[PMD1969]

Originally Posted by TheSilverBuick

Honda parking lot =D

lol

[Jack Gifford]

So... is "metric calibrated rocks" some kind of code-word?

[Bill Hanlon]

Originally Posted by Jack Gifford

So... is "metric calibrated rocks" some kind of code-word?

No, just a lame excuse for humor.

[TheSilverBuick]

^^^^ As a professional Geologist, I approve of this humor.

[TheSilverBuick]

I'm heading to California after work tomorrow and heading home Monday, and should round trip around 1,100 or so miles I figure. I did a few minor things and upgraded the radiator fan assembly. I backed off the cam advance a few more degree's so it should be right at 4º advanced. It seemed to be struggling to get to crest 5,000rpm so this should help. Also smeared some ultra black RTV on the top of the underside and top of oil dipstick cap where the stick comes through the cap in an effort to seal it better for the vacuum pump. I found it whistles from time to time.

It's supposed to be 108 ºF in Las Vegas on Monday when I am heading home, so on the radiator side, I got one of the $50 HHR fan assemblies with shroud and it matched up mint. I shaved about 1/4" from the front and it cleared everything nicely. The tabs that stick out the side touching the tanks keep the fan a good distance from the radiator. At least I hope I haven't goofed up and find my self with a holed radiator. So far it doesn't touch and I can feel the air being pulled at the grill. The engine is running in this picture.


From the top. I put a slit of rubber hose on the top and bottom. Going from ~1,250cfm to ~3,000cfm ought to help. The battery voltage was good at the warm up high idle while I had it running as a test, so on the fan menu of the MegaSquirt I turned on the "idle up" option to make sure in stop and go traffic it wouldn't be depleting the battery. The GEN light lights up to let me know if voltage drops below 12.2v.

[TheSilverBuick]

Finally got the engine out today after work and I pulled the head off. The cam and followers are looking good.



The pistons were carboned up as I expected them to be given the blue smoke on start up and the substantial blow by.


Chambers also carboned up as expected. Valves appear as I'd expect.


In the ports, the intakes looked pretty much as I expected with some carbon on the back side of the intake valves, but the exhaust's color has me surprised. I've never seen the yellow/tan exhaust valves, but some engine people I trust say it's normal, so I'm good with it.


I am a little surprised at the clean spot on the valve stems,but otherwise pleased with how clean the port is.


All my exhaust port photo's are over exposed, but the yellow color is just odd to me. Nothing surprising about the ports to me.


Tomorrow I'll disassemble the head and start the measuring of the chambers and porting. I think the port work needs to be prioritized because I want to take the head to the machine shop next Friday, so I need it done before then. I'll start on the short block when I am done with the head.

[TheSilverBuick]

Pulled the valve and springs off the head and did a bunch of measuring today. CC'd the chambers and the pistons valve reliefs (both types are surprisingly within 1cc of each other) as well as measured how far the piston was in the hole and how thick the head gasket is. Crunching the numbers still show I have very low compression, PipeMax calculates it at 8.022:1. The service manual advertises 9.0:1. The chambers have a horrid 76cc's, the pistons have 8cc valve reliefs (much less than I figured), the pistons are 0.034" in the hole, and measured head gasket thickness was 0.047", which is the same as the new gasket I have, so I'm guessing it crushes down to some number, probably around 0.040" for my compression calculation.

My handy dandy home made valve spring compressor worked like a champ.


I also outlined the ports to get an okay estimate of the current port area. Light coat of oil on the port, and a blue shop towel works great. I did the chambers to so I can try and figure out how much compression I can try and gain back by shaving the head.


A pane of glass for some back lighting and traced them out on some scaled engineering paper and can do a rough calc of area here, but I'll probably digitize the shapes to scale and let some computer software calculate the areas. Then I'll average the intake ports together to use as an intake number and then average 1 & 6 exhaust together and then 2, 3, 4 & 5 together for the two exhaust numbers.


Now I can begin the porting!

Doesn't this make a cool back to back picture? Like x-ray vision or something =P


.........................

