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2.0 roller rocket finish

6255 Views 64 Replies 9 Participants Last post by  nobody
I've been busier than ever and instead of scattering various threads about, If it's ok With you all I decided to put up a newer thread that included some of the getting back to regular gas and a roller install that is coming right up. To be honest I do use the threads as a reference to myself and it allows me to look back and see where I could have done something different or where I found such a great idea.

A quick summary of the last couple of days include the removal and replacement of the back glass. I found and procured a fresh billet cam that has me pretty happy, ok alot of luck on that one. I welded in the plate for the passenger side retractor seat belt and did some interior finish work. I also removed the stock fan and shroud without removing the radiator and installed an electric one from I believe an early Honda. I also did the remote battery mount and tried it all out.

I was told that tomorrow or the next day the cam may ship so I'll be doing this a bit quicker than expected.

If this is ok with you all I'd like to keep up on the documentation, if it is, then I'll work on some pics of the most recent mods and I suppose if the old thread is salvaged they could be merged?
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Of course, you're right Bob, it just goes to show you how often I've looked at the Opel crank pulleys, since I pulled the 1.9 out of the GT over 2 years ago. :D BTW, a really quick way to notch the pulley is with a Dremel and their cutoff wheel, Part #409, it is about 1/16 thick and will slice through steel fairly easily. but requires a steady hand, and will leave a very clean notch. And again, thanx for setting me straight on something that I should have checked a bit more closely before I "opened foot, insert mouth". :D
I did notch them all but just continued the lines out some to show the idea. A degree wheel would be nice. On this motor with the twins and cold air intake just getting your hand on the flywheel timing mark is a trick, forget about seeing it. I wonder if a round degree wheel would stick to the front angled face of the pulley? I guess you could tap the front bolt and put something there? Just thinking out loud.
Well I have been back about a day or so and the parts are finally arriving. The first pic is a look at the lobes on that fresh billet next to a stock one. Next is those really pretty solid lifters.

ok the pics are backwards from the text...
Just for those that want to see the numbers I'm posting the cam card on that monstreous cam. I'm also posting a pick of a varience between a 75 breaker plate and an earlier one. Note the difference in the advance retard attachment point being moved from one side to the other.
I was doing some planing of this weekends work in my head today and it just dawned on me that the timing gear will be in the way of slipping the old cam out and the new one in. I remember years ago jacking up the front of the motor to clear the radiator support to pull one but can't remember how I got past the gear. Any suggestions or ideas would be nice.
Lets see... Pure speculation here... First off, put the engine at TDC with No. 4 cyl firing. Then the big thing would be to make sure the timing chain does not slip off the crank gear. You could remove the chain tensioner to give you some slack. Then use some bailing wire to tie off both sides of the chain as it comes through the head or run some wire through the top of the chain up to the hood and then let the upper part of the chain slack and remove the gear. With a new cam you will be starting the valve timing from scratch so if the crank doesn't move you should be able to set the upper end fairly easily.
If you use a cam chain with a joining link then the chain can simply be broken at the joint and the upper gear easily removed. Wire up each end of the chain so it does not disappear down into the front cover ........
This makes it far easier to replace a cam chain too as the new one can be linked to the end of the old one and fed down through the front cover. However DON'T rotate the motor while the cam gear is disconnected as the pistons and open valves will "meet" each other with life altering consequences!
Ok I've hit a few minor snags in the plan so far. To start I noticed that the distributor housing for the 69 doesn't have a cut out for the notch to align the cap on it. I overcame this one by using a 72 distributor body with a 69 advance unit and a 73 shaft. I used one spring from the 69 and 1 from the 75. It has an early year breaker plate so I think I've scavenged pretty much every year I have parts from.

I was concerned about valve spring bind and Jim had the idea to test the rollers and cam in another head not on the 2.0. I picked a 73 head that just had springs and valves similar to what is in the 2.0. To make a long story short I'll be pulling the head off of the 2.0 to fix a spring bind issue on the exhausts. The intakes were ok with the new .4546 lift but the stock exhausts were in full bind. I think I'll change out the exhaust to use intake springs and eliminate a few items to get the spacing right. I'll try it on this other head first and just duplicate it on the head for the 2.0.
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Ok the intake springs being used on the exhaust side looks to be just the ticket. I've been trying a few combinations after removing the rotator and if I use the dimpled spring retainer it puts me just a bit on the high side of spring compression limits. The intakes are closer to bind but still ok.

I did need the break from this project, if I would have found out last week that the head had to come back off. I don't believe my reaction would have been very pleasant. I'm not overjoyed at the prospect but I have a renewed patience to keep at it.
You could always use one of those air chuck and valve spring compressor set ups to change the valve springs with the head on.

But then you are also changing out the cam so in the time it would take to raise the engine and pull the hood off, you could have the head sitting on a bench. ;)
All righty then, I'm in a POR kinda mood and I just got a good look at a few pieces that I really liked. I think It's running a little bit rich so I'll do the backwards thing and add cam before I mess with the jets.

I taped the motor so I can hear any differences after this upgrade and it was kinda nice working with a warm motor. Yes it's show time and the rollers are next on the to do list.

POR to me is Press On Regardless.
Well the head has been off long enough. I replaced the questionable valve springs and adjusted and checked them all. Feeler guage in these pics are .020. I checked them all and set all the valves off of the motor.
I"m running in the cam as I type this. It just speaks volumes of ya never know what's under the hood. it looks pretty stock to me.....but I know better.

It gained 1000 RPM just upon fire up and after 20 minutes I toned it down to around 1100. It's running a bit hot but is cooling off, that was expected.
Hey, nice little purple things on top of your motor...what are they called??..roller rockers...nice color, I bet they are great quality. Thanks for the exposure. samdog
I was done letting it run in the new cam when my Dad came by. Yes I pulled the cover off just to show them off a bit. I don't think he got all that was involved but my daughter understands it all and likes the little purple bits on the car, she informed him of the purple upgrade.

Time to think about a clear cover for these.
Ok I have few ideas and ways to go now and I'll see what this motor likes. I have some jetting options and some timing options yet to be tried. I am still thinking of the 30 mm choke tubes and going to the F11 emulsions. My thinking on this is a bit faster transition and bringing back some of the low end I gave up with the cam. I have a set of 115 mains that to me are way to lean for the 11:1 but did aquire some 170 airs and carriers that were needed to get the DCOMs to be more compatible with air correctors here in the States. My plan is the F11s and the 170 airs VS the 160s. Putting in the 45 F9 idles and seeing how it acts. Mind you this is still running 138 mains and 32 chokes right now. Or should I do the distributor first before messing with any jetting? Any input on this for the twins would be appreciated.
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Getting the ignition timing and advance curve locked in and the rocker clearance locked in are "musts" before fine tuning the carbs as they are fundamental to performance. No use getting the carbs "right" for other
settings that are not the ones that are going to be used in the final set-up!
Some of that wet weather has moved inland so I have been playing and just had to share this pic.
1.9L - Rebirth

"Somebody" has another motor inside on the parquet flooring!

There are Irmschers hidden behind those Webers I should think ..... and I recognise the studs and nuts on the Pommie exhaust manifold!

That will make a super setup for the 9:1 LO-comp (relatively speaking!) motor.
I'll explain a bit of those pieces in that pic. Right carb is a DCOM in mid rebuild and left one is a DCOE that I just got. The exhaust is a 2.4 Vauxhall and yes there are shorty Irmshers in there too. Ok it is bolted to a 73 head placed on an early block just to see if it would fit. No I'd never run it with that missmatch but it does look cool. I wondered if that 2.4 would work with twins and it fits nicely.
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