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Discussion Starter #1
If anybody is interested I am just building a new TS engine for my 105 coupe. The engine should be completed in the next couple of weeks, running 11:1 comp with Kent Cams, Omex ignition and twin 45's. Should be good for 170+HP I hope. I will move to Jenvey's after I have got it running properly on carbs. I must mention AH Developments in Hartley Witney who know everything and my local machine shop for drilling pilot holes and spending hours drilling out crank oilway taps to clean it all up..they are in Burgess Hill if anybody is interested and VERY reasonably priced. Alfaholics will be supplying their new lightweight flywheel and manifold/system with lambda boss (for fuelling setup only).

I know need to know where to get a FULLY rebuilt box on exchange.

Cheers
Steve
 

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Updates

Steve;

Who is Kent cams?
Are you staying with stock compression at 10:1?
What pilot holes are you talking about?
How are you triggering your ignition?

Thanks,
Wes
 

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Discussion Starter #3
11:1 compression. Kent cams are one of the big UK camshaft companies, Adie at AHM in Hartley Witney has designed a cam profile (both inlet and exhaust) that they grind for him.

The pilot hole is in the end of the crank to take the gearbox input shaft brass bearing. The TS engine is a lottery as to whether it will have the hole in place from the factory, unfortunately mine didnt !!

Ignition triggering uses standard TS front pulley with standard 60 tooth (58 + 2 missing) trigger wheel. This pulley also has both the front two v-groove's removed as only one is needed form the original three.

NB. When I said AH developments, I meant AH Motorsport (AHM)

Steve
 

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Thanks

Oh, those pilots. My twinsparks came with those pilot holes. Jim at Autocomponenti said he could provide me with a good cam profile. I'm worried about the 11:1 compression ratio (I see you wrote) with 92 unleaded. Paul Spruell has forged pistons, liners, and rings with are over $1000 at 10.5:1. Omex I'll have to look up. Put it in this weekend so we can hear how it runs on 92 octane.
Thanks,
Wes
 

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As for the pilot hole... MAKE SURE it is the same depth as the 115 series 2L - roughly 1/4" deeper than the pilot bushing. A friend had an alfetta crank drilled to use with a transmission and the hole was just deep enough for the bushing; you could not bolt up the trans - the input shaft needs the extra space in front of the bushing.
 

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Discussion Starter #7
1/4" you say, I am not sure I allowed that much, only time will tell I suppose. I dont suppose an angle grinder on the input shaft is in the workshop manual
 

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Cam and Compression details

I'm very interested in this project.
How do you propose to get the CR up to 11:1, there is very little to take off the head before you get to the valve seats, how much will be removed from the head.
I would also be interested in the cams, are they the same as the C&B cams, if not or not sure do you have the figures for the cams, lift, duration, etc. Which Omex system have you purchased.
What pistons are you running?

That's enough questions for now!!!!
 

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11:1 CR from high dome pistons. I had some 11.5's and got 12.3 CR (for race fuel only!) by shaving the head 0.040 inches - 0.070 is about all that it'll take, and then you're into the hemi taper and have some head gasket problems.

Robert
 

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11:1 compression

Steve;

Let us know about pinging with the high compression ratio. How soon will your engine be up and running?


Wes
 

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60s Racer,
were did you buy the pistons?
Regarding the CR does this mean that taking 0.040 inches - 0.070 is good for raising the CR by approx .8, therefore approx 10.7 - 10.8, looks like I will need the pistons.

What cam's did you use and what ignition and how did you fuel the car?
 

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Discussion Starter #12
I have to say that the majority of the info I have gained to decide how to build this engine has been from others, my expertise is Audi Quattro Turbo's so bear with me !

On the advice of Adie from AHM the standard pistons were used and valve pockets modified to take 11.4mm lift cams. Using standard pistons means taking the head to its limit which is right down to just avoiding the seat insert (to avoid grinding as opposed to skimming). This should theoretically give 11:1 max and without pipette and lots of extra time to measure it all I will take his word for it as he has built many to 11:1 spec and through measuring has found that this ratio ends up having to skim the head as above.

Alternatives to the above are to buy forged (Mahle I assume) domed pistons that require no head skimming (apart from normal clean up obviously), my conclusion was that skimming a head costs £40 roughly (at my local machine shop anyway) and forged pistons cost around £700-800. As a result I would not be too concerned if it only ended up at 10.8:1 or so.

Ignition is from Omex and triggered from the standard front pulley wheel (60-2) and sensor. AHM provide blanking plate/plug for the two distributors. All quite straightforward. The only issue is where to put the coil packs as there is little room in the engine bay. I have decided to put it all behind the dash and have the HT leads passing through the bulkhead. This is how Max's at Alfaholics has been done and looks good. I have got the Omex OMEM500 as I want to use throttle bodies later but need to get it all running simply first .

