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Discussion Starter #1
Hi All,
Im about to take delivery of a 2.0 TS engine which had been built up for use with a turbo in a 105 GTV. The seller changed his mind about it and sold it to concentrate on his 101 Giulietta Spider project. I got it for a price which wasn't much more than what donor TS engines cost here in Germany so Im taking a risk with what he claims has been done to it. I wont get any receipts. Only the sellers word for it. Into the darkness I go....

Its never been started, but has apparently new timing chain, seals, bearings, pistons, liners and valves, All standard, allegedly., The head has been ported, which I can see in the photos and the valve seats ground/modified somewhat. The photos show a new timing chain, and the drilled crank with spiggot bush. All apparently carried out by a reputable Alfa garage..... in Greece. There is a decompression plate fitted to work with the turbo, and the standard cams have been reground to a turbo suitable profile.

So I want to fit this to my S2 Spider, without turbo. I will document progress here, although for now Im hoping for some advice on what I should do to ensure success. What can I check to make sure everything is as claimed? here is my plan:

  • Measure static compression to see if rings are working. Measure CR using oil and syringe method.
Head:
  • Remove/discard decompression plate, and based on above CR measurement get head shaved to achieve 10:7:1 or so. (anyone need a Decompression plate?)
  • dump cams and buy something appropriate. any recommendations? this is a road car for occasional track use. I know this is a big topic, and I will research carefully
  • check cam followers, valve stem seals and seats as per shop manual.
  • I am tempted to let the Head Shop check the valves, followers, stem seals etc when they shave the head surface, and then have them install the cams and set the valve clearances. I dont have a shim set. thoughts? am I being lazy?
Bottom End:
  • check bore-piston / ring clearances. It should be clear if pistons are new, and hopefully what type they are.
  • Should I remove the pistons and rods? I could then check the rings properly, but if the compression is ok, and the clearances also, is that enough?
  • check main bearing clearances. is the cap gap check enough or should I disassemble and use plastiguage etc?
  • check crank axial play.
  • crank run out? can this be done in situ?
  • spiggot bush diameter check
If there is anything else anyone can think of which I can check, your advice is much appreciated. I would rather not pull the whole thing down and start again, but I only want to do this once, and will do whatever is required.

Ive assemble heads, front ends, timed cams etc before, but never built a up a crank and pistons. With the shop manual and the usual books, I should be ok.

I know the above doesnt check balance in any way. Im not looking for super high rpm, but should I be checking or weighing things? or take a punt on that?

Otherwise, I plan to stick with my 40DCOEs and single plug 123 Distributor. There is a single plug TS engine on the Alfaholics website that seems to be ok, so Im going to try this approach for now as to use the parts from my existing Nord engine. One can always upgrade later. Plus it might make things simpler when I go to get my TUV approval :)

As said, all comment and suggestions are much appreciated!
 

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If you haven't got vernier wheels then its worth checking your deck highs and head thickness, otherwise your cam timing maybe effected. Do a chamber volume check to help calculate the CR. I would invest in a wide band/controller and a jetting kit. Your cams might be ok to use as is, I know saabs used theres in both turbo and N/A engines. You may limit the top rev performance, but torque is better. Build it, drive it, get it to its best(tune wise), play with your cam timing. DONT just buy and bolt things on. A carbed engine thats fueling properly and spark advancing properly to the cams demands will go way way better that anything factory built! And you won't need a rolling road, just some time and fuel lol. Anything over 10:1 CR is fine. Plug temps can play havoc with the power/running of an engine, so have 3 sets of different ratings. Lighten flyhweel, pulleys, crank scrapers would add 20hp!
 

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Discussion Starter #3
Thanks for the tip on deck heights etc. I used vernier timing gears on a previous (non-alfa) engine. are they commonly used/ available for Alfa Nord/TS? Ive not seen much mention of them.

The cam currently fitted is apparently ground to 9.5mm lift / 295 deg which doesnt seem very aggressive to me. We'll see. There is certainly something to be said for getting it on the road and developing from there.

A lightened flywheel is certainly on the list. I will need a new flywheel of some sort as the new engine doesnt come with one..
 

