Isuzu turbo diesel tuning guide

[duckruls]

Everything is inter-related, without increasing the fuel you will struggle to get extra boost.

The max fuel screw increases the fuel across the whole rev range including when on full boost and the boost compensator is in operation.

It took me a couple of hours to setup, I disconnected and blocked the wastegate pipes and the boost compensator pipe, then I adjusted the max fuel screw until it would take full throttle from low revs without a puff of smoke when planting the throttle.

Next I connected everything back up and adjusted the boost controller until it was boosting at a steady 1 bar in all gears, then lots of accelerating in different gears and speeds checking for smoke, if it smokes turn down the max fuel screw if it does not smoke turn it up, I've set mine so that it barely smokes as I don't like it putting out a smoke screen when accelerating.

If you want to try some more in-depth stuff you can rotate the boost pressure compensator which will increase/decrease the fuel when on max boost only (but make sure you mark it first so you can get back to the standard position), you can also adjust the spring under the diaphram as this controls the amount of boost needed for the extra fuel to be added.

Here's a link to a very interesting article on mechanical diesel tuning, slightly different pump but the principles are the same, its worth reading all of the articles on the peugeot project car as they explain how to improve the performance of the diesel (exhaust/induction/fuel/boost):

http://autospeed.com/cms/A_109345/article.html

[the flash]

i don't see any smoke.

??

http://hotfootscat.ytmnd.com/

[KristofHA]

i mean i don't see "much" smoke when i accelerate.
Have a friend follow me and he also don't saw black smoke.

duckruls, thanks for the info. I'm going to read the article.
I also don't want a lot of smoke when accelerating, therefor this question.
fuel is expensive.
sorry if my bad english is confusing in my questions.

thanks again, i 'm going to read the article.

[Jack]

Anyone got any more information on this engine? 2mm bigger bore than the 1.7 and the same piston design (by the looks of the picture). Could this be a bored and stroked 1.7?

[Frisco]

The bedford midi engine

[Jack]

There's a 2.4 too.

[DutchNovaDiesel]

Anyone got any more information on this engine?

Could this be a bored and stroked 1.7?

45kW N/A

Nope, the 1.7 is a bored and stroked 1.5. Bigger bore isn't possible, have a look at this 1.7 cylinderhead:

And yes, it's FUBAR !

[Jack]

Fair enough!

[Gaz-M]

Wow, there isnt much of a firing ring there!

[Topbuzz]

Do these mods work with the isuzu engine as fitted in the Astra 1.7TD ECO4? (its a 1.7L DOHC 16v engine, Y17DT)?

[dooeytrials]

yes, thats the reason i didn't remove the filter/cat. I was afraid for the smoke test, even if i adjusted the fuel before the test.

Jack has about 108 hp if i'm not mistaken. This is done whit 1 bar.
If you calculate, 54 Hp without turbo, 1 bar turbo pressure gives 108 HP
If you use 1,5 bar, you woud have about 135 hp.1.7 bar = 145 hp.
Thats allot of power for a 1.7 diesel. Would it hold it....?

Are these figures for the 1.7 yer??? is it easy to get this much power......

im really quite interested in getting this much power...

[Jack]

Do these mods work with the isuzu engine as fitted in the Astra 1.7TD ECO4? (its a 1.7L DOHC 16v engine, Y17DT)?

I don't think so Alan, as the 16v engine is ECU controlled and has an electronic fuel pump...etc.

Having said that, I've never even worked on a 16v engine, much less tried these modifications! If it has an AFM, I can't see why it wouldn't respond to a slight increase in boost.

The best thing to do would be to try it!

[KristofHA]

Are these figures for the 1.7 yer??? is it easy to get this much power......

im really quite interested in getting this much power...

Hello,

Normally these “raw” calculations are right.

