Boost returned, but, engine power presentation has changed?

[herbiemercman]

Hi Style, I was brought up in Milangavie just north of Glasgow, left there when i was 12 years old. I used to play down by the burn near the waterworks and Tannoche Loche.

The geordies like there newky brown and the Scots like a pint of heavy and a dram, followed by a fish supper. Herbie.

[herbiemercman]

Just purchased a wideband "AEM" AFR Gauge with the Bosch sender, circa £200, Noz made me realize the importance of this monitoring piece of equipment, to me as a parrallel, it is a bit like having some thing which keeps an eye on your timing belt, because if your AFR goes a drift,and you "lean out", you could have a goosed engine, and turbo charged cars at the levels my NAT is working at need this essential piece of electronic equipment.

The basic stage #1 tune for the NAT is very good for the price, IMHO, but when you get involved and start to use the car, and observe the performance, then you start developing your own requirements, here is my list coming from usage experience:

 

1. Changed stage 4 clutch to a stage 2 street clutch,the stage 4 is un-driveable, either in or out, and no in-between.

2. Oil cooler fitted as oil temp hitting 135 deg. C., now 90 deg.C, thermostat controlled.

3. Three home made ali / ceramic heat shields fitted over the downpipe, as the bonnet ,brake servo, and bulk head getting too hot.

4. Two batteries failed, so had to build a insulated box around the third one, due to ambient temps under the bonnet much higher than stock temps cooking them, also two air vents fitted directly above the battery and the conical air intake filter.

5. Fitted a higher temp starter relay which has a built in temp cut out on the stock cars, took ages to locate the non starting problem.

6. Replaced the failed stock cylinder head gasket for a multi-layer 2T gasket after 3,000 miles. big job, not for the faint hearted and big bucks, CR reduced to 9to1 from stock 10to1.

7. Boost pipe bursted over the turbo, no boost, very hard to find the problem without removing all the pipes, also fitted more robust clips.

8.Wastegate valve/dump valve, started sticking due to lack of use and carbon build up, full strip down and cleaning, then silicon special lube applied to the mushroom shaft, caused mega problems to find and solve.

9. The stock ECU was fitted with a Geedy Emanage piggy back and mapped with this situation, great performance, BUT three years on and very few, if any Tuners/Mappers, refuse to get involved with this system, apparently you need a laptop with XL software to check or change the MAP, so glad i no longer need this.! A company in the south of England wanted £3K to replace my set up ECU and re-map. lol. !

END OF LIST.. (I FU--ING) HOPE SO. !

 

SO IF YOU GET A BARGAIN NAT CONVERSION, THEN JUST DOUBLE THE DOSH YOU SHELLED OUT OVER THE FIRST 3 YEARS.

You will learn a lot and will suffer a lot, i have no regrets, and learned also how important this Club is! Herbie.

Edited February 14, 2020 by herbiemercman
added extra text. (see edit history)

[herbiemercman]

Hi Adam, Sorry i forgot to say thanks for your post on the thread logic, i can see your point, but all the problems were circulating the engine tuning and mapping etc, but if you apply the FMEA system, (failure mode effect analysis) and then run the "cause and effect" approach, then this helps give more focus to the different problems.

Your point re the need for dyno quantatative data is correct, the problem i had was getting hold of this, see my last posting with ref to the Greedy Emanage piggy backs. Herbie.

[herbiemercman]

Hi Scooter, thank you for your posting, the "layman's way" you made your points was very good, if you read my last sort of epilog of this whole journey, you will see that i have managed to get back to the original NAT performance, good respose at the bottom end, early and lively spooling and shooting up to 90mph in third gear, smooth tick over and instant cold starts. I also like knowing i now have a class wideband AFR and a thicker more robust cylinder head gasket.

I am a "happy bunny", hope it all lasts? Herbie.

[Style]

Sounds like you're roughly back to where you were before, nicely done

 

If you come into some money in the future, an ECU upgrade would be first on the cards if you ask me!

[Scooter]

 

If you come into some money in the future, an ECU upgrade would be first on the cards if you ask me!

 

.....but then just be careful re the gearbox , you could spend the cash and get a much better running/tuned engine that might then just tip the W58 over the edge! As with all modding there can be a knock on effect of each 'tweak'

 

I'd be monitoring the AFR etc and rebuilding trust at this point, then decide how to move on depending on how much the recent experience has jaded you or reignited you.

[herbiemercman]

Hi Scooter, I have a saying, its one i took from the top of my head and it is: "some good thinks come out of adversity", yes the journey for 3 months has been up and down, no way did i tackle the cylinder head gasket without trepidation, my local Merc. expert just said it was complex and time consuming, with several critical areas.

However it is like most things in life, if you want the feeling of assonance, and not the feeling of cognitive dissenants, then you have to push on through, and then wallow in the result if it is good, and my result is good, went for a blast today, fantastic machine, seemed a long time since i pulled into my drive way with a boiling engine and diagnosed the head gasket.

I have five members who have been a god send to me, and they know who they are, as you do. Herbie.