 do you mean to take the area out that i hi-lighted?? Just stay away from the head gasket envelope?
I attached the pic.

 

How critical is the balance across the runners and chambers with regard to the amount of material removed? If the runners and chambers all 'look' the same is there any need to flow test or measure chamber volumes or would that only be needed for a "super" tune?

 

yes

in an ideal world each runner should be flowed and worked till they flow the same, real world for what most of us aare doing it dont make a bit of difference