Street Lethal

iTrader: (16)

Let me know if you guys would be interested is seeing the whole entire process of me working my 187 swirl port heads. Long story short, I need to swap out the early 416 heads that I worked on for the turbo GTA (don't ask why lol), and the 187's are just sitting in the garage and will give me the compression that I need. Figured the TBI guys would want to see the process and follow along. Here is a quick before and after of my 416 heads, and the 187's will be very similar when all is said and done. Let me know if you guys want to follow along while I do this, as I will be starting on them sometime tomorrow...

- Rob

cuisinartvette

Always up for a good head porting thread go for it!


Glutton for punishment with cast iron lol.

one92rs

iTrader: (5)

hey i would love to see it since i will be building my 350 early next year and have the heads sitting on the shelf.

car.ramrod

count me in to watch this develop

blackjack12982

I'm in, my 305 needs some more *****, this and the cam would be nice...

Street Lethal

iTrader: (16)

Alright guys, I removed the valves to see what I am working with here. So far I have to say, they are way better than the 416 castings in stock form. The exhaust ports aren't bad at all, although I will be taking down the valve guides all the way though. Intake ports aren't that bad, just going to open them up enough to be able to wiggle a quarter all the way through, then smooth them out. The intake bowls will be challenging though. Please give the pics a chance to edit properly in terms of brightness and size, as photobucket takes forvever to adjust the changes I made to them a few minutes ago...

Street Lethal

iTrader: (16)

Gotta say, I am very impressed with the 187 heads in stock form. When I did the 416 heads the quarter didn't even clear the orifice of the port. Once I smooth out the outer wall of the port, then remove some material from the inner wall, the quarter will be able to wiggle its way through no problem, then once I smooth down the floor and ceiling of the port it will be done... and on to the exhaust ports. If your reading this Chris (Fast355), you were right, these heads aren't that bad at all...

cuisinartvette

Whats the purpose of the quarter?
Are you actually cutting the guide shorter rather than just necking it down?
Roof is a good place to look for power imo floor..not so much.

Do enjoy seeing home jobs getting done.

Street Lethal

iTrader: (16)

The quarter is just a measurement that I go by. I usually do a lot of LC2 head porting and will mimic the aftermarket Champion heads with them, and I use the quarter to get me as close to equal cfm as possible until I can get them flowed by a local shop. From what I am looking at I will be removing the exhaust valve guide entirely like I did on my 416 heads (see pic below), as I don't need the heads to last for years and years to come, just for a couple of hundred passes at the track and these heads need to spool a T72 turbo with no obstruction. The intake bowl is very different though, have no idea how I am going to attack that area just yet. I'm honestly thinking about getting the EGR ports filled as well before I start on anything at this point...

cuisinartvette

Only mentioned concern with removing the guide as it keeps the valve stable from flexing..and helps keep it cool.
Anxious to see the numbers when you are done with them.

project89

iTrader: (1)

u can cut down the intake valve guide a good bit before it does become an issue,specially when using iron heads. i

RFmaster

@Street Lethal = Very interesting!!

Obviously, several question:
What are you plans for swirl ramps? Are you planning to shape them somehow???
Are trying to gasket port match (on intake side)?
Also, what are you tools of the trade?

//RF

Street Lethal

iTrader: (16)

I've been looking at the ramps for awhile the other night, and rather than just hack it all down, I want to keep the ramp but gradually bring it closer and closer to the wall as it is making its way up. The valve guide, rather than just remove it like on the exhaust side, I am going to blend it into the ramp on a slope in the same fashion. The area directly under the seat is so much cleaner than the 416 heads, and require very little removal, but there is a hump there that definitely needs to be flattened down...

The intake ports are tricky, as although I can get wiggle the quarter through no problem, that little factory obstruction on the outer wall is definitely going to cause some turbulence. I was thinking of having the machine shop fill that area in for me, then just blending it in and smoothing it out. If I try to blend it in without having it filled, I'm afraid I'm going to go through and expose the pushrod side because that area is very thin. I'll ask my machinist how much he will charge me extra to do this in conjunction with filling the EGR ports...

