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Discussion Starter #1
I’m quickly blown away by the good mechanics who are posting their conversion using Chevy 265 pistons altering piston height, offset pin locations, block decking, angle milling the head, forged connecting rods etc.. oh and don’t forget the fuel injection, sprint manifolds ALL of these performance upgrades look great and I wish I had the bank for even some of the aforementioned. That said, I’m doing a simple 2.0 rebuild. After all would I be that disappointed if I just got a straight Opel 2.0 piston (gapless rings), valve upgrade using the existing hydraulic cam .405/256? Or possibly a OGTS combo cam valve kit? I really don’t know and that’s why I try to listen and learn.

Here’s a suggestion that seems simple (I think) and worth considering. I’m curious when converting to the Chevy valves. Say the 1.72/1.5” combination what’s the recipe for the springs etcetera? The studs, nuts and rocker arms remain stock? Does everything else have to be converted? If so what’s the breakdown?

I have a second head on the shelf that can be fully converted when I do have more money to have it worked over as prescribed by Bob in his excellent street porting a 1.9 post. After I rebuild my block using the good 2.0 pistons and gapless rings (on the #2 ring/second from the top), new chain rails, balanced with whatever else is recommended for a complete restoration on the block, It should be pretty sensible to use that second cylinder head down the road when I can add the other important things to the total package ie intake/exhaust mods. Right now at the risk of some redundancy on my part. Here’s what I have and plan on continuing with for now.
1) Weber 32/36 DGV, AEM Wideband and multiple jetting options,with a pretty comprehensive jetting selection.
2) Stock coil and distributor 00231167-007 I think 1970 and a 00231167-037 maybe 1971-1972? with the Crane XR700 and access to different springs if needed to modify mechanical advance curving. (Hopefully not).
3) I have the stock manifold with a 2” exhaust.

Things decided and to implement at this time:
1) 2.0 stock pistons & pin set, Gapless piston rings
2) Master link timing chain
3) Porting carburetor intake plenum at mounting base to accommodate the 32/36 (currently unmodified)

Things I’m considering:
1) Modified cam sprocket ready to install (see pic) still recommend with 2.0 upgrade for street use?
2) 1.72”/1.5” Chevy valve conversion ? Or stay with All Opel 2.0 valve conversion.
3) Use existing cam .405” lift with .256” duration (using 1.5 as the multiplier for the rocker arm ratio).
Buy the combo cam valve kit from OGTS?, if so what cam would be best? If I do this, it might be economically sensible to get the package 2 liter valves.
?) Last and least I have 2 stock cams, solid and hydraulic ? Re grinding a sensible option?

Keeping in mind what I’m using. I’ve grown attached to the hydraulic lifters. I certainly don’t want to battle detonation or pinging on pump gas, another reason bumping up the compression to high intimidates me. Strictly a daily driver with my GT. I love the winding through the gears up to yellow or redline, don’t know if cam sprocket advancement will change that very much if at all, or if it’s needed?
I hope I’m presenting enough information. I’m sure I’m missing something, if anyone has experience with a similar conversion, guidance and support is most welcome. I really want to plan this well going in and enjoy the process.
 

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There are a bunch of Opelers on this site that have bumped their 1.9 to a 2.0 as the 1.9 is just 1897cc. Using Chevy valves is what I had done recently when I had my 2.0 built, the main thing is, you want to have your machine shop knurl the valve guides for the Chevy valves, or even better, have bronze valve guides installed
 

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Discussion Starter #3
There is a bunch of Opelers on this site that have bumped their 1.9 to a 2.0 as the 1.9 is just 1897cc. Using Chevy valves is what I had done recently when I had my 2.0 built, the main thing is, you want to have your machine shop knurl the valve guides for the Chevy valves, or even better, have bronze valve guides installed
Thanks for the advice I’ll look into the bronze, I just looked at Summit Racing to give me an idea and they have 8 for about $90. I’ll check with the machine shop to see if they stock any on the shelf. I noticed all of the R Bob conversions use the bronze ones too.
 