[PMD1969]

You must be using a Felpro head gasket as IIRC they are the only ones on the market yes? Shaving the head will change the distance of the belt travel and cogs so how much will you need to remove to make things work?

I have looked at the same problem since wanting to go both ways. I have a Sprint motor that I want to take a little compression out fo which the Felpro gasket does. But going the other way with my spare OHC which is a 1 barrel the timing might be screwed.

What are you doing to solve this?

[TheSilverBuick]

I have the Sprintbird adjustable cam timing sprocket on it so I can correct/adjust the timing no matter how much I shave off it. The sprocket has far more adjustment than could possibly be shaved off a head. At the moment, I'm thinking I'll tell the machinist the shave as much as he is comfortable with.

I've roughed in all the chamber re-shapings, but need to cc each one to balance them out, did minor rough clean up of casting marks in the ports and have opened up the area behind the valves of two of cylinders.

The first time I ported a set of heads I swore I'd never do it again. There is a reason professionals are paid good money, as my limitations are quite apparent. Hopefully though there is a net positive result.

[TheSilverBuick]

I 100% agree with you Hank on the valve job, and this head can seriously use one. The back side of the valves can certainly use improvements as well, but out of scope for this head. These engines are so sensitive to valve stem height, that if the seats were not installed and cut to the correct depth that it'd eat the cam among other things. So I just don't even want to open that pandora's box with the machinist at this time, I want a same day turn around time, so he is just going to shave the head, probably shave the intake/exhaust surface as well and maybe knurl or insert bronze valve guide seals.

Got the head as done as I'm going to take it. I was going to cc the chambers and balance them out, but I think I'll wait until after the head is shaved to cc them and balance them at that time.



A quick measurement of the before and after intake port diameter where it necked down looks like a bit over a 1/4 square inch was added to the cross sectional area behind the intake valves, which is about 17.5% more area if my math holds. Circles are funny things.

[Half-Inch Stud]

Wow; looks super. Wish I had ported me OHC-6 Heads.

Suffering DRSSS. Question: what CYL does a fells put the timing light on to set the TDC timing advance?
Me thinks it is CYL 1 but me memory is playing trick like I used CYL 4 or something stupid. (I use CYL 6 on me V8 every time).

[TheSilverBuick]

I've always used #1.

[TheSilverBuick]

I grinded and chiseled out the rivets holding the internal oil baffles in place, so now the block is about as bare as it gets.

I once again proved to myself I cannot drill and tap straight (much like when I cut things...), and because I find nothing sacred, I drilled some holes in the exhaust manifold for future EGT probes where the A.I.R. injection ports would go that will be functional enough. For reference, only the '67 exhaust manifolds actually got the A.I.R. set up. I ground down the choke's heat well casting as well so when I get EGT probes in there I won't have any interference turning a hex nut.




Cleaned up and smoothed out the number 1 and 6 ports as well.

Number 1 looked okay, just a little on the bottom right and smoothed out a bit of casting flash further in.


Number 6 on the other hand had all sorts of over casting! So I ground it out and smoothed it up.

[TheSilverBuick]

When the machinist looked at the head his opinion was that the head has had some work done to it in the past. He said that the intake guides had been replaced with new iron guides and it looked like the head had been surfaced before. So he ground the valves and seats to a fresh 45* angle, pulled 0.030" off the bottom and a bit off the side to flush up the intake divider. In a mis-communication he cut down the exhaust valve guides so valve guide seals could be installed on the exhaust. Oh well, it's nice work The block had 0.035" shaved off the top, which should leave the pistons 0.003" in the hole if my measurements were good. I'm going to re-measure it when I have the short block back together, but crunching all the numbers now takes the compression from 8.02 to 8.58. I only lost 1cc from before my chamber work and cutting the head, from 76 to 75. I measured out the port lengths as well and was shocked at how consistent the were. All measurements port to port only varied by a 1/16" which is likely the margin of error of how I was measuring them (with a wire). Averaging the top and bottom measurements the intakes were 3.125" long and the exhaust were 3.063". I think it will want an 8" runner on the intake manifold for an 11" induction length.

