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  Topic Review (Newest First)
05-30-2018 08:23 AM
kpc655 I'm currently working to port another head and set it up for 48's. Should add some RPM and HP....it'll be back on the dyno towards the end of summer.
05-04-2018 02:22 AM
Veep
Quote:
Originally Posted by kpc655 View Post
My race ts head made peak power around 24 deg total advance. 28 sounds quite high
I have to check what the advance is set at now. but for sure way less than 28 degr. The first dyno guy (a inexperienced one it appeared with TS engines...new guy in the shop, old one took the plunge to be self employed) had it at that and that allmost ruined my new engine..(besides some other ploblems that had to be taken care off)
05-03-2018 09:59 AM
kpc655 My race ts head made peak power around 24 deg total advance. 28 sounds quite high
05-02-2018 11:55 AM
hunttheshunt
Quote:
Originally Posted by ianellisalfa
For me a twinspark on original EFI just doesn't sound like an Alfa!
Exactly, Ian. Sounds like an Opel.
05-02-2018 06:21 AM
iachella Thanks for the offer, Stephen. You can send me a private message or email if you find the harness. Email address bellow my signature.

Ian - I too have an Emerald installed in my twin spark. I'd like to communicate offline with you too, if that's OK. I'm still tuning so I have some questions for the more experienced.

Thanks,
05-01-2018 03:08 PM
ianellisalfa I have a twinspark in my road legal track car running on TBs & stand alone ECU (Emerald) whilst in my daily driver I have a twinspark on Webers with the original Alfa (Bosch) ECU running the ignition (twin distributors) and a throttle pot (the variator is hard-wired by a switch on the dash). The latter was much cheaper to build & install, albeit about 35bhp less powerful but is ideal for road use - the most unreliable aspect being the 3 Bosch relays that control the ignition & fuel pump!
I also have a Giulia Ti with a tuned 1750 (oversized to 1.9) pushing out about 150bhp (i.e. stock 2.0 twinspark bhp) which looks great, but cost more to rebuild, and isn't as easy to drive in traffic due to the light flywheel & slight stumble at low rpm...
For me a twinspark on original EFI just doesn't sound like an Alfa!
05-01-2018 02:21 AM
hunttheshunt
Quote:
Originally Posted by sdamant View Post
hi, I am pretty sure I am right about the advance that's 28 degrees TOTAL , so say 8 degrees static and then 20 degrees mechanical

Stephen
On a TS you´re pretty sure way wrong; especially when modified and running with 2 plugs.
04-30-2018 01:33 PM
nealric
Quote:
Originally Posted by Richard/SIA View Post
...a computer chip/EFI is just sand with pretensions of grandeur!

When EFI fails you call a tow truck, when Webers have an issue you can still get home on your own or make the adjustment on the spot.
Lot more threads here for help with EFI issues than for Webers.
The thing is, properly setup EFI doesn't really have issues. The help threads you see on the BB are mostly for stone age Bosch L-Jet stuff. A modern aftermarket EFI eliminates all of the disadvantages other than complexity of initial setup.
04-30-2018 11:05 AM
sdamant Hi, I will be back in my workshop mid May and will have a look to see what I have in the way of wiring harnesses....over the years I have collected two T/S engines one was bare but the other came with a large box of "bits"...if I have a harness I will let you know and you are welcome to it.

Stephen
04-30-2018 11:01 AM
sdamant Ok my reasons for going the T/S route , my NORD engine is very tired , needs a rebuild...I have a pristine T/S engine , and then ultimately with development I will be able to get more usable power from the T/S. I am keen to keep the under- bonnet looking as original as possible hence the plan to use carbs and an 8 wire distributor . The cams issue has become "interesting" in that apparently I am right about the standard 75 T/S exhaust cam timing and as I have another T/S engine I will use the spare exhaust cam on the inlet which as far as I can see will give the same timing/ profile as the C&B cams listed as performance street .
04-30-2018 10:54 AM
sdamant hi, I am pretty sure I am right about the advance that's 28 degrees TOTAL , so say 8 degrees static and then 20 degrees mechanical

Stephen
04-29-2018 01:50 PM
Bertiebloke
Quote:
Originally Posted by Veep View Post
a TS conversion will cost more than a good rebuild on a nord, with some tuning. Will simple work and good cam selection you get the same power for less money than the conversion. Besides that: TS wants a more classic look, that needs a 155 head without all the fitting points for distributors and VVT.
Contact RJR on cams with torque delivery. Also for the 75/155 btw... but for a classic look, and more than sufficient power: dont do a TS conversion..
The twinspark vs Nord decision was one I had to make last year and I was pretty open to both options. The Nord option was always going to be substantially lower cost and thanks to a helpful AROC member I managed to source a well built lightly tuned and balanced engine with a bit of head work but standard valves and 12mm C&B cams and 123 distributor. With standard 40mm carbs and exhaust/ manifold it puts out 160hp at 5300rpm with a pretty flat torque curve from 2300-5300 rpm. I think that's probably not too far from a mildly tuned twinspark at lower cost.

Factors that affected my decision were
  • I wanted to keep the sound and feel of carbs
  • Originality was a factor
  • There was some faffing around to get speedo to work with twinspark plus more modifications
  • Nord works best with injection which I felt mitigated against my first 2 points
  • It was actually quite difficult to find a twinspark and a good Nord came available
  • The Nord option was several thousand lower cost
I think if I'd wanted 180hp + car then I'd have gone Twinspark but I'm very happy with what I've got which pulls cleanly from tickover to redline. It's enough for a semi daily driver.
04-29-2018 09:36 AM
Veep a TS conversion will cost more than a good rebuild on a nord, with some tuning. Will simple work and good cam selection you get the same power for less money than the conversion. Besides that: TS wants a more classic look, that needs a 155 head without all the fitting points for distributors and VVT.
Contact RJR on cams with torque delivery. Also for the 75/155 btw... but for a classic look, and more than sufficient power: dont do a TS conversion..
04-29-2018 04:39 AM
Craig_m67 What's the benefit of a TS on carbs without variable cam versus a hot Nord?

Is there any?
This isn't a sarcastic post btw.. I'm interested in what gains are expected
04-29-2018 02:42 AM
hunttheshunt
Quote:
Originally Posted by iachella View Post
Stephen:

On the first question, you are correct. 28 deg max advance is the commonly measured value.
What ? On a TS ? That´s nearly 10 degrees too much.

A properly improved Nord needs 28-30 degrees; TS needs way less.
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