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Discussion Starter · #1 ·
I'm planning to build a new engine to be raced in a Manta on a 1/3 mile circle track next season. I've read some info here on various modifications but would appreciate some input based on the specific track engine rules : 2.4 L max., any non-roller cam, any valve, valve spring, etc., porting and polishing ok, decking block, shaving head ok, modified stock intake ok, headers ok.
550 cfm 2 barrel max.

Input also based on my resources : I have several good core 1.9 L core engines. I also have an excellent friend/race engine builder/machinist/sponsor to assist me. I own a custom auto fab shop and can do all but the machine work.

I'm looking for basic blueprints(for now) for the best engine(with a reasonable budget in mind) to compete engine-wise with the Fords, Toyotas, VW,s etc.

We raced last 2 seasons - the cars handle great, but at this track we need more than our slightly modified 1.9's.

Any and all input is greatly appreciated.
 

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boomerang opeler
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you need to talk to ralle bob if you want to do it pdq then private message or e-mail from his bios in the members profiles
 

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What's your budget? If roller rockers are allowed, then 8500+ rpms and 200+ hp are attainable by those rules....they're pretty liberal.

But figure on spending $6k or so on parts for an engine of that caliber. I built numerous circle track Opels over the years, so I know the 2.3 litre Fords can be beaten quite handily:)

Bob
 

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This guy (JCB) can drive!!! I had the pleasure to see him in action this summer, after all had to support any Opel effort. Can't wait till next season.

DAN
 

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Discussion Starter · #5 ·
Thanks for the replies!

I would like to keep my cash expense to around $3000.
Modifications in order of value for the dollar is probably needed. As competitive as we are already with the 1.9 I'm hoping this would build a reliable 2.4 or ? and put us where we want to be.

Roller rockers are OK also.

Our engines we have now are bored oversize to 2.0 L - one with forged flat top CP pistons, one with cast flat top 265 Chevy pistons. The heads are 1.9 with bigger valves and springs, shaved, little or no porting done, stock rockers; stock bottom end, basic headers, stock intake, ground in plenum area some; 32/36 webers; Pertronix ignition & coil.

I don't have all the detailed specs here, but maybe this gives you an idea.


Joe
 

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Best bet would be to get a Euro 2.2 engine, and bore to 97mm. This will get you a 2.3 litre displacement, and allow the use of the 2.2 'raised port' head. With minor tweaking, that head will outflow a full-tilt racing 1.9 head. If you spend the money on the 2.2 head, it will outflow a Chevy Bow-Tie head. But $3k isn't gonna get you there unfortunately.

Bob
 

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Discussion Starter · #7 ·
Can I build a 2.3 or 2.4 with some of my components and use a 2.2 head? Are there any new or used race prepped heads, cams, pistons, cranks, rods, etc. available?
What kind of power do you think a well built 2.4 with a full-tilt 1.9 head will produce.

Joe
 

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You can still make a lot of power, if you do a lot of R & D. I got my friend's Opel circle-track car to make 192 hp from a 2140 cc engine. I used a 2.2 crank in a .030" 1.9 block, and a 1.6 head with flat-top pistons (per our rules). Big valves, lots of porting, extremely ported intake, Holley 500 reworked to flow 640 cfm, custom header, roller rockers, stud girdle, healthy cam. So the only Euro parts we got were the 2.2 crank and the 1.6 head core (1.6 is the same core as a 1.9 except it has a small combustion chamber...hence more compression with flat-tops.) Everything else we did was either custom or modified 1.9 parts.

I don't have any leftover heads/blocks etc, the only thing I still have is the old racing header (1.75" primary tubes, to fit with a stock Opel intake on a Manta chassis....assuming you cut out the floor!), and maybe a few old cams. I can check on the cams. The last cam we ran that made the 'big hp' number I sold to 'davegt27' on this forum a few years back. The rest of the parts are history.

There is a way to make a 1.9 into a 2170 cc engine without going to an extreme bore size or welding the crankshaft. Any bigger will require a 2.2 or 2.4 crank, or welding the stock crank to get displacement.

Bob
 

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RallyBob said:

There is a way to make a 1.9 into a 2170 cc engine
This was what I was thinking as well. Either offset grind a 1.9 as you mentioned or use a 2.2 to get up to the max displacement. Using the Acura rods will remove the rod bolt availability issue... I received a flyer today from OGTS with some parts I ordered and they are getting $1200 for a 2.2 long block.

Cost wise there is probably little difference between a full prepped 1.9 head and a slightly modified 2.2 head with similar flow. With the 2.2 head you'd have the option to rework it later for considerably more flow when money allows....

-Travis
 

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Discussion Starter · #10 ·
I talked to a company 30 minutes from me that welds and offset grinds cranks and claims to have had excellent results. They estimated $300 to do one of these Opels.

One of these welded cranks is probably not as reliable as a used 2.2 or 2.4 crank? What is a good used OEM crank like this worth and are they around?

We can use domed pistons, so we should be able to get the compression we want. Are Acura rods the way to go?

Bob, the other mods you mentioned(heads, intake, etc.) about the 2140cc seems doable, with some assistance. And I am very interested in the header(we can cut the floor) and cams or at least the specs. Also the carb mods.