I am using a dremel w/carbide burr to remove the cast iron, and a regular and much slower power drill to both smooth it all down and polish them up. The combustion chambers need a little work too, as I need to remove most of the sharp edes, as well as do some work on the intake side because the valve appears to be very shrouded as is...

Fast355

iTrader: (2)

I have been trying to tell people for years the 187, 191, 193, 810 heads are not a bad casting when they are worked a little. Just be careful around the roof of the port where the swirl ramp meets the outside of the intake bowl, the cast iron is fairly thin there and doesn't take much to grind through.

I will be watching your results. I already know these heads have an incredible burn rate on them that is often mistaken as a tendency to detonate. With proper quench you will only need 26-30* of timing at wide open throttle.

gmstrong

thats some good porting,nice work.

Street Lethal

iTrader: (16)

Thanks guys, I already started on the porting and have been taking pictures of every single angle as I work on them. Should have this thread flooded with pictures soon...

Street Lethal

iTrader: (16)

Still waiting on the EGR ports to be filled, don't want to polish anything until that gets done because I am going to have to smooth down that area once I get them back anyway. Here is just a picture of the difference in the exhaust ports from the stock side on the right, then after I worked on the left side...

Fast355

iTrader: (2)

Can't wait to see what you get out of them. I was running my set on an engine that saw street duty with emissions controls on them so EGR ports were left in place. Other that that, I bet your flow chart shows your engine would like a straight pattern cam with a tighter LSA and about .480-.500" of lift to make peak performance.

Street Lethal

iTrader: (16)

That is exactly what I am going with, Crane cam (228/228) with lift essentially in that area...

1983Chimaera

I'm working on a set of 187s right now, planned for an LB9 with an LT1 cam for daily driver use with maximized efficiency. Should I port them more than just a port matching, or keep them the stock size with just polished intake and exhaust runners? So far I have them smoothed all the way thru, rounded the off the edges of the valve guides in the intake ports, port matched to the Fel Pro gaskets, and did a full bowl blend on all the valves. Also, where are the thin spots I need to avoid?

robertfrank

iTrader: (27)

I too am working on a spare set I've got sitting in my garage. I'm going a little wild on them and I almost have one intake side done. It's amazing how much meat there are to these heads that can be removed. I'll post up some pics when I get home later

Johnny Blaze

iTrader: (15)

I'd love to see some before and after flow numbers.

Those exhuast ports are hogged! Are your headers going to seal?

Street Lethal

iTrader: (16)

When I finished the bowls on these heads, I was amazed at how much area I was working with when the swirl was removed in comparison with the 416 heads. These heads honestly aren't that bad at all, especially when unshrouded. Here is a little before and after...

Street Lethal

iTrader: (16)

Yes, it is actually the same amount of cast (same amount of meat) between the bore and cylinder head bolt on my 355 block, and the amount of pressure during quench far exceeds that of exhaust back pressure, and if the head gasket will hold with that much material, the exhaust gasket should be fine.

1983Chimaera

So you entirely removed the swirl? I plan on keeping mine, since I WANT the effect it has on bottom end torque and throttle response, and since I'm building a street car with TPI I have no need for rpms above 4500 anyway.
What are the limits on the intake and exhaust that can be safely removed? I know the way next to the pushrods is fairly thin, how much can I remove?

robertfrank

iTrader: (27)

Here's what I've been toying with thus far. I had a set of 1205 gaskets laying around and this is the beginning result. I was able to open up quite a bit and yes I did punch through the beginning of the runner, luckily I can weld it up on the back side and clean it up. Here's the first few pics.

robertfrank

iTrader: (27)

Here's a couple more, I'm FAR from done but again I'm really amazed how far these heads can go..

