Joining the 4BD1 turbo fitting group - some help please!

[Muddy Boots]

After many years following some fabulous posts I too want to join the 'try it myself turbo' on my 1988 4BD1 (cost is a large part of it verses drive-in drive-out!) and like others I can wield a spanner but I'm not a garage wizz! Going for a HE221w and standard manifold... however first stumbling block was genuine exhaust manifold 8943662470 is no longer available through Isuzu dealers at $280 - $320, back to full at $600 - $650 + gst unless anyone knows different? If I go down the China route has anyone got a recommendation from personal experience as I know quality, durability and fit varies hugely [bigsad] Opposite to that has anyone had a flash cross-over manifold made up that takes the Holset 5.5cm, supplier, cost? And any thoughts on a few spare part numbers I haven't been able to find; engine gasket set I had was 5878104620 and appears only as Eazyparts 2A6006, is this correct or are there others? Also is there a part number for the oil feed pipe from block to alternator, is the rubber hose by the bypass hose on the pump just standard hose contorted to fit up to the heater pipe or is there a part number? and does anyone know a supplier for the alternator pulley? mine came with a twin pulley wheel (probably for an early Patrol or similar) Lots of questions I know, but hoping someone has a few spare moments to fill some of the knowledge gaps[bigsmile1]

Cheers Ted

Series 2A ute
GS daily drive
GS in the shed for above surgery!

[Phil B]

Most of the cost of the “kit” turbos account for the research involved in making everything fit and function
Be prepared to research on FB and here to fond out what others have done
It appears that many have succeeded with this but many have failed
Research is essential if you don’t want to spend the money for the kits

[Muddy Boots]

Thanks for the well meaning words Phil, and researched I have but like many before me and I'm sure many after I find conflicting information and was looking for anyone who had trod a similar route before and without going to too much trouble had an answer, e.g. exhaust manifold 8943660210 from a 4BG1T or one from a 4BD2 fit, but maybe have a different flange size etc.

I am totally for the walk in walk out and have no issue with the typical costs for the turbo kits, I agree it is also their intellect that is part of the price and as a business they are there to make a profit. Reality check is for me my current situation doesn't allow me that luxury.

Thanks again

Ted


Series 2A ute
GS daily drive
GS in the shed for the above surgery!

[Phil B]

Ted
I went down the same route as you are exploring and in the end decided to buy and install a kit.
I just found there was too much conflicting opinion about the parts, specs etc to make a sensible decision on a way forward with a self build.
Mine went together easily and has performed well over the last 3 years. I didn’t want rubber burning power, just better tractability and reliability which I got. In fact I have detuned mine slightly to lower EGT’s.
More than happy.
Good luck which ever way you decide to go, you won’t regret how a turbo wakes up the 4bd1

[Blknight.aus]

After many years following some fabulous posts I too want to join the 'try it myself turbo' on my 1988 4BD1 (cost is a large part of it verses drive-in drive-out!) and like others I can wield a spanner but I'm not a garage wizz! Going for a HE221w and standard manifold... however first stumbling block was genuine exhaust manifold 8943662470 is no longer available through Isuzu dealers at $280 - $320, back to full at $600 - $650 + gst unless anyone knows different? If I go down the China route has anyone got a recommendation from personal experience as I know quality, durability and fit varies hugely [bigsad] Opposite to that has anyone had a flash cross-over manifold made up that takes the Holset 5.5cm, supplier, cost? And any thoughts on a few spare part numbers I haven't been able to find; engine gasket set I had was 5878104620 and appears only as Eazyparts 2A6006, is this correct or are there others? Also is there a part number for the oil feed pipe from block to alternator, is the rubber hose by the bypass hose on the pump just standard hose contorted to fit up to the heater pipe or is there a part number? and does anyone know a supplier for the alternator pulley? mine came with a twin pulley wheel (probably for an early Patrol or similar) Lots of questions I know, but hoping someone has a few spare moments to fill some of the knowledge gaps[bigsmile1]

Cheers Ted

Series 2A ute
GS daily drive
GS in the shed for above surgery!


