Hello to everyone,

I'm new to the forum and I hope I can get some assistance / guidance form some of you. I'm a mecanic enthusiast rather learn by doing. So fare, I have built my Lotus 7 replica (Westfield base), I rebuild a porsche 997 engine and rebuilt a mini copper JWC engine.
Unfortunately being in Belgium, it is impossible to make a "kit" road legal. Thus car is awaiting in my garage since about...15 years.
Nevertheless, this week I decided to play with it. However:

1) when starting the engine, it was extremely noisy (lots of backfire, misfire, etc). I re calibrated the TPS sensor and the airflow. All 4 barrels are at same airflow (4kg/h), idlle at 900rpm and TPS set at idlle to 0,750volts.
Engine runs more smoothly and fully sustain iddle speed.

2) Yet, when depressing accelerator to increase rpm, engine rattle to much between 2500rpm and 3500rpm then get more stable. Tat that rpm the engine is also having some misfire noise ( I guess this may be somehow normal)

Thus I wonder if and how I can better tune the engine to get a smooth rpm ramp up while also keeping a good iddle speed.

Many thanks for your advise and support.

Thibaut

Westfields Sportscar Sew
Duratec 2.0 engine (less than 500 miles)
New Webcon Alpha performance kit ( throttle bodies + eau) K24002

[Edited on 30/8/24 by thibaut001]

Hi all,...Non one has any experience in this?

Have you got a syncrometer?
linky

You need to get the throttle bodies balanced spot on before tackling any of the other tuning.

Also if you have access to fuel pressure testing equipment, that would be worth checking both with engine off and on - if the fuel pressure regulator has a vacuum connection, the pressure will vary according to manifold pressure. The spec sheet for the kit you have should give required pressures, but likely to be in the 3-5 bar (300-500kpa) range.
If you have access to any live data from the ecu, check that obvious things correlate, ie engine off manifold pressure should be 100kpa, idiling manifold pressure in the 30-60kpa range(may be higher until the tuning is optimised), ambient air temp is correct, coolant temp is correct.

What software (if any) are you using with the webcon ecu, and what base map have you been supplied?
It is unlikely that the base map will be ready to use, and will require further mapping to be ready for the road.

Certainly in the UK, only Weber Alpha dealers have access to their software for carrying out mapping, I don't think any other software is workable for this purpose at present.

Dave

I don't think Webber do the Alpha injection kit anymore, however, I believe ERA (formally Tiger) do still market the setup, If you give them a call they will help I'm sure.

Hi Thanks for the advises.

Yet to m knowledge, the ECU has been mapped and tuned to Westfields / Duratec 2.0l engine and should not be changed? Would be clearly interesting to get access to the mapping yet not sure what's software to use nor how to use it.

==> Nevertheless after a first tuning what I found strange is that:
1) Engine start nicely even at cold.
2) Engine keeps idle speed at +-900rpm and keeps it nicely.
3) When increasing engine speed, I Sart having misfire and rattle noise when ramping up in RPM.
4) when back to low RPM/ idle speed it engine works nicely.

I'm also certain this is a poor tuning and as indicated by obfripper, could this be caused by the wrong tuning sequence? I did the following 1) unscrew completely idle speed; 2) adjust TPS sensor; 3) adjust Iddle Speed, 4)Balanced 4 barrels with syncrhometer at 4kg/h.

As mentioned by obfripper, I may re do it staring with 1) unscrew idle speed to fully close all barrels,2) barrels air adjustment at 4kg/h each; 3) tune TPS sensor, 4) Idle Speed.

PS : Unfortunately WebCon Alpha is out of support and Webcon can not assist. Looks like Tiger racing (ERA) has still the expertise.

Thibaut

TO all,

Yes I confirm after having rest all to ZERO (idle 100% closed, unbalanced the 2 bossies; closed the fair airflow and TPS reset). Then:
A) balance the 2 carbs to ensue the open and closed in sync. Just screw the link till it just touch the first carb (left)
B) start engin and play with gas till temperature is +- ok
C) individual airflow with synchro meter to measure between 4 and 5. Once the first is set up replicate the set reading to all boddies (playing with airflow screw and very light idlle)
C) tune idle speed lightly on left throttle body
D) fine tune idlle on right buddy . Be careful not bias the airflow. The name of the game is ti tune with synchro meter,


Fairly easy yet requires some patience and very light adjustments.

Works great, keep nice idlle speed of 900rpm and ramp up great

Thanks

Thibaut