CIH Turbo EFI by RallyBob

[RallyBob]

After mucho time off from this project, I again picked up the pieces and tried to get something done. Well, thanks to a long visit from Mr. Murphy today, things progressed as well as can be expected.

For starters, I got out the eight valves, the eight valve seals, and the seven retainers to assemble the head. Seven? Yup, one is missing and nowhere to be found. Doesn't matter anyway, I can't find my valve spring shims....

Okay, so I'll forget about assembling the head, and instead finish up the shortblock accessories. "Oh Mr. Murphy, so nice to see you again." I had that damn oil pan on and off 4 times, each time I had to to a little bit of grinding or clearancing. I had to cut some off the dipstick tube to clear one connecting rod. I had to trim one oil pan baffle bolt to clear a main cap. Of course each time I needed to clean the oil pan, reassemble it, and test fit it again. Yeesh. So for those of you who think I always get things right, I say 'HA!'. What a day...

One of the biggest issues was the pickup tube bracket. I used a late-model bracket which fits the newer 2.4 engines, and it interfered with EVERYTHING.
Live and learn.

[RallyBob]

In order to ease some of my pain from the unproductive day, I decided to at least bolt some of the accessories to the shortblock. At least now it looks like it's coming together, and gives me some incentive to finish it soon.

[madhatterpdc]

Two things, that starter sure does look purty

And why not an adjustable cam gear? It would seem that with so much custom stuff going on that being able to tweak the cam timing would be key (yeah, that was probably the worst pun ever).

[ConreroGT]

When you oblong the holes on the timeing gear, do you do (add) anything special with the bolts to prevent slipping? Or is it not an issue?

[namba209]

Bob, thanx for inviting A. Murphy up to your neck of the woods. Maybe it was getting too hot here in SoCal for his liking, and he traveled to the Northeast. I was thinking about pulling the motor/tranny on Willit?, but new puppies put that on hold for a week, maybe that's why he left, nothing here for him to screw up, he said, tongue in cheek.

Seriously, your work on that engine is, as usual, a work of art. If only I could do so well. You've raised the bar, again, for us to work up to.

[baz]

Originally Posted by ConreroGT When you oblong the holes on the timeing gear, do you do (add) anything special with the bolts to prevent slipping? Or is it not an issue?

they use offset hole inserts ,if you have a look here http://opelgt.com/forums/showthread....ght=cam+timing
it covered

[RallyBob]

Much better day today, uncle Murphy decided to stay away. I screwed the rocker studs into the head, making sure to not only oil the threads, but also to put a dab of oil on the tapered area that contacts the stud hole. This is critical to achieving proper torque. No loctite is to be used here! You don't want to clog the oil passages to the rocker arms.

Next step was to install the valve seals. I'm using a metal shielded viton positive valve seal. My method to install them requires a special 'tool'....namely a 12mm 12-point socket with an extension. I very carefully tapped the seals onto the guides with a hammer and this tool.

A visit to my friend's machine shop gave me a chance to test the valve springs for spring rate on his spring tester. In order to get my required spring rate, I needed to shim the intake springs by .015" and the exhaust side by .030". Total rate at max lift (.440" after valve lash) is 235 lbs on the intake and 232 on the exhaust side. Next a bit of synthetic grease is spread on the valve stems and they are installed in their respective guides.

[RallyBob]

First pic: 1.85"/1.50" valves installed in the head.

Next was the valve cover studs. I use a 304 stainless socket set screw, 6mm x 1.00 pitch x 40mm long. A dab of loctite on the end, and they're tightened by hand snugly to the head.

I then fitted the polylocks to the rocker studs, and tightened the set-screws against the studs. This allowed me to use a torque wrench to tighten all the rocker studs to spec, 29 ft. lbs.

Onward to the block, a brass drain petcock is fitted to the block at the coolant drain hole. The actual block thread is 14mm x 1.5 pitch metric pipe thread. But 1/4 NPT is nearly a perfect fit to this thread pitch, so a standard hardware store $1.79 fitting was used, and I glued it/sealed it in place with a dab of JB weld.

[RallyBob]

A few more pieces were installed onto the timing cover, namely the oil adapter and the oil pump itself. The oil pump gears were first installed dry in the timing cover housing and gear protrusion was measured to be .003". With a dry gasket in place and the pump cover fitted, the pump was turned over with a screwdriver to be sure there was no binding. I then took it back apart, and packed the pump housing and gears with synthetic grease, and reapplied the gasket and pump cover, torquing to spec evenly in a criss-cross pattern. A few twists of the adjustable pressure regulator will increase pressure by about 15 psi, so I hope to have a peak pressure of 70-75 psi.

One of my pet peeves with Opel engines is the crappy stock timing mark on the flywheel. I make this easier to read and to adjust by marking the crank pulley and using the timing cover as a reference. First, the #1 piston is raised to exact TDC (measured with a dial indicator), and the crank pulley is marked relative to the large timing mark on the timing cover. Then I remove the pulley, laying it on a degree wheel, carefully centering it and aligning the mark I made on it with '0' on the degree wheel. Noting the direction of rotation, I mark the pulley in 5 degree increments, stopping at 40 degrees. There is really no reason to ever go beyond 40 degrees, and in fact it is there only as a reference since timing will never go that high. On a turbo engine such as this, total timing will be more on the order of 22-25 degrees, so even 30 degrees is somewhat redundant!