My local isuzu parts dealer, HIM can get the manifolds and the gaskets. you'll need a spacer block

[asmit]

Apparently the T25 top mount manifold from the 4BD2 is what some people have used, try some truck wreckers, they might even let you compare/measure the part before you buy it or not.
I would be surprised if you engine related part numbers are not in here: https://www.remlr.com/documents/RPS/02188%20-%20110%20GS/02188-1.pdf
I also agree with everything Phil said :)

[p38arover]

My local isuzu parts dealer, HIM can get the manifolds and the gaskets. you'll need a spacer block

What is the spacer block for?

[Red90]

The kits are not expensive. They are just not using cheap parts. You get what you pay for.

IMO you are asking too many questions to be able to do a quality job and you will have endless problems because of it.

[Blknight.aus]

What is the spacer block for?

depending on which variant of the he221/he31 you get the compressor housing will foul the manifold. Its also a really good place to tap up and setup the EGT probe. and 8mm is enough but a 10mm makes tapping the egt probe in a little less stressful.

I've also had an issue where the provided studs had too much unthreaded shank on them and the nuts wouldnt tighten up.

[rar110]

What is the spacer block for?

The most popular Isuzu manifold is the one used on the 6x6, with 45 degree flange which I believe is a T3 flange. Many popular turbos have the smaller T2 flange. So an adaptor plate needs to be used.

The 6x6 used a T25 turbo so I assume they required an adaptor plate.

[asmit]

The most popular Isuzu manifold is the one used on the 6x6, with 45 degree flange which I believe is a T3 flange. Many popular turbos have the smaller T2 flange. So an adaptor plate needs to be used.

The 6x6 used a T25 turbo so I assume they required an adaptor plate.

No adapter plate on the 6x6 motor, the T25 turbo has a T3 intake flange.

Apparently the 4BD2T motors use a exhaust manifold with T2 flange.

[123rover50]

When fitting a Turbo to the 4BD1 should the head bolts be re-torqued to turbo specs?
if so , should they be removed and lubed with moly or just cracked loose and tightened?
What specs and should it be the 2 stage method? I have read different opinions?
My memory is not what it used to be.
Thanks.
Keith

[Bazzle218]

When fitting a Turbo to the 4BD1 should the head bolts be re-torqued to turbo specs?
if so , should they be removed and lubed with moly or just cracked loose and tightened?
What specs and should it be the 2 stage method? I have read different opinions?
My memory is not what it used to be.
Thanks.
Keith


When i fitted my Turbo kit there was no mention of re torquing the head bolts. I have had 24 months of trouble free driving including towing a trailer up to the cape twice. I would leave well enough alone. My opinion.

[Bearman]

When fitting a Turbo to the 4BD1 should the head bolts be re-torqued to turbo specs?
if so , should they be removed and lubed with moly or just cracked loose and tightened?
What specs and should it be the 2 stage method? I have read different opinions?
My memory is not what it used to be.
Thanks.
Keith

Certainly wouldn't hurt to check them Keith. 2 stage + angular, I can't remember the figures but I can look them up for you later if you want.

[123rover50]

I have done a fair few K,s already . Out to Birdsville and the Hay River track last winter and not worried about it. Its only recently I read that the turbo has different torque figs to the NA and the studs should be lubed with moly whereas the NA is lubed with engine oil.
Can the studs be used more than once or does that last turn stretch them and we need to use new ones?
Now its not NA anymore do we treat it like a turbo?
Back in the day lots of people were putting turbos on NA 4BD1 engines and I was wondering if they retorqued or just let things be.
I am inclined to just let it go as its going well just now.
See if I get any other replies.
Keith

[Zcoota]

I didn't re-torque mine and ended up with a gasket failure. It was odd, if I drove around off boost I didn't have any problems but if I used the turbo (about 18psi max and temps no greater than 550) it would pressurise the cooling system. I inspected and re-used the existing head bolts and two stage + angle torqued them and have no problems.

[steveG]

Out of interest - what’s the procedure for retorquing?

I’d guess you do one bolt at a time as loosening them all at the same time would probably break the seal on the gasket?

Steve