Additional port work (finally completed)

[Nigel]

Good stuff, definitely looking forward to watching the progress!

 

[Mike T]

No definitive answers from the other forum regarding quench....was really hoping get input from a guy who stated that forced induction and nitrous engines "should have all quench areas removed" I wouldn't try doing this to another set of heads (chamber softening) until it's proven to make a difference at all.

 

[Mike T]

Few more pics for fun.
First 3 are of the 2nd port job (few years ago) and the last 2 are of the finalized (port job 3) exhaust port followed by the final flow numbers.

 

[belsie]

Great info and pics showing an immense amount of time!!! So when ready I am still waiting at the red light by the airport...................

 

[Mike T]

Thought I'd give a little update on the heads. The port work was such that I got dangerously thin on some of the port walls and the valve seats. They were to the point I really did not expect to get much Street use out of them. I have gotten almost two years of Street use and it just rolled over 7,500 miles with no issues

 

[Nigel]

Glad to hear it. Looks like a nice, very well performing package you put together.

 

[Mike T]

Glad to hear it. Looks like a nice, very well performing package you put together.

It went high 10's fairly easy. The current fuel system is the limiting factor now.

The exhaust seat are extremely narrow (maybe .045 -.050) and the exhaust ports are cut to within .065 of hitting water in some areas. It's actually very surprising to me that there hasn't been any issues. The car is driven 6 or 7 days a week in stop and go traffic so the heads have seen plenty of heat cycles.

 

[hensleyt]

I just noticed you run the DLS 210/210.Two questions is it the 114 LS and are you 1.55 TD or 1.65? With your good flowing heads where do you shift ? ( that was 3?)
My heads were just cleaned not ported stock heads eight years ago and I new any thing over.500 lift the bottleneck would show it ugly head .
I bought 1.55 rockers and DLS cam at that time. This and a small 5857 turbo only mods.And shifted 5200 rpm .
Two years ago I broke the engine ,bought a Zimmerman from Nick and a set of Champion heads. Running the same DLS 210/210 114LS .490 lift . I sometimes think with ported heads and the lower lift rockers I’m giving up some horsepower. I do shift 1-2 @ 5800 2-3 5600.
What is your thought on this combo? My new ET is 11.55 @118.

 

[Mike T]

I believe the cam card said 112+2 and I'm running the 1.55 ratio. Car is auto shifting 1-2 @5700, 2-3 @ 5490 and trapped 126 @5550

Contrary to what some guys have said I'm finding that cam to be very versatile. It has a nice smooth idle, good vacuum and in my case (manual shifting) will get up on the 6300 rev limiter in a heart beat.

I have no doubt that raising my shift point a couple of hundred will yield a better ET

 

[FASTV6HENRY]

Mike i think i am going the same route you did and porting my stock heads when i rebuild my motor so i am sure we will behaving alot of conversations on this topic... Great Job bud it is coming along awesome.

 

[Mike T]

Good to hear from you Henry! I know your schedule is tough but you should try to make the meeting.

For someone wanting to port their own heads I would suggest reading up on valve to throat ratio. Other than cutting through a water jacket I'd say this is where most mistakes are made.

For a street driven car 90% intake and 85% exhaust is the maximum, reducing each by 5% would be much safer because this material is needed for a good valve job. Everything has to be symmetrical ( though some throats are intentionally cut asymmetrically to complement port design). Once you understand the math for determining ratio it will become apparent that the smaller exhaust valves are less forgiving if you make a mistake.


I don't like completely eliminating guide bosses or huge intake ports.

 

[FASTV6HENRY]

I should be at the meet on Saturday.

 

[Mike T]

I've had a few people ask about photos lost in this thread. I don't know if it can be salvaged but ill start attaching photos as I find them.
These are the original stock heads that came on my car and they've been ported in several stages over the years. First photos I'll attach are after the first port job that was probably started 15 plus years ago.

About the only thing unique is the "chamber softening". I will remind everyone that this was an experiment on my part and DON'T go hogging on your heads in the chambers because to date I can't provide a definitive answer as to if this is a good thing or not. I'll go out on a limb and say it may provide a larger tuning window.

I'm not going to go overboard explaining photos but if you see something you have questions about quote the pic and I'll do my best to explain what the thought process was.

 

[Mike T]

This is the earliest example of the "chamber softening" that I have and it was done many years ago so every subsequent photo will be post chamber softening.

This is the exhaust ports and guide bosses after the 2nd round of porting. I slowly removed material each time I happened to have the motor apart. The heads evolved rather than happening all at once.

Shot of the exhaust ports with the heads installed.

Shot of the exhaust ports and the intake ports just barley opened up to the stock style intake gasket

Exhaust ports at what I think is the optimal size for most builds/daily drivers. The guide bosses are still mostly intact (other than mild reshaping) and the port walls haven't had an excessive amount of material removed which in turn keeps the port walls strong and resistant to cracking.

 

[Mike T]

The tools used to complete the following port work.

 

[TurboTGuy]

The tools used to complete the following port work.View attachment 367580

Holy revival of an old (but relevant) thread!

 

[~JM~]

Mike,

Do you recall height & width of exhaust ports? Any directional bias?

Thanks

 

[Mike T]

Heads removed from engine in running condition after a basic degreasing and clean up.

Heads disassembled preparing for the 3rd and final round of porting

Set up on an outdoor cart to avoid a big mess inside of the shopView attachment 4inch intake pipe.jpgSmall HF grinder with a stone that works well for SLOWLY shortening the guide bosses (not a fan of completely removing them). the small stones can be used in other areas as well. A significant amount of work had already been completed with the carbide cutters over the years.

 

[Mike T]

Mike,

Do you recall height & width of exhaust ports? Any directional bias?

Thanks

I can't remember a lot of the specific dimensions but ultimately the exhaust ports were ported to the carbon lines in the 3rd photo in post #118. I have a ton of photos that will show this more clearly later. The carbon line was the size of the perforated metal replaces that are common in the stock rebuild kits. Turns out that these gaskets are a little larger than the stock headers so the photos of the exhaust ports a few post back are a better representation of the stock header shape.

You can bell mouth the headers to match the large ports but they are welded on the inside and will typically crack away from the flange after opening them up. I opened my headers up to match the final port size but had to weld the tubes up around the outside and resurfaced the flanges.

 

[Mike T]

Actually I just remembered how the first exhaust port was acheived. The headers didn't have a gasket from the factory and it left a perfect carbon line of the header. If you'll notice the bottom of the port is rather squared and the top is a little more rounded just as the factory headers are.

On the 2nd go round after opening the exhaust ports up to the gasket I realized that nothing was really gained because the ports were larger than the factory headers.