1983Chimaera

Nice job! So a fair amount of the obstruction in the intake runner can be safely removed it looks. At the very least I can make it less of an angle and therefore less impact on the airflow, even if I don't go as drastic as you guys have. The bowls look beautiful, what did you use to do your porting? I'm using a dremel, don't have an air supply so I'm stuck with electromechanical means. So far just stones for major obstructions and 60 grit sanding rolls for smoothing and polishing. Next stupid question, has anyone ever thought of trying to weld a heart shaped quench into the combustion chamber, just above the spark plug hole, patterned after the Vortec chamber? If cleaned up after welding to be identical (within reason) on all the cylinders, and milled for flatness afterwards, would this work? What would the danger be of the weld not holding up to the cylinder pressures?

robertfrank

iTrader: (27)

I'm using both a dremel with a flex attachment (DAMN LIFE SAVER!!) and a single speed makita electric grinder with a separate speed adjustment dial. I usually go back and forth between my eastwood 80 grit kit and some double cut burrs. I like to use 80w90w gear oil for my cutting as it doesn't move around too much and it cuts nice.

1983Chimaera

I'm using a flex attachment dremel as well, but don't have any actual cutting bits. Can you link me (or show) what you use? I'm planning a Harbor Freight trip this weekend (gotta get new safety glasses, last pair failed me as I spent yesterday having a tiny flake of metal removed from my right eye).
Do you just coat the area you're working in with the oil? Or squirt some into the work area from time to time?
And btw, your pics are head porting ****!

Street Lethal

iTrader: (16)

Cute, but it doesn't work that way. You need to tweak your fueling in the prom to compensate for the additional air, that is the only reason why porting effects torque, and even then it isn't as substantial as you think when all eight cylinders are pulling air through a stock 48mm throttle body...

robertfrank

iTrader: (27)

If you have a true value in your area they sell double cut porting bits there. I use an egg shaped one I got for 16 bucks and it fits great with the dremel. I spread the oil around the area I'm porting until it works its way out, then wipe it down to check my work. My work is ok, I'm getting a lot better than what I used to be thats for sure. Thanks for the complement

1983Chimaera

I'm dealing with an LB9 with mass air, so 48mm should be more than enough to supply airflow (SLP doesn't recommend upgrading to even 52 until the 500hp mark), and the ECM should be able to compensate. If it was a speed density system I would be worried.

Fast355

iTrader: (2)

Actually in either case I would be more worried about the ignition timing aspect than the fueling. The stock tunes are fairly rich to start with and the slight leaning from altering the head flow can actually further boost the power output. The TBI heads burn much faster than the TPI heads, faster even then vortecs.

1983Chimaera

Hey Fast355, I sent you a PM about this the other day, if you get a second can you read and respond?

Street Lethal

iTrader: (16)

You simply didn't understand what I was saying. Your the one who is claiming to lose torque by removing the swirl in the bowls, and this simply will not happen when you correct your fueling in the tune, and this is what I meant by compensate. The reason why I brought up the throttle body is because whether you port the heads, or siamese the intake, you are still pulling air through a stock throttle body, so how much air do you really think you are increasing? I am running ported heads, a fully siamesed TPI intake, 74mm Turbo, and a stock throttle body, as well as the stock cam, and then a more aggressive cam, and have been tuning it with XFI up until the point. The amount of air being increased down low is not as substantial as you would think with the stock cam, and if your claiming that it would be detrimental to your torque then you need to show me a datalog, because it isn't. SD/MAF is irrelevant...

1983Chimaera

I'm going to run an LT1 cam, not a stock one. As said before, SLP doesn't recommend upgrading the throttle body until the 500hp, so the throttle body is not the obstruction in the airflow. I've already ported and port matched my TPI system, including a full polish of the lower intake, have already polished and bowl blended the heads and port matched to the TPI lower, and after reading this thread am going to attack the exhaust runners on the heads next. I've been reading the various threads on the swirl port heads and believe they would work together with the TPI system on a street car to create excellent bottom end torque and throttle response. I realize top end horsepower would be sacrificed, but on a street car intended as a daily driver using a TPI system this is a non-issue. I'm after fuel mileage through maximized efficiency, not quarter mile slips.

