monza 3l moter same as a 2.8 commodore moter???

[muscle_car_man]

hey

any information would be great regarding this matter!i have just recently purchased an opel commodore,4 door,2.8 injected 4 speed manual.i was just wondering if these motors are the same or (how similar)they are to my 86 opel monza 3l.last question,are the 4 speed manuals any good?

cheers michael

[heimue]

The straight-6 CIH Opel motors are all the same family, from the 2.6 to 3.0 Liter versions. They only have a different displacement, but I don't know whether its bore or stroke differences. They are mechanically interchangeable (motor mounts, clutch, gear box...).
This excludes the later 3.0 DOHC motors (Senator B/Omega A), they have a different block/head.
The manual transmissions are ok if your motor is close to stock. I wrecked two automatic transmissions on straight-6 motors back in Germany, but never had any trouble with a 4-speed conversion in an Admiral. Of course, a 5-speed Getrag 265 is unbeatable in this league.

Dieter

[GoinManta]

Going completely off memory.. So forgive me if I am wrong.

Main difference in 2.6 to 3.0L should be in the bore.. Dont know a lot about 2.6L but believe if its like a 1.7L then the head camber will be smaller and bore the same or it could be like a 1.9L head on a 1.5L Block and the head is the same the bore slighly smaller. But the 2.8L and 3.0L are about the same head.. different bore.

The 2.8L was basically a carb motor. Although some 2.8L Commodore B GSE models used early L-Jet Bosch injection in the mid- 70s. Came with both single carb 2 barrel Zenith Carbs (Commodore B GS), Dual Solex Setups (Commodore A GSE and Manta TE2800) and possibly other combinations (Not familar with NON-Commodore applications) if memory serves.

The 3.0L (12V) used Bosch early L-Jet injection to 1984 and the later (Non-resistance injectors) L-jet to about 1989.

The 3.0L (24V) used Bosch K-Jet (Senator and Monza GSE Motor I believe)

The 3.9L (Bitter motor) was a stroked 2.8L.. yes a stroked 2.8L not 3.0L, not sure why but thats what I was told. I think its because they bored the 2.8L Instead of the 3.0L because of smaller water passages allowed larger boring or something. It used the later L-Jet and had unique pistons, crank and rods.

Thats what I remember from when I had my Bitter and rebuilt its motors.

[GTJIM]

Answer from someone in the same city as you!

The difference between the 2.8L and 3.0L six-cylinder motors is much the same as between 1.9L and 2.0L four-cylinder motors (1.9L x 1 1/2 = 2.8L and 2.0L X 1 1/2 = 3.0L). The bore size only is difference - 2.8L is 92mm bore and 3.0L is 95mm bore. The outer dimensions of the cylinder block are identical and everything bolts up - the only differences can be the intake ports position - like 1.9/2.0L motors and 2.2/2.4L - depending if one motor is 1983 or earlier and the other 1984 or later.
You can probably bore a 2.8L out to 3.0L just by using 3.0L pistons - or Chevy pistons ... just like the 1.9L four-cylinder motor ... and fit Chevy valves into the head ... the same.

1.9L four-cylinder pistons can be used too - they are 93mm STD - so are a nice 'first oversize' for the 2.8L six ...

[heimue]

Originally Posted by GoinManta The 3.0L (24V) used Bosch K-Jet (Senator and Monza GSE Motor I believe)

The 3.0-24V (introduced in 1989) was not available in the Monza or the Senator A (1983-87), only in the later Senator B (1987-94).

The largest engine in the Monza was the 3.0-12V with 180HP (depending on the market, the HP number might be slightly different).