The cams are a profile that AHM get ground by Kent, I have had Kent do stuff with Quattro Turbo's before and they are very helpful and more than happy to sort out the best profile. I have no idea of the timing of these cams but will ask AHM. NB. Getting a one off profile entered into Kents machining process is expensive so I would only ever suggest that an 'end-user' buys from somewhere like AHM or wherever as the economy of scale is only relevant if you can sell multiple pairs.

I do admit that I have not applied extensive technical input into this engine, this is simply due to time as I have three quattro's in states of partial rebuild (debuild would be a better description). I hope it works out and will let everybody know what happens in due course. All I need now is the cams, 2 weeks apparently, flywheel/exhaust from Alfaholics and a pair of 45DCOE's. I was going to use 40's but figured that 45's on 36chokes would be more suitable.

Also I need a gearbox as mine is whining/whingeing/arguing quite badly......

Should all be together within the month but I reserve the right to talk complete nonsense.

Steve
 

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Steve,
please keep us posted. I have done things in a different order. I have a OMEX 600 system with Trottle bodies. I decided that I would get this working on the standard engine first and then do the head work. Any more details around cams and modifications to the head, porting, valve size changes, etc would be really useful. As of yet I am still running the STD "distributors" want DIS system did you use.
 

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Discussion Starter #14
The DIS uses standard wasted spark coil pack and ignition amp but doubles up so the 'wasted' spark actually fires the twin spark of the particular cylinder. You still have a wasted cylinder as the Omex only has two ingition fire signals but you have two ignition amps and two coil packs. So for each of the two ingnition output signals from the ECU you get four sparks (2 used, 2 wasted)

I assume as you have throttle bodies and Omex that you are not using the variable inlet timing with the standard cams? Although I assume you could use the Omex auxilliary shift light output to drive this at a certain rev limit?

I have done zero mods to the head apart from skimming, I intend to build a new head later.

Also I need to machine a plate to cover the variable timing actuator.

Steve
 

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Steve,
thanks for the reply, from which car did you use the DIS, I already have the Omex system up and running with the std head and disty's, I was just wondering if there was a reasonally priced solution to move to DIS. I can then tidy the engine bay up by removing the the disty driven by the Cam' that is always in the way when you go to do engine work on the car.
 

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Discussion Starter #16
I believe your Omex may have to be modified by the factory as mine had to be sent back to remove the internal ignition amp by AHM. I assume that this is because the single (internal) ignition amp is not man enough to drive two coil packs. I dont think this is a difficult thing to do yourself, its just that I bought my Omex from AHM secondhand so thought they may as well do it, you may lose any warranty though if you do it yourself.

I can only advise you speak to AHM as he sourced the Intermotor ignition amps and (unknown) coil packs. You will need the blanking plug and plate from them also for when you take the disti's off.

The parts to get your ignition fully sorted are reasonably priced, do you still use the Motronic to run the ignition though? Or have you interfaced the Omex with the standard ignition drivers and coils/disti's? Also, Iassume if you still have the Motronic running then it is operating the cam timing actuator?

Do you run a MAP sensor or TPS for the Omex?

Steve
 

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steveurq said:
Alternatives to the above are to buy forged (Mahle I assume) domed pistons that require no head skimming (apart from normal clean up obviously), my conclusion was that skimming a head costs £40 roughly (at my local machine shop anyway) and forged pistons cost around £700-800. As a result I would not be too concerned if it only ended up at 10.8:1 or so.
Steve

I don't know a lot about the TS; but we tried raising the compression in the 1600 to 2L engines by milling the head in our racing engines - and we had problems with head gasket sealing. Getting to 11:1 cuts pretty deep into the hemi chamber shape - the outer diameter gets smaller. So the gasket seals outside the combustion chamber and the little ledge that remains becomes a quench problem. So be careful - I ended up with a lot more problems than saving a few $$ was worth. And we ended up with forged pistons anyway - they are lighter and use better rings, so the engine ended up better and without problems.

Robert
 

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I am using the std amps, colis and "distributors" and the std ignition drivers from the Omex system. The Omex 600 as a VTEC feature build in with its own output, but I will not need this anyway with the race cams.


60sRacer, thanks for the advice, do you have any idea were I would be able to buy high compression pistons for the Twin Spark, this are very expensive in the UK.
 

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As I said, I'm not up on the TS - perhaps some folks here will chime in. But look at the technical issues for the 2L - 85 mm bore is the same, cranks are interchangable as are con rods, so deck height should be the same (should? could?). If so, then any 2L piston would work OK. The sleeves may be different.

Robert
 

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The camber in the head is different, the pistons on a Nord 2 Litre are domed whereas the twinspark as a flat pistons. Do you know the name of the company that makes the high compresiion piston for the Nord 2 litre.
 
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