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Just been to John Clarkson of Chorley , Lancs for power runs in my Eunos 1.6 Turbo
http://www.johnclarksonautos.com

Met with Andrew - great bloke and does a good job.

Did 5 power runs, looked in between runs for issues to correct, made adjustments to MBC and wastegate actuator.

Upshot was 266 bhp and 226 lbft torque at 16 psi, thought this was a bit too much boost as I dont know whether internals are stock or modded so reduced to 13 psi.
Spent 2.5 hours on rolling road, full printouts boost AFR, duty cycle, power , torque - cost 90 quid.

Printout showed accurately where I am over rich above 4,500 r.p.m AFR approx 10.5.. have now adjusted i'j map duty cycles.

Also boost was showing drop of 2 psi at 3500 rpm then buld up to it's peak at 5500 rpm. need to investigate whether this is due to Manual Boost controller if so looks like upgrade to electronic boost controller. Andrew said first reduce iridium plug gaps down to 0.6 mm currently 0.8 mm to eliminate possibility of spark being quenched due to boost conditions( evo owners run 0.6mm)

Also duty cycle charts showed spikes on a generally linear plot around 4500 rpm and up instead of steady linear plot. Andrew said ecu not liking injectors somehow (550 cc),

anyone else had this issue ?????

Still car drives great and goes like a train

Highly recommended....great bloke , top equipment
You wont be disappointed

Tim
 

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Perhaps you should mention your exact location etc. Theres a few peeps in preston/blackpool and liverpool/southport that would be interested in this service i think.

Also mention whether there was any adjustment made by you and do you have any previous dyno plots?
 

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Discussion Starter · #3 ·
Perhaps you should mention your exact location etc. Theres a few peeps in preston/blackpool and liverpool/southport that would be interested in this service i think.

Also mention whether there was any adjustment made by you and do you have any previous dyno plots?
I live in Hindley, Wigan about 10 miles away from Chorley

We discusssd results and Andrew adjusted MBC and wastegate actuator rod between runs.

I did not have my laptop with me( broken) otherwise I would have adjusted fuel injector maps between runs as mentioned before above 4500 rpm.
No , this is my first dyno run however Andrew did have another MX5 turbo run saved on system to compare against. Roughly same [email protected] rpm but mine produced more torque across rev range
 

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Dan
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nice work -I'm only in St.Annes so not too far from chorley

might check them out when I need mine rolling road tuned.
Cheers
dan
 

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Discussion Starter · #5 ·
nice work -I'm only in St.Annes so not too far from chorley

might check them out when I need mine rolling road tuned.
Cheers
dan
UPDATE

The boost peaked at 14 [email protected] rpm then dropped to 11 psi as wastegate opened then climbed back to 14 [email protected] rpm.

I experimented by partially blocking ( using a section of rawlplug) wastegate actuator boost pipe connection ( slows response time of actuator) and have now reduced this drop to less than 1 psi... no need for electronic boost control... RESULT

next job is to remove MAF completely, running off MAP sensor now so redundant apart from IAT sensor inside.
Will buy GM Open IAT sensor . Only downside I think will be more audible turbo stall/flutter on backing off throttle

keep on tinkering.........

Tim
 

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Some good figures there

What turbo is it you have exactly? have you considered perhaps using a helper spring to keep the wastegate in check since you are running fairly high boost levels?
 

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Discussion Starter · #7 ·
Some good figures there

What turbo is it you have exactly? have you considered perhaps using a helper spring to keep the wastegate in check since you are running fairly high boost levels?
no need for helper spring.. problem is not boost limit but control once at the limit

I have tried to identify my turbo but it doesn't match with anything I see on line.

it is a Garrett turbo with a compressor A/R of 0.48, physically looks like the GT 2860 series
 
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