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It lives!

Roller camshaft engine has been fired up!

I had to make new rear brake lines and install new rear axles and brakes on the test vehicle, so it was awhile before I could drive the test car. Drove me nuts having started the car then having to wait a few hours to drive it!

First comment: It needs more fuel, a lot more fuel. The new roller cam is far more aggressive than the old hydraulic cam that came out, and now the car has two REALLY bad flat-spots under acceleration, and some slight popping out the tailpipe. Will bring box of jets tomorrow to try to get it in the ballpark.

Second comment: pulls like an MF at 6k, even with the lean A/F mixture. Didn't want to push the rpms however.....

Third comment: Engine cranks over like it has no spark plugs in it! There's quite obviously a LOT less friction happening in the engine.

Fourth comment: Will likely have to recurve distributor to get best performance, the new cam has 248 degrees duration @ .050", and will need about 15-18 degrees BTDC @ 1200 rpm idle. Current curve would put total timing at 40-43, which is BAD. And less initial timing hurts throttle response.

Pictures of installation to follow.

RollerBob
 

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This was one of the issues I had to deal with when using the roller cam valve springs on a 2.4 (or 2.2) head. The exhaust spring seats do not use the OEM exhaust rotators when using the new 1.25" diameter roller cam valve springs. So, a 'shim' was needed to bring the height in line with the intake spring seats.
 

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The solution was a custom hardened steel spring seat insert that's .270" thick. A thinner .030" spring shim was inserted beneath the custom spring seat to bring the final spring height to the correct number. The intake springs required only a single .030" shim.
 

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Roller cam, lifters, and lifter sleeves in place. It was a major PITA to align the rollers correctly, but all is well now.
 

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Rocker arms installed and adjusted. I ended up setting the valve lash at .016" intake and .018" exhaust. But with the roller rockers, the self-aligning roller at the valve stem is very narrow, and a typical feeler gauge would not fit. I measured the lash at the lifter side, but had to divide the listed lash spec by the rocker ratio (1.557) to get the lash measurement at the lifter side. This worked out to .010" intake and .0115" exhaust (I used .012"). There is some discernable valvetrain noise, but no more than any performance solid lifter cam.
 

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I also threw a Cam Effects stud girdle on the head. Valve spring pressures at full valve lift are at around 380 lbs, so I wanted to minimize the stud flexing by using the stud girdle.
 

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I didn't get to finish everything. I did go up two main jet sizes on the main jets, and reduced the power valve from 10.5" to 9.5" (idle vacuum is 11.5"). The power valve change made the biggest difference, the power valve was 'dumping' the fuel too early previously. I left the ignition timing 'as is', no time to get to it. However, I turned it up as high as possible initially without running into detonation.

As it turns out, there were issues with one lifter sleeve moving. Tried resecuring it, it moved again, and again.....finally changed the one sleeve and lifter altogether, and it still moved. So I ended up drilling the sleeve so the set-screw physically inserts into the sleeve. I secured it with high strength Locktite rather than the medium strength stuff I used before (but ironically none of the other sleeves moves???). The car owner had to head home yesterday, so it was left assembled, but not tested. I wanted the Locktite to cure 24 hours with no oil contamination before testing again.

We did get to drive it on the road yesterday, the car definitely has a lot more power than with the old camshaft. In fact you have to be careful in the lower gears coming out of corners, even with a limited slip and 15" tires the car breaks the tires loose easily.

Have not revved it above 7000 rpms yet. Besides the fear of the lifter sleeve moving again, I was afraid to rev it hard because it accelerates so quickly from 5k-7k it's hard to react....so a rev limiter will need to be installed before testing the threshold of rpm capability. We'll creep up the rpms with the rev limiter rather than risking revving a 2.4 to 8k by mistake.

Have decided to go with a stand-alone ECU and throttle bodies on this engine, it will make more power still, and we can tune for perfect throttle response.

Bob
 

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Good news! The last tweak to the lifter sleeve worked, the lifter sleeve is holding strong. The car goes like hell, it's more noticeable in the upper gears than the lower gears ironically. In fact, the issue at hand seems to be trying to find a big enough road to get a full speed test, it's pulling hard at 100 mph in 3rd gear.....

Can't wait for the programmable FI now!