So it turns out there is not a whole lot to do for the intake ports, and a bit to do for the exhaust ports. It looked like the

Freshly cut so the intake dividers are flush with the gasket surface.


The intakes against the two gasket types I have.


The exhaust against the two gasket types I have.


The valves were re-ground. The stock 45* seat angle. The black marks are just sharpie marks.


The head with the cc's written on it.


I finished all the metal work on the short block. Got 0.035" shaved off the deck and flexball honed the cylinders. I tapped all the spots where the baffles were riveted in with 1/4-20 threads so I can bolt the baffles back in after I add more baffling behind them. I've hosed off the block inside and out and dried it out with compressed air and fogged the cylinders and deck with WD-40. I'll probably re-paint it either tomorrow or during the week. For now I have it bagged and sealed.



Tomorrow I'll work on the last bit of head work, get the head cleaned all up and possibly re-assemble it, with the new valve springs. Get the pistons cleaned up and install the new rings. Work the over the baffling and re-install them. Finish working over the intake and exhaust manifold ports with the die-grinder and if I get really really ambitious I'll get the cylinders real cleaned out and install the crank and pistons. I need to shorten the head dowels and make sure the head bolts don't bottom out.

[TheSilverBuick]

I worked on adding extra baffles to the existing baffles and touched up the paint on the block. I'm hoping the baffles help as I've done no research on effective baffling. The 1/4-20 screws are loc-tite'd in.

This is the stock oil fill tube baffle. It's easy to see the light where the oil fill tube goes. This is also the side of the block the crankshaft slings oil upwards.


So I riveted some sheet metal to it to try and trap the slinged oil and let it run down the sides. I was holding it upside down in the picture, so I rotated the picture. I had to notch it afterwards because of interference with the oil dipstick, so it got a bit rough on that side.


In place and no more light seen. Then from the top, when adding oil, it should hit the baffle at the top and run down the sides.




The stock baffling on the PCV port. The light is the hole for the PCV tube.


This one I really wasn't certain what to do for it, so I just made some air flow interrupters that I hope cause the oil to drop out. Most the air should change directions at least twice before making it to the port.


The baffles push up against the block, mostly sealing against it, so again most the air will change directions twice before getting to the port, hopefully dropping oil along the way. The shiny brass fitting there is a port I added to measure the crankcase vacuum/pressure. I'll have it hooked to a vacuum/boost gauge and maybe someday to the megasquirt as something to datalog.

[Donovan]

I think that chamber relief at the bottom of the intake valve as well as the larger one will pay off! The chambers look great! Conventional wisdom says your bottle neck is now the throat and short turn. Exciting work.

[TheSilverBuick]

I measured the ring gap this morning and found some interesting numbers. Measured it 1.5" from the top and measured it 4" from the top (3.53" stroke) and the taper changed the gaps about .0025". I didn't back calculate what the bore diameter difference was. BUT the big difference is between the old and new rings, or at least the one of each I checked. The old ring had a gap of .055" at the bottom of the cylinder and .057" at the top of the cylinder where as the new ring had .0185" at the bottom and .021" at the top. That is a huge difference. Doing the calcs for the 3.905" bore, at .004" per inch of bore for N/A applications, .0156" is the minimum gap recommended, and using .006" per inch for boosted applications I get .0234" for a minimum, so .021" will probably get me by if I put a turbo on this engine because the cast pistons will probably require keeping the boost down anyways. I pulled the recommended gap numbers from the Mahle website, whom the rings are made by.

The tighter ring gap ought to help out in the compression and blow-by departments.

Stuck the pistons in it and retouched up the paint on the intake and exhaust manifolds as well as the head. I cleaned up the oil pan and will re-paint it tomorrow as well as touch up the paint on the other stuff. Tomorrow I'll assemble the head and start the final assembly of the engine.