A few years ago a did a project in school on my Chevy van, a 5.7 V8. The project was to put on a turbo with lpg as fuel.
I did a lot op calculations to get the right turbo with the good turbo mapping.
These calculations here are based on the numbers I found from Jack.
You must put in mind I didn’t consider airtemp, outside temperature…

4 months ago I swapped my 1.7 isuzu for a 1.7 turbo. I did the swap because the diesel pump of the 1.7 was leaking and I read about the white ring and performance of the 1.7 T here on this forum.
I drive on veggie oil. Almost for a year now. Didn’t have any problems, except the leaking pump of the 1.7. I thought it was leaking because the engine had 240 000 km and it is 13 years old.
Now with the 1.7 T the pump is leaking again.
Is it easy to replace the seals?
Would the veggie oil be aggressive?
Another question.
I still have the original F13 transmission.
Now my clutch is slipping.
I have a new clutch of a 1.2 corsa A gasoline. I know this car also has a F13 transmission.
Should this clutch fit in the transmission of the diesel?
Kind regards,

Kristof

[RickGTE16V]

kristof , the pump is leaking cos of the veggie it attacks the seals, you need to get veggie seal kit , which seal is leaking , do not attempt to dismantle the pump yourself till your sure about what your doing , i did this and it took me 3 days to put it back together . depending which seal it is you can do it without stripping the pump .

[Jack]

I have a new clutch of a 1.2 corsa A gasoline. I know this car also has a F13 transmission.

You might want to consider a more suitable gearbox and clutch, the Isuzu puts out a tiny bit more torque than the 1.2!

[KristofHA]

kristof , the pump is leaking cos of the veggie it attacks the seals, you need to get veggie seal kit , which seal is leaking , do not attempt to dismantle the pump yourself till your sure about what your doing , i did this and it took me 3 days to put it back together . depending which seal it is you can do it without stripping the pump .

Thank you for the reply.
Can you put me in the right direction where to find "veggie seals"?

It is the seal at the rear of the pump, where the injectors are connected to.


Thanks for the reply Jack.
I now that the 1.2 don’t put much torque. But I thought because they both have a F13 transmission the clutch will fit.

I don't want to put a F16 or F18 transmission because then I need to change the axels to the wheels because they are bigger.

I heard the F15 transmission is the “strongest” I can use that fits without changing the axels?
Does the F15 has a “stronger” clutch?

Thanks!

[RickGTE16V]

ok kristof , thats the easiest seal to replace without dismantling the pump so your lucky , i got mine from a specialist diesel place , cost about 20 quid , say you want a seal kit for bio diesel / veggie oil , i cant remember the name of the company i bought mine from but if i do ill let you know , as for replacing it its like an o ring , you will need to disconnect the injector pipes and then youll see 4 star head bolts holding the end of the pump on , now under that end are springs and lots of small moving parts so be afraid , very afraid , anyway loosen the star bolts but DO NOT TAKE THEM ALL THE WAY OUT , until you can just ease the end of the pump out by about 8 mm , then you will be able to see the o ring , just cut it with a stanley knife then pull it out from its grove , then to fit the new one , cover it in grease and stretch it over the back of the pump and take one bolt out , slip the o ring past it and refit the bolt , one at a time so you do not withdraw the pump head any more than 8 mm or so away from the body , if you pull it too far the peices inside will fall outof place and your in for a nightmare , then after the ring is past all the bolts , seat it into the groove and gently tighten the pump head back down , make sure it seats sqaure , do each bolt a few turns at a time cos if you get the head back on off sqaure you will break the plunger too ( ive done this also) , just be careful , slow and make sure everythings clean and youll be alright , put your pipes back on and woohaa leak fixed - now your a diesel mechanic

[KristofHA]

Hello,

Thanks for the reply RickGTE16v!!!
Do you also drive on veggie oil. Is the rear seal the only one that is leaking quickly when driving on veggie oil?
If you remember the name of the comany, please let me now. I read that normaly veggie oil isn't agressive, only bio diesel is. But i don't want to take the risk of changing the seal a few month later.
Thanks again.


another thing,

I found that the final drive ratio of a F15 is 3,55.( it was from a 1.7TD soft turbo opel astra)
Does anyone now the final drive ratio of a F13 that is fitted in a Opel Combo 1.7 isuzu so i can compare. I hope the F15 has a lower final drive ratio than the F13. Now i driving 150 km/h at 4000 rpm.