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I'm no expert. I did my research but had most of the work done for me so I commend you for doing alot yourself. I did the 1.9 to 2.0 as well. Big valves in head & Combo Cam . Just a note the combo cam is a bit loppy . Not sure if you want that or not. Having good luck with the Crane cam 3000 instead of the 700 & PS91 coil. Eliminate the Vaccum advance. Another options are to lighten the flywheel or go to the Chevy S10 or add the 105 amp internally regulated alternator. Really noticed a big difference with the clutch upgrade. More of a medern feel. The 32/36 weber couldn't quite keep up even with all the jetting changes . Went to the 38 & happy with it. More power for sure but has a hard time idling until it gets warm. good luck
 

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Opeler
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Choosing a cam and valve sizes

1.72”/1.5” Chevy valve conversion? Or stay with All Opel 2.0 valve conversion?

Engine - Opel GT - Store | Opel GT Source
2.0L Valves (Pricing on Website):
Intake 42 mm (1.65 in)
Exhaust 36mm (1.42 in)

FYI:
http://www.opelgt.com/forums/opel-engine-performance-modifications/13861-choosing-cam-valve-sizes.html#post130244
http://www.opelgt.com/forums/opel-engine-performance-modifications/13861-choosing-cam-valve-sizes.html#post130258

Hey, I'm certainly not the Opel engine modification expert and I didn't stay in a Holiday Inn last night...
but I'll list what went into the head of my daughters GT.

1.72" Intake valves cut from Manley p/n 11522
1.50" Exhaust valves Manley p/n 11521
Springs Isky p/n 509-D
Retainers Isky p/n 507-STA
7* Valve locks supplied by machine shop
Valve Guides SBI p/n340-1029BR
Valve Stem Seals SBI p/n?
Exhaust Seats SBI p/n SB1562-IN

The head was disassembled, cleaned and magna-fluxed, new guides & ext seats installed and the valve seats were roughed in. I did the unshrouding, guide and porting work and returned the head for final work. Then the machine shop completed the work.

How much you ask? Well, the total for parts plus shipping for the parts I supplied plus the parts and work the machine shop supplied was $595.54 (Note: June 2007 Pricing), taxes included.
Not included in this price is the Cam (Isky OR-66 hyd), cam bearings, and lifters. These I already own from my last engine project.

This head will go onto a 1.9 w/+.040" flat tops with the block milled to bring the pistons to .005" above deck. The cam will be degreed to 2* advanced. The intake has already been street ported with a 32/36 Weber on top ('cause that's what I got). Already in place is a sprint manifold and a nice 2" exhuast sustem. I expect decent power gains and a boost in fuel milage to boot. This should provide good torque over a fairly wide power band and still be able to pull strongly to the factory red line.

More power could be had by upping the intake valve size, but would require more unshrouding which would require more head milling...and so on... The valves springs will allow lifts to ~.460"-.470". So I could have gone with more cam as well. The spring rates will allow safe revs to 7000 at least.

HTH
 

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Opeler
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Tried to edit my previous Post to indicate that Quotation was 2007 pricing - not 2017.
Locked me out of Edit even after a reboot?

Note: Able to EDIT in Internet Explorer, but not Google Chrome.
 

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Über Genius
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$2k is more than enough for a 2.0 build.

You can send an old (but good condition) cam to a regrinding place and have it done for $100. Any profile that will fit on the cam. (I had four done)
OGTS 2.0 piston set. $400 (sale is sometimes less)
Weber carb. Used <$50
Valves $200 (that's a high end)
Head machining, I had mine done, including a surface grind, adding 2.2 valves, for $200
Cam bearings (if you think you need them. $60?
Cylinder boring $150? (I got mine done much cheaper)
Gasket set $150 (or there's a guy in Greece that sells them for $75)

All in all... money adds up. But a 2.0 build will cost as much as you want it to. So, if you want it to cost $2k, spend $2k on it.
 

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Discussion Starter #10
Why the complete circle on the second ring?

