Hugh_
|
| posted on 8/3/10 at 03:17 PM |
|
|
Dellorto 45s jetting for tuned 2.1 pinto
Could anyone offer some guidance of rough chokes/jet sizes/emulsions for twin Dellorto 45s on a modified pinto (spec below). I'll get it
RR'd once I've run it in as its a newly rebuilt engine so I'm just after settings to get me through the first 500-1000mls.
The spec is:
2.1 205 block
BV head (44.4mm inlet and 38.1mm outlet)
Kent GP2 cam
Dellort 45s
4-1 exhaust
Thanks
Hugh
|
|
|
|
|
ashg
|
| posted on 8/3/10 at 03:24 PM |
|
|
i thought the agreed consensus these days was that engines don't need running in.
every engine I have ever run in has always caused me trouble. now i just rebuild, then drive normally and haven't had any problems since.
each to their own i suppose.
Anything With Tits or Wheels Will cost you MONEY!!
Haynes Roadster (Finished)
Exocet (Finished & Sold)
New Project (Started)
|
|
|
snapper
|
| posted on 8/3/10 at 06:40 PM |
|
|
From Des Hammill's book these are the recomendations for the 45 Dellorto's for a modified 2000
38mm chokes
150 mains
7772.6 emulsion tubes
190 air correctors
40 or 45 accelerator pump jets
60 idle
7850.9 idle jet holder
8011.1 auxiliary venturis
float level shut off 15mm
float level droop 25mm
18 degs idle advance @ 1200 rpm
38 degs total mechanical advance by 3600 to 3800rpm.
if you have 36mm chokes fitted i would use them untill you get to the rolling road.
only the newest engines staight from the manufacturer don't need running in, a Pinto will need the rings bedding in to get a better gas seal.
The first 20 mins of the first start is held at 2500 rpm no less to bed in the cam and followers followed by some mixed driving to bed the rings
in.
I will be very interested in your results as i am just coming to the end of a 2.1 Pinto build myself, V6 pistons, Cosworth rods, 44.5 inlets, standard
exhaust in a very well flowed head and an RL31 cam with GSXR 750 Mikunies and Megajolt.
[Edited on 8/3/10 by snapper]
[Edited on 8/3/10 by snapper]
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
|
|
|
Hugh_
|
| posted on 8/3/10 at 08:16 PM |
|
|
Thanks snapper, I'll pull the carbs apart this evening and see what's in them at present and order anything I need and service kits
later.
I'm running a megajolt too, I've loaded the first 171bhp map from here as a
starting point and I'll see how that works as I havent found any dedicated 2.1 maps.
There's no way I'm not running in a rebuilt pinto bottom end, the head/cam has run before but on a different block; though I agree its
less necessary on a new factory built engine with todays manufacturing tolerances.
It's got mineral oil in it at present, and I'll change that after the first ~50miles for the same again; then go to semi at about
1000miles and fully-synthetic in due course.
|
|
|
Hugh_
|
| posted on 9/3/10 at 11:18 PM |
|
|
I pulled the carbs apart this evening to see what's in them.
Recommended / Have
Chokes 38mm / 36mm
Mains 150 / 160
Emulsion tubes 7772.6 / 7772.8
Air correctors 190 / 230
Accelerator pump jets 40 or 45 / 30
Idle 60 / 50
Idle jet holder 7850.9 / 7850.7
Auxiliary venturis 8011.1 / don't know (cant get them out  )
I've ordered the service kits, air correctors and emulsion tubes as these look the furthest out.
I'll let you know how I get on. Unfortunately doesnt look like its going to be this weekend as we're supporting the ladies at womens head
of the river race on Saturday, and racing the Hammersmith head on Sunday ourselves. Ho hum, too many hobbies...
|
|
|
cliftyhanger
|
| posted on 10/3/10 at 07:58 AM |
|
|
The idles may well need opening up too. May be worth getting one of those tiny drill sets so you can play. On my car (has emission dellortos) the rr
guy drilled the idles from 60 to 63, made all the difference. Remember the car runs on the idle circuit for light throttle openings when driving, not
just at idle.
|
|
|
Hugh_
|
| posted on 10/3/10 at 01:56 PM |
|
|
Cheers clifty, I'll see how I get on. Seeing as you arent a million miles from me, which RR did you use? Any feedback would be appreciated.
I was planning to taking it to Gerald Dale.
While we're on the subject of light/mid throttle, I have 5 progression holes, one of which is larger than the others. I know some 16v engines
need 5 rather than 3 holes, but will I be okay with 5 on a pinto?
|
|
|
cliftyhanger
|
| posted on 10/3/10 at 02:44 PM |
|
|
I too used gerald. Only one for a long way......
He doesn't keep much for dellorto's and resorts to drills!
I believe a gentleman can never have too many progression holes, only too few so you should be fine.
Might have to book him for an SU session in the near future, last time I tried he had just been flooded (water, not work)
|
|
|
