NA to TD Conversion?

[4BTA4ME]

I've been searching for my son on how to convert his 1986 NA 1.6 to TD. I have not had much luck in the search. We obviously need the LDA. Can he buy any 4bt core from Goldfarb for this? Any other suggestions. We will need to find a turbo too. Any suggestions there would help too. Thanks. Barry.
p.s He is looking for some additional performance increase also.

[spencebm]

in my opinion you wouldn't want the LDA on the naturally aspirated engine.  with a turbo you may get that engine too hot with the increase in fuel from the true turbo pump.  make sure to get a block with oil squirters and a head with the sodium filled valves to handle the turbo.

[jtanguay]

you could possibly just add a VNT turbo and increase the fueling slightly.

further playing with the governor to give more fueling in the upper rpm range will give even more peformance.

things that are recommended if you decide to turbo it are larger downpipe (2.5"), intercooler, and an EGT gauge to monitor the temps.  for an N/A you'd want to keep it below 1300F max where a true TD can reach max 1600F (for short periods of time... do not hold it at these temps!!!)

http://www.vwdiesel.net/phpBB/viewtopic.php?t=1306&highlight=project+potential+variable+vane

read that thread.  Jake was able to create a few pounds of boost right off blipping the throttle (no load!!) so that turbo can easily spool right off the line to give more oxygen to help burn the additional fuel.  this means you won't need the LDA.  the intercooler will further increase the oxygen density of the charge, and also decrease the EGT's to help keep the motor intact.

if doing this don't go crazy with fuel.  it will give you probably 10-20 hp boost at most.  keep an eye on smoke coming out the back, too much and you'll blow your engine.

you will also need to switch to a turbo oil.  high quality synthetic works great.

[4BTA4ME]

Jtanguay,
I was looking at Jake's project posting and I do see an LDA on his engine.
I'm confused about your statement of using the turbo's boost without an LDA. Is it adding fuel based on the governor or load compensation? Is that a less efficient use of fuel than using the LDA?

Larger downpipe and EGT monitor is in the plans.

Regarding temperature monitor, my brother makes digital engine system monitors. Teh one he made for my 4BTA project has high alarms that I set for every reading. So EGT's alarm at 1250 deg F and boost alarms at 26psi.
I don't know yet if he has the oilers on the 1.6. It seems to be a 1986 engine looking at the date/shift wheels on the block. We have the valve cover off and it has hydraulic lifters.

[malone]

Install the EGT probe in the exhaust manifold, before the turbo. EGT readings in the downpipe (after turbo) tend to be inaccurate.

1,300 F pre-turbo EGT is a good limit to establish for NA. 1,400 F briefly might be OK. Upgrade the oil cooler too.

[burn_your_money]

Jtanguay,
I was looking at Jake's project posting and I do see an LDA on his engine.
I'm confused about your statement of using the turbo's boost without an LDA. Is it adding fuel based on the governor or load compensation? Is that a less efficient use of fuel than using the LDA?

All the LDA does is increase the "on boost" fueling. You can make a NA pump put out just as much fuel as a pump with a LDA but it will smoke like mad when there is no boost. Basically what the LDA does is senses boost pressure and increases fuel accordingly.
Remember that the more complete burn, the lower the EGTs are. Unburnt fuel (black smoke) is hotter then properly burnt fuel.
If you run a TD pump use TD injectors, if you keep the NA pump use NA injectors

[4BTA4ME]

All the LDA does is increase the "on boost" fueling. You can make a NA pump put out just as much fuel as a pump with a LDA but it will smoke like mad when there is no boost. Basically what the LDA does is senses boost pressure and increases fuel accordingly.

  Isn't that the point of using the LDA? Effiecient use of fuel when it's needed for extra power?
I diverge:
I have plenty of experience with making smoke with a diesel. Both my 6BTA and 4BTA engines were more then happy to belch out wasted fuel if I turned them up too much.This, especially the case when you turn up the full load screw. On extreme load and  28psi boost conditions where I towed my boat up steep highway grades I saw the EGt's hitting 1,350 deg. F. My 4BTA truck FMIC has all air funneled through it and the radiator for maximum cooling of the boost temperatures. This is the best way to run the Cummins because they are hard to get up to optimum operating temperatures. Still under hot summer conditions more cooling is required by means of electric fans on the radiator.

If you run a TD pump use TD injectors, if you keep the NA pump use NA injectors

Thanks.  Hole type injectors  vs. pintle need to match the intended design of the pump pressures?

[jtanguay]

ah your right he does have a turbo pump on that motor... but i still believe you wouldn't need the LDA.  that turbo was pounding back the boost gauge @ 1500 rpm...  as long as you didn't floor it off the line, the smoke would be acceptable.

[dillenger1]

I definitely dont have the oil squirters,so that problem is solved.So if i dont use the LDA then im gonna be waisting fuel when im not in boost?Dont want that.Im looking to retain great fuel economy.I need a fine balance between performance and fuel conservation.What about dual in line turbos?Wouldnt that basically be the same as running the VNT,Good boost at low rpm,and also at high?
 thanks, ben

[burn_your_money]

You won't be wasting fuel if you don't turn it up. You'll actually be getting better mileage because you'll be increasing the A?F ratio in the engine