Johnny Blaze

iTrader: (15)

Head gaskets have 4 bolts with a tone of clamping force. Header flanges have 2 little ones with very little clamping force.

Header gaskets have a long history with small block chevys as being a pain in the butt to keep sealed.

Did you use a header gasket or header flange to match that port to?

Johnny Blaze

iTrader: (15)

This is the pic I am refering too.

How big are the openings of the center ports now? WHat size primary tubes are you running?

Street Lethal

iTrader: (16)

It doesn't matter how many bolts the head gaskets have that circle each individual bore, pull the head off of a 355 to 400 engine, and look at the thickness of the head gasket directly between the bore and the head bolt, and you will understand what I am referring to. Turbo owners will understand what I am saying by this right away, as the pressure during quench with boost is so great that it tends to essentially lift the head up off of the block (thus the term "lifting a head"). My point, was, that the head gasket will seal just fine in that specific area with the limited amount of material that it has between the bore and the head bolt, while holding in a substantial amount of pressure, and if that area can seal under that much stress, than an exhaust port to header primary will seal just fine. Clamping force has nothing to do with it...

Johnny Blaze

iTrader: (15)

I understand what you are talking about. I've pulled heads off a few, got a 409 sbc on the stand right now.

Maybe its that pic, but it looks like those exhuast ports are bigger them most headers.

If the number of bolts doesn't matter, leave a couple out and see what happens.

What kind of header gaskets do you use?

Street Lethal

iTrader: (16)

Again, your not understanding what I am telling you. You said, not me, you said that you wanted to keep the "swirl" because you wanted your torque down low, and I am telling you that is the wrong way to look at it. Removing the swirl will not lower your torque if you tune for it afterwards. You can't just remove the swirl and leave the tune alone, you have to compensate for it. I have no idea why you keep brining up 500 horsepower and SLP, I am telling you that any modifications that you make to the engine you need to correct in the tune. Torque does not disappear, it simply moves around depending on the modifications that you do. Disappearing torque is only an illusion to someone who does not know how to tune. Disappearing torque are for the guys that install Holley Stealth Ram's with no fuel tweaking and immediately wonder why they lost power down low...

Street Lethal

iTrader: (16)

Your not listening to what I am telling you. The area between the bore and the bolt hole has very little head gasket composite to seal effectively, and the bolt guide in the cylinder head is NOT leak proof, it is NOT air tight, do you understand what I am saying yet? If that little amount of head gasket can seal under that amount of stress from quench, then an exhaust port will be fine. I have been running my turbo headers for months, and have had countless passes, with no leaks. I am running a combination of both exhaust orange RTV, and a gasket. Primaries are 1 5/8", boost is set at 15 pounds. Just so you know though, Grand Nationals, even with trubo chargers from the factory, came from the factory with no exhaust gaskets whatsoever, and no leaks...

Johnny Blaze

iTrader: (15)

Holy cow man, ease up. I understand what you are saying about the head gasket being thin between the bores.

I am simply asking about your exhaust port SIZE.

Yes I am aware, many GM cars came from the factory with out exhaust manifold gaskets.

Can you install aftermarket tube headers without gaskets? Maybe, but I doubt it.

Are exhaust header gaskets known to fail? Yes.

Obsiously, you have figured out a way to make them hold up, esp in a high heat high pressure environment of a turbo engine.

What type of gasket do you use on your header flange? Paper? Copper? Aluminum? Carbon etc....?