Dieter

[tekenaar]

Originally Posted by GTJIM Answer from someone in the same city as you! The difference between the 2.8L and 3.0L six-cylinder motors is much the same as between 1.9L and 2.0L four-cylinder motors (1.9L x 1 1/2 = 2.8L and 2.0L X 1 1/2 = 3.0L). The bore size only is difference - 2.8L is 93mm bore and 3.0L is 95mm bore. The outer dimensions of the cylinder block are identical and everything bolts up - the only differences can be the intake ports position - like 1.9/2.0L motors and 2.2/2.4L - depending if one motor is 1983 or earlier and the other 1984 or later. You can probably bore a 2.8L out to 3.0L just by using 3.0L pistons - or Chevy pistons ... just like the 1.9L four-cylinder motor ... and fit Chevy valves into the head ... the same.

Opel 6-cyl CIH: 2.6 (88.8mm x 69.8mm = 2594cc) ; 2.8 (92mm x 69.8mm = 2784cc) ; 3.0 (95mm x 69.8mm = 2969cc) ; Bitter/Mantzel 3.9 (95mm x 90.5mm = 3849cc)

Opel 4-cyl CIH: 1.5 (82.5mm x 69.8mm = 1492cc) ; 1.7 (88mm x 69.8mm = 1698cc) ; 1.9 (93mm x 69.8mm = 1897cc) ; 2.0 (95mm x 69.8mm = 1979cc) ; 2.2 (95mm x 77.5mm = 2197cc) ; 2.4 (95mm x 85mm = 2410cc)

. . . all Opel CIH (4/6) engines have used common bores of 82.5mm (1.5), 88mm (1.7/2.6), 92mm (2.8), 93mm (1.9) and 95mm (2.0/2.2/2.4) respectively and all CIH (4/6) engines, except the 2.2 (77.5mm), 2.4 (85mm) and the Bitter/Mantzel 3.9 (90.5mm), used a stroke of 69.8mm.

[RallyBob]

Originally Posted by tekenaar Opel 6-cyl CIH: 2.6 (88mm x 69.8mm = 2547cc) ; 2.8 (92mm x 69.8mm = 2784cc) ; 3.0 (95mm x 69.8mm = 2969cc) ; Bitter/Mantzel 3.9 (95mm x 90.5mm = 3849cc)

Otto, what about the 2.5 litre straight six? I believe that was in the early Commodores and available w/twin carbs.

[2 Fast 4 U]

2.2 litre straight six 82.5 x 69.8 = 2239 cc
2.5 litre straight six 87.0 x 69.8 = 2490 cc
2.6 litre straight six 88.8 x 69.8 = 2594 cc [sorry Otto]

1.6 litre straight four 85.0 x 69.8 = 1584 cc

[RallyBob]

Originally Posted by 2 Fast 4 U 2.2 litre straight six 82.5 x 69.8 = 2239 cc 2.5 litre straight six 87.0 x 69.8 = 2490 cc 2.6 litre straight six 88.8 x 69.8 = 2594 cc [sorry Otto] 1.6 litre straight four 85.0 x 69.8 = 1584 cc

Thanks!

Now we need to put all these bore/stroke/displacements and HP figures onto one page for future reference, and then lock it out!

[spamseptictank]

This may be off-topic, and I may incur the wrath of the mods, but I would like to complement you guys on your knowledge of Opels.
I continue to marvel at the wealth of knowledge contained in your heads and others who have posted here. I rarely need to ask questions. I find out all I need to know by reading your posts.
Thank you for sharing and helping.
Thanks to Gary, too, for doing this site.

[Hiro]

Originally Posted by muscle_car_man hey any information would be great regarding this matter!i have just recently purchased an opel commodore,4 door,2.8 injected 4 speed manual.i was just wondering if these motors are the same or (how similar)they are to my 86 opel monza 3l.last question,are the 4 speed manuals any good? cheers michael

well if your car is like one of mine (Commodore B GSE),
this 28E CIH is quite of a weird bird among the CIH family:
bore is only 92mm this makes a PITA to find parts like rings,
injection is the old type D Jetronic (nothing to do with the later L/LE),
the head is very special with injectors directly mounted on the head,
so inlet ports are a few mm lower than a casual 1.9/2.0 head,
manifold gasket is therefore specific.
I just love this car (I have 5 of these),
but consider to collect lots of parts to be on the safe side,
or convert it to a complete 30E setup (very easy).
HTH,
Hiro