Still some ragged looking pistons, but hopefully bumping the compression up a half point or so, theoretically improving air flow in the head and tightening up the piston ring gaps net me some gains in horsepower and reduce overall oil consumption.


Pistons all in and oil pickup installed.

[TheSilverBuick]

Got the engine all together now. I need to put oil in and prime the system up still as well as install the fuel rail and throttle body. I found a couple of the upper injector o-rings cut or shaved, so I need to do some work on the fuel rail and further round out the entrance to the injector. The #4 injector that gave me the most problems was the worse. Eventually I got it so none of them leaked while running and driving, heck even held 20psi after the engine was shut off, but intermittently I'd have issues. I only had two new o-rings so I need to get a box of them tomorrow from NAPA.

I set the timing belt in place and if my math holds between the thicker head gasket and then shaving the head and block deck the cam is 0.045" closer to the crank and would retard the cam timing by approximately 2*, which is what I saw when I tightened everything down. I reset it from 2* retarded to 4* advanced.

I brought the wiring harness in the house. I'm going to set my card table up tonight with the soldering iron and lengthen the harness by about 8" while watching a movie so the plugs clear the back of the head.

I did more work after I took the pictures, the balancer and trigger wheel are on it now, as the cam timing isn't set in these pictures because I don't have the TDC mark that is on the balancer.

You can see the brass fitting I added below the red PVC tube that I'm going to hook a vacuum/boost gauge too to read the crankcase pressure. I may eventually hook a MAP sensor to it and datalog it with the MegaSquirt.




I touched up the paint on the belt cover as well.

[TheSilverBuick]

Got the engine in, bolted up the transmission, torque converter, etc. Finished all work under the car, which was my main goal today. Tomorrow I plan to install the alternator and radiator and probably hook up the fuel line and throttlebody. I forgot I need to replace the rear fuel filter at minimum and see if that was the fuel starvation issue. Then it will probably be Wednesday before I change the fuel filter, but then should be good to fire it up.

All set in. I wrapped the wiring harness in friction tape and it compacts down much nicer and fits between the fuel rail and cam housing now.


I spent a couple hours last night adding about ten inches or so to the wiring harness. About 30 wires, two solder joints and shrink wrapping each, it took a while. But now the connectors are very easy to access and currently are behind the transmission dipstick. They are just sitting there but I might try and get them clamped to the firewall some how. Before one plugged in right behind the head and it was a pain to reach. I was quite happy with how easily the harness plugged in . There are three plugs and four ground terminals.

[TheSilverBuick]

A few days ago I got the cooling and charging systems installed. I could have probably fire it up right then, but to be safe I want to change the rear fuel filter and do a crank test with a timing light to make sure I don't have the cam sensor 180º out. It should be fine, but I rather check it.



Then when I finally fired the car up it was mostly good. Fired right up and idled well. But it wouldn't rev above 1,200rpm. The tach signal kept dropping out. I re-adjusted the crank sensor and tightened up the clearances to the crank trigger, but it didn't change anything. I did a data log and all the inputs are reading clean, including the tach signal until it dropped out.

Took me a bit longer than anticipated to troubleshoot the problem, but I fixed it. I tried adjusting the signal filters on the MegaSquirt board, no dice, then I swapped sensors, no dice (then put the old one back on), then using my LED test light to check for how the sensor signal was doing when it'd break up and suddenly it would rev cleanly as much as I wanted. Unhooked my test light and back to cut off at 1,200rpm. So I knew it was in my crank sensor wiring and may be my pull-up circuit.

And sure enough, there was the culprit. Re-soldered it back up and it ran like a champ.


Got a video, but almost didn't. The dang fuel problem cropped up again and stranded me on the side of the road three times before I got it back home. I richened it up quite a bit, probably from unknowingly at the time offsetting the fuel starvation issue, so I need to un-do those changes. I'm going to drop the fuel tank tomorrow and check out the pickup and start redoing the whole fuel system.

And the video. I wanted to do a burn out video, but after the fueling issue I didn't.
http://youtu.be/zV01a0cHNUA