Thanks guys
Joe
 

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I still have the cams Bob sold me so your welcome to them if its not the one already in my race motor.

only problem i had the cam card was in my pocket when i washed my jeans so its history

you can ask OGTS and see if he has just a 2.2 crank some times he does

or you could buy my 2.2 crank along with the high dollar pistons $850

I also have a few 1.5 heads one I might let go if it went to someone that was going to use it for something more then just car shows.


good luck
davegt27
 

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Dave, that cam that I was referring to was a Cam Techniques grind, it was an F-333 intake profile with an F-324 exhaust profile. That equates to .518" intake lift/.504" exhaust lift, 266 intake/257 exhaust duration @ .050", 300/296 advertised duration, and 106 degree lobe separation. It pulled clean from 2500 rpms, started to wake up at 4500, changed exhaust 'note' at 5300 and really started pulling, and made peak power at 8800 rpms, but we ran it to 9200-9400. The funny part is I got to drive that car/cam combo at a road race course once, and when it was muffled and I was cruising through the pits, it was totally tractible and driveable. Almost streetable.

Dave, it sounds like you're ready to get out of Opels? I know you've got a lot of money and parts invested in engine components.

Joe, yes you can use a domed piston in your Opel engine, but try not to go too crazy. Tall domes hurt the flame propogation and can really hurt high-rpm power in these engines. A compromise of a small dome and milled head seems to work best. Of course, with a bigger displacement engine you won't need much of a dome anyway. My friend has a 2.5 litre street Opel, and it has custom 10.5:1 pistons (10.8 with head milling). Those pistons still have a dish in them!

The Acura rod is a nice way to get some more stroke from the engine. First of all, if you get an Eagle H-beam chromoly rod, it's something like $369 a set...cheap. They are 5.394" long, Opel rods are 5.039". Pins are lighter, and the big end is 1.771" for the Acura instead of 2.046" for the Opel. Offset-grind the crank and downsize the journal to the Acura size....bingo, you have the potential for .275" of stroke increase. In reality, this will probably be closer to .250" since there aren't too many virgin Opel cranks out there that will clean up that well, but it also depends on the skill of the guy grinding the crank. So, you can see this opens up a lot of doors. You could offset-grind a 2.2 crank, bore the 1.9 block to 94 mm, and have 2327 cc's, or go to 95 mm and have 2377 cc's...96 mm will get you 2427 cc's, etc. And you'd have cheap, light, strong rods that are longer than stock too, so your rod ratio doesn't completely go to hell.

I'll try to take a photo of the racing header. It's seen better days, it has some rust at the joints and a few dents and what-not, but it's nothing I'll ever use again.....they either closed or re-organized all the local circle tracks here in the Northeast that we used to run at, so the 'outlaw' mini-stocks are no longer run at all.
If you want it, I'll let it go cheap.....I spent 8 hours making it and another $110 in parts were invested, so you can get it for less than the cost of the parts. I think I still have the entire 3" exhaust and Loback racing muffler....those could be thrown in for free.

Bob
 

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Discussion Starter · #13 ·
I really appreciate everyone's input on this project! This education is invaluable towards my and my builder's R & D. I'm learning alot and will run this all by him. He's done alot of race engines, just not Opels. He will be grateful also. Again, thanks.

Dave, depending on which way we go with this, I may be interested in your Opel parts. If the cams specs can be verified one might be just what I need. Please tell me more about the 2.2 crank and pistons(which rods would be needed and the piston specs, etc.).....Thanks

Bob, I understand there is a benefit to using a 2.2 crank, but I already have 10 to 12 1.9 cranks. How close can I get with the Acura rods with an offset ground 1.9 crank? I also have as many 1.9 heads. Can't I get somewhere by building one of these to optimum? This seems like adequate potential for a reasonable expense.

I would like to buy the exhaust system you described. Let me know how to close this deal.

Joe
 

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Dave, it sounds like you're ready to get out of Opels? I know you've got a lot of money and parts invested in engine components.

yep this is true

have a high dollar Targa Top Kit floating around also, i hope i can get it back




davegt27

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Dave, it'll be sad to see you go. You've been into Opels a long time...

Joe, here's a pic I just took a few minutes ago of the racing header. I forgot it had header wrap on it (kinda ratty now), but you've gotta keep the heat away from the intake.
 

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Another view:
 

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Final view:
 

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Discussion Starter · #18 ·
Bob, the header looks good to me. I would like to get it. Thanks for the pictures.

When you can, please comment on my last post regarding using my 1.9 crank & head.

Thanks, Joe
 

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rods

What Acura application would have tose con rods guys? I want to do some more research on that option.

Never mind, I found it. B18a, right?
 

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Acura Rods - H beam

There's a new kid in town called "Eagle Rods".

They are forged in China from 4340? Well Chrome alloy steel and finish machined in USA. They have ARP rod bolts.

Just try "Eagle Rods" on EBay and stand back - there's lots of them.

Acura have 1.770" crank pins with 5.364? centre to centre length

Chrysler Neon may be worth a look 1.889" crank pins and about 0.100" longer centre to centre.

About $US300 a set of four

Also have bronze bushed pin ends.

Can't get ARP rod bolts for you Opel engine - just buy new rods, offset grind the crank; get suitable pistons: bore block etc. etc.
problem solved:rolleyes:
 
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