[Hiro]

Originally Posted by GTJIM Answer from someone in the same city as you! The difference between the 2.8L and 3.0L six-cylinder motors is much the same as between 1.9L and 2.0L four-cylinder motors (1.9L x 1 1/2 = 2.8L and 2.0L X 1 1/2 = 3.0L). The bore size only is difference - 2.8L is 93mm bore and 3.0L is 95mm bore. The outer dimensions of the cylinder block are identical and everything bolts up - the only differences can be the intake ports position - like 1.9/2.0L motors and 2.2/2.4L - depending if one motor is 1983 or earlier and the other 1984 or later. You can probably bore a 2.8L out to 3.0L just by using 3.0L pistons - or Chevy pistons ... just like the 1.9L four-cylinder motor ... and fit Chevy valves into the head ... the same.

the 28E is very different from the carb versions 28S/28H:
head, camshaft, exhaust valves, pistons are specific.
IMO the weirdest part of the 28E is the distributor:
it contains a second set of twin points that triggers the injectors,
better not have any problem with this distributor,
because it's very rare even on Ebay.de!
HTH,
Hiro

more infos on the D Jet here (french, sorry!):
DJectronic

[2 Fast 4 U]

Originally Posted by 2 Fast 4 U 2.2 litre straight six 82.5 x 69.8 = 2239 cc 2.5 litre straight six 87.0 x 69.8 = 2490 cc 2.6 litre straight six 88.8 x 69.8 = 2594 cc [sorry Otto] 1.6 litre straight four 85.0 x 69.8 = 1584 cc

I found an other engine:

3.6 litre straight six 95.0 x 85.0 = 3590 cc

[GoinManta]

Originally Posted by Hiro well if your car is like one of mine (Commodore B GSE)...... but consider to collect lots of parts to be on the safe side, or convert it to a complete 30E setup (very easy). HTH, Hiro

You wouldnt be able to find a nicely restored GSE Commodore B for sale in the area.. ? One of the cars I was thinking of finding in europe to import.

Also FYI.. Chuck Jordan who designed the Commodore B Is looking for one to import as well.. I had one, but Todd at Opels Unlimited has it now and its in really bad shape. Irony is that I brought it to California to save it because I couldnt find parts at the time and didnt want it to rust.

[muscle_car_man]

thanx a lot for all your help and extreme knowledge of opels, i'll keep you guys informed of how my progress goes!
cheers

[tekenaar]

Originally Posted by 2 Fast 4 U 2.2 litre straight six 82.5 x 69.8 = 2239 cc 2.5 litre straight six 87.0 x 69.8 = 2490 cc 2.6 litre straight six 88.8 x 69.8 = 2594 cc [sorry Otto] 1.6 litre straight four 85.0 x 69.8 = 1584 cc

Originally Posted by 2 Fast 4 U I found an other engine: 3.6 litre straight six 95.0 x 85.0 = 3590 cc

. . . sure about that, Erick? Engine displacement listing convention of car manufacturers lists liter (litre) displacement breaks in 100cc increments from 00-99cc, i.e. 2200-2299cc is a 2.3L, not a 2.2L.

I know this is used for both displacement taxing purposes and displacement limits in racing classes . . .

[tekenaar]

Originally Posted by 2 Fast 4 U 2.2 litre straight six 82.5 x 69.8 = 2239 cc 2.5 litre straight six 87.0 x 69.8 = 2490 cc 2.6 litre straight six 88.8 x 69.8 = 2594 cc [sorry Otto] 1.6 litre straight four 85.0 x 69.8 = 1584 cc

. . . that made me curious about my 83mm bore listing for the '68 only, 1.5 4-cyl engine . . . oops, it's actually 82.5mm like your 2.3 (sorry) straight six above.