1983Chimaera

Short of replacing the factory ECM with an MS-II, I am NOT going to mess with the factory tune on this LB9. I am going to replace the cam with an LT1 cam, maximize flow in the stock TPI and heads, use the stock high flow manifolds and a 3" exhaust, and keep the car in otherwise stock form. If I have to I can swap out the injectors for larger ones, or put in an adjustable fuel pressure regulator (about the same cost as a stock replacement nowadays anyway). I do NOT intend to mess with EPROM burning on the magically craptastical factory ECMs. I'm not after huge hp numbers, I just want to squeeze every last bit of mileage out of the LB9 as possible so my wife doesn't constantly complain about not being able to replace it with a nice shiny new $500/month car payment instead.
As for tuning, I've run MS-I on my '83 Z28 with a .040 over roller 327 with an LT4 Hot Cam for 5 years now. I'm not a stranger to tuning around airflow changes, but since my '88 LB9 is a mass air system, and I'm not drastically changing the airflow requirements of the engine (only decreasing the resistance within the system thereby increasing efficiency) it should still be within the capability of the ECM to adjust.

Fast355

iTrader: (2)

The stock tune on the TPI engines is HORRIBLE. I would at the minimum swap to an 89 tune, delete the cold start injector and optimize the timing advance. Many little tweaks can help out too. I do not like the MAT sensor under the plenum and prefer to switch it out to an open cage 6.5 Turbo Diesel piece. It responds faster and takes a better measurement of the air temperature in the manifold rather than the heat soaked manifold. I also strongly dislike the stock Bosch injectors and prefer a set of flow matched LT1 or LS1 injectors. To make the LT1 injectors fit I had to grind down the stands the fuel rail bolts to. Not a big deal just some extra work. I also made my stock regulator adjustable and adjusted the fuel pressure to 50 psi. The PE air/fuel ratio is very rich and the engine liked to be leaned down to 12.6-13.2:1 on a wideband, richer toward peak torque and leaner up top. I had to pull a little timing in the mid-range and advance it some on top. After I did minimal changes the car had much better driveability and performance. I changed the fan settings and adjusted the torque converter clutch settings to my preference. The OBDII GM ECMs are better than most aftermarkets and work fine in most street applications.

1983Chimaera

Ok, what years/models do I source the Turbo Diesel sensor from? As for injectors, I have a large collection of tested Bosch injectors, many pulled from HO 5.0L and 4.6L Ford applications, some from 3.8L supercharged Buicks and Pontiacs, sizes ranging from 14lb/hr up to 36 lb/hr. I have a homemade test rig I can cc the flow rates with and cycle cleaner through them.
Are the LT1 ECMs flashable? I have seen conflicting information on whether or not they are, and they have become readily available in the junkyards lately. If so I could swap out the stock LB9 computer for one of these and retune it. I just don't want to mess with EPROMS or custom chips.

1991sleeper

iTrader: (-3)

Street lethal !!! I know this thread is old .. I was just wondering if u ever got done with this build and how did it run compared to The ported 416's ? .. I'm about to be building a mild 305 w/ the factory swirl port heads 10:1CR 268/270dur etc. ... Lemme know how these heads worked out !!!

Street Lethal

iTrader: (16)

I still have them, but I couldn't use them. I welded a set of turbo headers originally using the 416 cylinder heads for the mockup, and when I finished the 187 heads and installed them they sat much higher than the 416 heads, and the exhaust side of the turbo wouldn't clear the valve cover, so I had to put them to the side. I have to admit that the 416 heads are a little more forgiving when it comes to porting the intake ports themselves (which is the bottleneck), but the bowls themselves are huge in comparison when you grind away the step...

1991sleeper

iTrader: (-3)

Well that sucks .. So how's ur 305 turbo run ? What all u got done to it engine wise ? I'm always looking for suggestions on how to get a lil more out of the 305 and there's just not many ppl that have done a performance 305 everyone goes 350 .. Like I said mine won't be nothin crazy but I'm hoping to get around 300 hp out of it