With a file, small notches are made in the edges of the pulley coinciding with the ink marks I made on the pulley. After the pulley is powdercoated, I'll be taking some contrasting paint and marking the hash marks for ease of identification when timing the engine later on.

[RallyBob]

More done!

I finally got around to bolting the head onto the shortblock today. Here I have layed out the supplies I used, namely the 2.0 litre head gasket, Permatex gasket sealer for the timing cover area, Hylomar sealer for the gasket itself, the water passage o-ring seal, and a set of cleaned head bolts.
The head gasket was a near-perfect fit, only requiring some trimming at the oil drain hole to ensure proper alignment. Prior to fitting the head gasket to the shortblock, I trimmed off the excess timing cover gasket material with a razor blade to ensure a good seal.

I then used some gasket sealer on the top of the timing cover, and on both sides of the head gasket at the timing cover contact area. This was allowed to cure for about 15 minutes, then Hylomar sealer was applied to both sides of the head gasket and the head torqued in place in increments of 25/40/55/70/75 ft lbs of torque.

Next step after putting the head in place was to attach the timing gear to the camshaft, and tighten the hydraulic chain tensioner in place. I followed up by degreeing in the cam. I had taken a guesstimate and initially placed a 2 degree offset bushing into the modified upper cam gear. After checking the opening and closing times of the cam @ .050" tappet rise, it ended up with the intake centerline at 112 degrees, and the lobe separation angle ended up being 112.375 degrees, for a whopping .375 degree of advance. Good enough!

[RallyBob]

More inaccuracy here. A test fit of the water pump pulley showed it is about 1/16" inward from the crank pulley. I'll end up making a 1/16" shim to correct this matter.

Also note the timing mark on the flywheel. Not really that close, is it? The front pulley has been indexed via the #1 piston TDC location, but it doesn't coincide with the mark on the aftermarket flywheel. No biggie, since I always time the ignition off the crank pulley anyway, but worth mentioning. I never trust the flywheel timing mark!

[RallyBob]

Now the fun begins! This is basically the final mock-up step before the engine goes into the car. I started bolting on all the accessories: distributor, cam cover plates, spark plugs (gapped at .028"), intake manifold, exhaust manifold, turbocharger....

From here most of the final plumbing can be performed. I ran -4 teflon oil line from the timing cover to the turbo oil inlet. There will be -10 line run for the turbo oil drain to the fitting I previously welded to the oil pan. Coolant lines have yet to be run, and there will be various sensors fitted to the intake manifold, the inlet pipe, and the thermostat housing for feedback to the ECU.

[simplemind7]

wow, that engine looks amazing bob, great work... now i want a turbo

i see you're predicting 300hp and using a getreg 240... are you sure it will hold up?

[RallyBob]

Originally Posted by simplemind7 i see you're predicting 300hp and using a getreg 240... are you sure it will hold up?

This car is getting a 265 Getrag. I thought about it a bit, and it's one less thing to replace later on!

I just ordered the custom clutch setup for it on Friday...it uses the Unorthodox Racing aluminum flywheel with a 9.125" Chevy S-10 pressure plate, but with a custom 9.125" semi-metallic disc with the appropriate 1.125" x 10 spline to fit the Getrag 265.

Getrag 240's use the same spline as the 4-speeds, which is 1" x 14.

Right now the clutch and the special fuel rail/injector machining bit are the two things holding up the engine from being installed. So in the meantime I mocked everything up on the engine stand and have plumbed most of the oil/coolant/vacuum lines on the stand. I may even try to make the exhaust downpipe off the turbo while I'm waiting for parts. I will get some final powdercoating done in the meantime as well.

Bob

[simplemind7]

how much power can a 240 and a 265 take before it gets ugly?

i've been trying to find this out because i'm sending out the car for paint in about a week, which means i need a new project to work on at home... and i have that spare engine sitting around... so i'm looking into tranny options to see what power i want to get out of the engine without having to spend a fortune on a tranny

[RallyBob]

Originally Posted by simplemind7 how much power can a 240 and a 265 take before it gets ugly?

I don't know the actual torque rating of a 240 Getrag, but I've had a few lose gears with only 150-160 hp, and after 200 hp there's not much hope of one staying together too long if you're a spirited driver.

The torque rating of the Getrag 265 is supposedly 350-360 lb ft, so it should last quite a while for most any 4 and 6 cylinder engines. I've heard of a few of these with 400-500 hp turbo engines and they seem to do okay. Apparently it's also a popular tranny to swap into Jaguars as well.

The turbo in this car is good for about 380 wheel hp maxed out, but I doubt we'll go that high with the pistons in there now. I'd like to start at about 230-240 whp and shoot for 320 whp or so reliably, at which point I suspect there would be around 260-270 lb ft of torque. I've got the injectors and fuel pump to feed it now, so it should be safe if the mapping goes well.

Bob

[RallyBob]

Here's a look at the fuel rail options I had. As you may recall, I started out with the tubular steel fabicated fuel rail to be used with OEM-style hose barb injectors. When I upgraded to modern top and bottom o-ring style injectors, I had to buy some aluminum fuel rail extrusion, which was sized for -6AN fuel line. After some thought, I changed my mind (once again) and ordered some larger diameter fuel rail, which will accept -10AN fuel line fittings. A larger ID fuel rail will dampen fuel line pulsations more effectively than a smaller ID rail. So we're good for sustained high power runs now.

I got all my plumbing figured out today, and of course I need to make another parts order for more AN fittings and lines to complete it. Getting there!