Kind regards,

[RickGTE16V]

hey krystof , i do drive on veggie oil yeah , with the same engine as you and , unfortunatly veggie oil can be just as aggressive as bio diesel , its still a solvent and a very strong one , good luck with your gearbox

[KristofHA]

Thanks RickGTE16V,

How long do you drive on veggie oil?
I now almost 1 year.
Now only a few months with the 1.7TD.
Did you have any problems with the veggie?
I only have the leaking seal.
I filter the veggie oil to 1 micron.

[cavalierkc]

Everything is inter-related, without increasing the fuel you will struggle to get extra boost.

The max fuel screw increases the fuel across the whole rev range including when on full boost and the boost compensator is in operation.

It took me a couple of hours to setup, I disconnected and blocked the wastegate pipes and the boost compensator pipe, then I adjusted the max fuel screw until it would take full throttle from low revs without a puff of smoke when planting the throttle.

Next I connected everything back up and adjusted the boost controller until it was boosting at a steady 1 bar in all gears, then lots of accelerating in different gears and speeds checking for smoke, if it smokes turn down the max fuel screw if it does not smoke turn it up, I've set mine so that it barely smokes as I don't like it putting out a smoke screen when accelerating.

If you want to try some more in-depth stuff you can rotate the boost pressure compensator which will increase/decrease the fuel when on max boost only (but make sure you mark it first so you can get back to the standard position), you can also adjust the spring under the diaphram as this controls the amount of boost needed for the extra fuel to be added.

Here's a link to a very interesting article on mechanical diesel tuning, slightly different pump but the principles are the same, its worth reading all of the articles on the peugeot project car as they explain how to improve the performance of the diesel (exhaust/induction/fuel/boost):

http://autospeed.com/cms/A_109345/article.html

How do you disconnect and block the wastegate pipes and the boost compensator pipe? Can you post any pictures on how and where?

[duckruls]

The wastegate pipes are the two black pipes on the right of this picture, I have extended them so the boost controller is in an easy to access position but originally there is just a pipe connecting them, as a temporary way of blocking the pipes i just got two pieces of pipe the same diameter and put a bolt in one end of each bit of pipe, remove the original pipe and replace with the two blocked pipes.



The boost compensator pipe goes between the inlet manifold and the fuel compensator on the injection pump, if you look over the top of the engine behind the inlet manifold you should see the injection pump, on the very top of the injection pump you will see a small black pipe, if you follow the pipe it will go to the inlet manifold, same as the wastegate get 2 pieces of pipe and block the pipe at both ends with a bolt.

[Jack]

Surely the boost compsensator is there to tell the pump to use more fuel on boost? What are the advantages with blocking it off?

[duckruls]

I found it helpful to block the boost compensator off when setting up the fueling, when at low rpm going onto full throttle there is little or no initial boost (I am talking 1000 - 1200rpm), previously I have found it hard to stop the puff of smoke in this situation, although at full throttle the smoke level was ok when driving nomally I could always see a puff of smoke accelerating from low rpm.

By disconnecting the boost compensator I found it possible to fine tune the low rpm (full throttle) fueling, once the boost compensator is re-connected it takes care of the extra fuel that is needed when under boost while the tuning with it disconnected gets rid of the off boost smoke.

I'm sure people have different ways/opinions of the best way to do this but this worked for me, the car has just been through its first MOT with the tweaked 1.7TD fitted and the emissions were well within the limit and it still goes ok.

I am more interested in no smoke than the best possible performance, although saying that is does perform ok for an old diesel and has averaged 46mpg over the last 6000 miles

[Jack]

Ah I see! Makes sense now.