Bob
 

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If I can get another cam and lifters from the manufacturer, yes, I intend to use this setup.

Bob
 

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way cool Bob i got a big grin just reading you posts

how about a recap of the motor and the setup before and after

most of us could never get a setup like that but its way cool to read about

good job thanks.

David
 

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Dave, the engine is a 2.4 litre bored to a 2.5 (97 mm bore). It has ARP rod bolts, and forged pistons (10.6:1 compression). Block has been o-ringed and it uses a copper head gasket. The head is a 2.4 head, with 1.94" intake valves, and 1.60" exhaust valves. Full porting done, flows 148 cfm @ .500" lift on the intake, and 117 cfm exhaust @ .500" lift, measured at 10" of water on my flowbench. It uses a 2.4 exhaust manifold with a 2.5" stainless exhaust system and Borla mufflers. The intake manifold has been cut open, welded, and ported, and modified to fit the 2.4 head, then has an adapter for a 500 cfm Holley 2-bbl. It uses a European distributor with Bosch electronic pickup, and a Jacobs ignition with Ultra-coil. Plugs are NGK, gapped at .045".

The old cam was a hydraulic profile, with .465" intake lift/.447" exhaust lift, 222 intake/218 exhaust duration @ .050". Lobe separation 112 degrees. The new roller cam is .498" lift with 248 degrees of duration @ .050", and also with 112 degree lobe separation. I'm using my old design of roller rocker arms, with a new Cam Effects stud girdle (copy of my old design).

That's about it. The engine will be getting a stand-alone programmable FI system, with a custom intake manifold I will fabricate that uses two stock 1975 Opel TB's, with one feeding each pair of ports. So there will be a small plenum effect with this design. I will also be fabricating a header for this engine later on, when it gets removed from the current 1975 wagon (weighs 2500 lbs with 3.67 axle ratio), and will swap it into a 1971 Ascona (2013 lbs with 4.22 axle).

Bob
 

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Thats a pretty cool idea for the manifold. It should literally be a straight shot from the port to throttle body which should make it flow well and be easy to fabricate.
Rectangular runners? Is this in the plan for this month?

-Travis
 

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I already modified the TB's, removed the old 'TPS' switches, filled the vacuum holes, cut off the water lines, etc. Been thinking about this for a while actually.

The intake will start round and taper down to two semi-rectangular ports, very easy to do with sheetmetal, and I already have the steel flanges to fit a 2.2/2.4 head. I'm just gonna make the intakes from steel, and have them ceramic coated.

Not in this month's work log Travis, gotta get back onto the GT-4 Manta. Although I'm gonna miss the hillclimb season, I'd love to at least get that car out onto the racetrack once this year.

Bob
 

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Those head flow numbers are really impressive.

Do you have the facilities to post a sound byte of the car running?
 

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Actually I was thinking of digitally videotaping the car doing a smokey burnout at 7000 rpms and then posting a link to it, but the reality of the situation is that I should stick to cars...... computers aren't my bag.

Bob
'compewtur eliterate'
 

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madhatterpdc said:
Those head flow numbers are really impressive.
Sorry, missed this part before. The 2.2 and 2.4 heads flow really well compared to the stock 1.9 and 2.0 heads, especially with larger valves and porting. Still, they're better suited to bigger displacement Opel engines, or really high-revving smaller engines, as the intake ports are quite a big bigger (and raised)than those of a 1.9 or 2.0 head. And the 2.4 has very large exhaust ports, I don't recommend them on anything but a 2.4 litre or larger engine.

Some stock Opel airflow numbers and potential airflow numbers I've attained:

1.9 intake: 89 cfm.....128-130 attainable (with a lot of work)
1.9 exhaust: 67 cfm.....112-115 attainable

2.0 intake: 96 cfm.....120-124 attainable
2.0 exhaust: 76 cfm.....95-105 attainable

2.2 intake: 122 cfm.....145-152 attainable
2.2 exhaust: 77 cfm.....97-112 attainable (with a lot of work)

2.4 intake: 110 intake.....142-148 attainable
2.4 exhaust: 93 cfm.....110-117 attainable

Bob
 

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Oh yea....this roller cam engine is making some torque ! The owner called me today, he ripped the torque tube side mounts right off, and shredded the torque tube donut when shifting from 1st to 2nd gear. I love it.....

Bob
 
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