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More lift would be nice but the opening should be good for power to 7000RPM! Over 300degs seems to lose a bit of low end,but its how you time them thats really important. You will have to start thinking about runner lengths and stuff if you want the best out of 300+ cams. Make your own crank scrapers;)but don't have them touching lol
 

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Discussion Starter #5
I think Im going to switch the Rods with Nord items instead of shaving the head and when apart balance the pistons. Apparently this is a common trick. anyone else done it?

The engine has arrived and on first look seems mostly new inside. There are new Cam followers which is nice. Will post pics when head off.

Im still not convinced I can re-jet the carbs myself though. and if Im going to pay someone to do it, it would be be better to get it done once only, and that means having an optimised cam..... they are so dammed expensive though!
 

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Get a book on rejetting. That should have some tables and guides for the mains. Most carbs meter fuel to air well no matter how much air is pulled through them, its getting the delivered amount right to your engines needs. The main jets determine max fuel, the emulsion tubes bubble air into the fuel throughout the rev range and have jets to control the air. The carb manurfacturer will have sets and recommendations for jet sizing for your aplication and power targets. With a wide band lamba sensor you will easily be able to see wether to go up a size or down on full throttle runs and part throttle at different revs can show if you need to alter the air jets. You may even be able to change the enrichment pump jets, or adjust/bend the linkage to lean them off a tad, lean air jets can mask an over rich pump;) Getting it jetted close to right can give the engine its pull and staying power. When you get it right, you'll find you may have to alter things as the seasons alter. Just a tweek of the idle screws maybe all thats needed. Maybe a wide band on each pair of headers if you run a 4 into 2?
 

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Discussion Starter #7
an update on my little project here:

My local machine shop have advised that the scoring/marks in the bores were no good and that the liners needed boring or replacing. after looking at the options for new piston/liner sets, probable requirement for valve relief cuts and what I spent on the Nord Rods, Ive jumped in and gone for +0.5mm, 11.5 CR JE Pistons from Paul Spruell. Still waiting for them to pass German customs and then can get the old liners bored to suit. If anyone is considering forged pistons, the online options from the US are much, much cheaper than what I could find in the UK/Europe, even after paying the import duty.


The machine shop also reckons the small end bearings in the rods are out of round, so need to replace them. But what I hadn’t noticed was the deterioration of the crank bearing surface. See photo, plus there is also pitting which isn’t so clear in the photo. The regrind and nitride costs from the machine shop were astronomical, but I was recomended ps-schulze.de which sells complete remanufactured cranks with bearings for 500 euro. So the crank and bearings are in, and hopefully the pistons will show up next week.

Otherwise, everything is prepared for the old engine to come out tomorrow. Ive booked the car in to have the engine bay painted and a few rust spots repaired next week. However I don’t really want to pull out all wiring, plumbing, steering box etc. Has anyone managed to mask off this stuff and paint around it?

Ive also installed an electric fuel pump, but will put up a seperate post about that.
Happy 2015!
 

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Discussion Starter #8
Its been a long time since I updated this post....

From the above point, and following slow shipping and customs clearance, I received my shiny new pistons on Jan 17



I got them home and to my horror, they were the standard 84mm rather than the oversize 84.5 I had ordered to match my still-to-bored liners. Switching them out was fine, but shipping time and cost to the US is high, and it was a total nightmare trying to get my import tax refunded. In the end I gave up and ordered new 84mm liners locally to suit the pistons and Paul Spruell fixed me up for the difference.
The liners arrived and on test fitment /measurement tuned out to be 84.2mm and out of spec. They went back, another week was lost, and replaced with, finally, the right parts.



I balanced everything as best as possible for a home mechanic and fitted everything together. Too my horror I found the hairline mark in one of the pistons. It caught my fingernail and appeared to have propagated like a crack. JE Pistons and Spruell assured me that pistons don’t crack like this, but I was welcome to send it back to the US for examination. Ahhh!

I took it to my machine shop who polished the end of the mark out, confirming it was only superficial and nothing to worry about. At least this one was a false alarm....
 

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