Advice read from another R Bob thread
“I would just order a standard Hastings (chrome) full ring set, and order the gapless second ring set from Total Seal. It will save a lot of money compared to getting the entire Total Seal set, and you gain the benefits of the gapless rings still. You just won't use the Hastings second compression rings”.

Second from the top is my interpritation. Reading further on the threads it looks like the regular piston rings can be sent in and converted into gapless rings for about $10 per ring. That said, I certainly would welcome your feedback if you had something different in mind or if my interpretation wasn’t correct. Is there a different way of going gapless on the rings that you have had good results with as well?

http://www.opelgt.com/forums/opel-engine-performance-modifications/519-gapless-piston-rings.html
 

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Just Some Dude in Jersey
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you can buy my 2.0 build with brand new everything, 2.0 High compression pistons, gapless rings, combo cam, chevy valves, list goes on and on.

has literally 20 miles on it.

Under 2k!!

$1999 shipped


www.youtube.com/watch?v=TteVfIFB6TM

If I were you, I'd pounce on Frozen Tater's offer above. Over the past 10 years on this site I have observed that most people's engine redo's at their local shop went wrong. A very high failure rate. There are all sorts of little nuances involved with rebuilding Opel engines that most shops don't know to do. I would tell anyone to go with a proven already built and driven low mileage 2.0 engine in a second. Frozen Turnip did schitt loads of research before his build and it seems like he made one sweet running engine. Buy it, pop it in, start driving.

:yup:
 

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Can Opeler
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I agree. $2000 is a bargain. You will spend that or above that to make your 2.0L once you add in unexpected costs like replacement gasket sets, paint, etc. It is fun to build an Opel engine. I built mine on my own not including boring the cylinders and inserting the pins. I also bought a 1984 2.0L Head instead of refreshing my old one. I’m in at least 2k on my 2.0L and it took me a lot of hours of work.

Unless you are excited to see the guts of a GT engine (like i was). Take FT’s offer. I can vouch for frozen tundra as well. He has sent me a lot of parts in the past.


Sent from my iPhone using Tapatalk
 

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... Reading further on the threads it looks like the regular piston rings can be sent in and converted into gapless rings for about $10 per ring. That said, I certainly would welcome your feedback if you had something different in mind or if my interpretation wasn’t correct. Is there a different way of going gapless on the rings that you have had good results with as well?
If I'm reading your thoughts correctly.
Your not going to be using any power-adders in the build.
If that's true I would move the total seal to the top ring for a touch more compression.

IIRC converting cost was 45 bucks set up fee, 10 or 15 bucks per ring.

Chrome rings will need a smooth hone unlike the cross-hatch for the stock ones.
 

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If I'm reading your thoughts correctly.
Your not going to be using any power-adders in the build.
If that's true I would move the total seal to the top ring for a touch more compression.

IIRC converting cost was 45 bucks set up fee, 10 or 15 bucks per ring.

Chrome rings will need a smooth hone unlike the cross-hatch for the stock ones.
I agree with this. I've installed gapless rings in 1st and 2nd ring configurations. 1st ring for normal applications and 2nd for boosted engines.
 

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Discussion Starter #17
I’ve just ordered the parts, everything but the crank & rod bearings, (possibly cam bearings)? I’ve not had to replace those yet on 2 prior cylinder head rebuilds. They’ll have to wait for the tear down to see what’s needed. I’m going with a straight 2.0 build. I’ve ordered the Mahle pistons rings and pins, I’m not going to bother with the gapless rings, Gil suggests with this piston set I’ll be fine for my application. New master link chain, rails and pump cover. 2.0 valves with OGTS tapered exhaust seats. I’m using existing 405/256 hydraulic grind cam for now. New motor mounts, tranny mount. Complete gasket set for engine, single oil pan gasket. I’m in about $830 for parts so far.
Estimates for machine shop labor varies.
I’m planning on turning the complete long block job over to the machine shop. I’m looking at $800-$1k so far in labor.
Here’s the reason, I’ve got some rust remediation work in and around the engine compartment including driver side hood hinge replacement (typical separation from the body), the battery tray is intact and no severe corrosion underneath but some rescue work should not be delayed there. I’m also installing a new clutch (flywheel resurfaced and complete engine balance), seals and gaskets to replace on the 4 speed a torque tube rebuild and replace pinion seal on the differential. I’ve got everything parts wise pretty much covered mechanically from the engine to the rear end, my goal is to have a good solid 2.0 Opel engine, no more oil drips and eliminate any mechanical failure in the front end to rear hopefully for years to come. All parts are coming in by Wednesday. I like keeping everything Opel, it’s the engine I’ve built my trust in and believe that I’ll get a long life from it if taken care of properly.
I’m taking time to find a good machine shop.
The earliest I would like to get this under way is February.
I’ve been looking into local machine shops. The first one I visited I like, part of the reason is because the owner has worked on the CIH engine several times back in the 80’s, it's a small shop run by a father & son but on the downside they seem a bit overworked, running behind as it were. I asked the son how much a complete engine balance would cost and he said he didn't know because they sub that out and didn't get an answer because he said he was too busy, I felt rushed during both visits. The second one is a guy who appears to be really very good at what he does (35 years plus in the business) and works with a lot of racing mods my main sticking point is that he insists that there is a good chance that my block could have cracks because he has seen good running engines come in all the time with cracked blocks. Why would you approach a first time customer this way? Not the best customer service skills. I’m in no hurry to give him the work at this point.
Next I tried a different approach, I went by and visited with a well established mechanic who used to work on our family cars, been in business or over 20 years and was always reasonable and honest with us and asked him who they send their work out to. I showed him my GT and described what I needed done. He referred me to a couple of machine shops that have been in business for 25 and 35 years and an engine balancing shop. Visiting them will be my next step. Best to take my time and I’m in favor of going by ones that seem best qualified more than once and do some shop talking about the rebuild before handing the job over to them. I’ve simplified the upgrade to have a recipe for success. I not only to be confident that the job will be done right but also want to be treated as I try to treat my own customers at my job.
 

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Über Genius
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I will go out on a limb here and say your block isn't cracked.
I think almost any Opeler would go out on the same limb.

Machining a CIH isn't any different than any other engine with a few small exceptions.

1) The CIH uses a 9mm valve stem. Machine shops often need to buy a tool for that.
2) If the cam bearings are being done, most machine shops don't have experience with them. There are a few tips and tricks they need to know.
3) There's a maximum depth for the valve seats, assuming you will be installing new, hardened, seats (as you should).

Also, it will be easier if you have the valve bosses machined to be even.

If you have the block surface ground, you will, probably, need the front timing cover done as well.
 

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Discussion Starter #19
I will go out on a limb here and say your block isn't cracked.
I think almost any Opeler would go out on the same limb.

Machining a CIH isn't any different than any other engine with a few small exceptions.

1) The CIH uses a 9mm valve stem. Machine shops often need to buy a tool for that.
2) If the cam bearings are being done, most machine shops don't have experience with them. There are a few tips and tricks they need to know.
3) There's a maximum depth for the valve seats, assuming you will be installing new, hardened, seats (as you should).

Also, it will be easier if you have the valve bosses machined to be even.

If you have the block surface ground, you will, probably, need the front timing cover done as well.
My current cranking compression is between 118-120 straight across, I’m really not expecting any surprises. Although anything is possible I suppose.

1)I forgot to mention Gil is also sending new valve guides. Idk if that eliminates the special tool but I think he said it does.
2) A good question to cover with the machine shop if needed. (Hopefully not) I’ve got a good cylinder head on the shelf with good cam bearings but I’m not sure how bad the pitting is until I clean it up. Maybe some fine Emory cloth will reveal how deeply pitted they are. The clearance was good, the head was good before it was dismantled 20 years ago.
3) the exhaust seats are coming in from OGTS I’m assuming that for the machine shop if should be pretty straight forward. Idk about the intake seats? So any further advice on that would be great to know. As mentioned the 2.0 valve set is coming from OGTS.

Could you please elaborate on where the the valve bosses are located? Not being a mechanic I’m completely lost on that although I’ve heard the term used before. Thank you in advance!
 
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