fabmec yet another briliant lead. you may have only 10posts but have many more years experience . nice work sir ,better watch your pm box now,lol.
Builds Isuzu 4BD1T Lexus LX450 (Land Cruiser) Build (2 Viewers)
- Thread starter Wheelingnoob
- Start date
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Interesting. Mine's a 7 as well. The large angled housing I have shows as being a -7 as well but is much larger. I want to learn more...can you point to a reference on these guys? Sorry if this is a hijack...
Sorry for a second newbie question...but why would the smaller housing help build boost faster? Seems counter intuitive to me...but I'm sure you all are right...just want to edumicate myself
Smaller turbine housings drive the exhaust harder into the turbine wheel. Spinning it faster, which spins the compressor faster, creating more boost.
Lack of boost also makes diesels run hotter. They do a lot of their cooling through exhaust flow.
The Aussies who are having good results with these turbos are using the 6cm housings.
Jeremy. What's your altitude?
He's pretty much at sea level, perhaps 100m above max at any given time unless he trucks it into the mountains.
- Thread starter
- #924
It's interesting every turbo I have found so far is 7cm, conical straight or angled. I'm surprised volvo guys are spending the money to get the angled 7cm as an upgrade. Only difference is the out let size.
I'm not sure if I should by a 6cm or try and fit a small compound. Would be easyer to fit a 6cm......yeah I'll order one up as soon as I know the cooling is sorted. In the mean time I'm going to turn the fuel back to stock.
Think I'm going to order a oil pump too in hopes that solves my hot low oil pressure. Manual says min 14psi and I'm seeing 5psi after an hour of running, ad the longer than normal delay in pressure building and it points to the pump.
I'm not sure if I should by a 6cm or try and fit a small compound. Would be easyer to fit a 6cm......yeah I'll order one up as soon as I know the cooling is sorted. In the mean time I'm going to turn the fuel back to stock.
Think I'm going to order a oil pump too in hopes that solves my hot low oil pressure. Manual says min 14psi and I'm seeing 5psi after an hour of running, ad the longer than normal delay in pressure building and it points to the pump.
The 6cm2 turbine housing would be a better match for the displacement of the motor I would think, based on experience from the similar cummins cousin. Don't you think that a 7cm2 turbine housing would be restrictive as an atmospheric turbo in a compound setup?
I notice that when I'm running between 1200* and 1300* pre-turbo EGT on the highway for any distance, my coolant temp climbs. EGT is an indicator of load on a motor, so if you're having EGT issues, it would make sense to me that if you fix the EGT issue with a turbine housing that's more suited to your motor, that the cooling problem would resolve itself.
What are the ambient temps up in BC this time of year? When it's 50* and cooler here in North Carolina, my electric fans hardly ever switch on. In fact, it runs so cool during the winter months that I didn't even wire up my electric fans for 4 months and never saw the temp gauge rise above 1/4 on the, albeit inaccurate, factory temp gauge.
I notice that when I'm running between 1200* and 1300* pre-turbo EGT on the highway for any distance, my coolant temp climbs. EGT is an indicator of load on a motor, so if you're having EGT issues, it would make sense to me that if you fix the EGT issue with a turbine housing that's more suited to your motor, that the cooling problem would resolve itself.
What are the ambient temps up in BC this time of year? When it's 50* and cooler here in North Carolina, my electric fans hardly ever switch on. In fact, it runs so cool during the winter months that I didn't even wire up my electric fans for 4 months and never saw the temp gauge rise above 1/4 on the, albeit inaccurate, factory temp gauge.
I figured I should throw my two bits in here. You mention you took off the boost comp on your inline pump.
From when I installed my boost comp I had a decrease in EGTs for sure. It's designed to add fuel accordingly in correlation to what boost level your turbo is pumping out.
I think it's definitely worth your whole to install it and it should help with those crazy egt levels. The along with the proper housing of the turbo you should easily be able to tune max load fuel and get a better/safer driving truck.
From when I installed my boost comp I had a decrease in EGTs for sure. It's designed to add fuel accordingly in correlation to what boost level your turbo is pumping out.
I think it's definitely worth your whole to install it and it should help with those crazy egt levels. The along with the proper housing of the turbo you should easily be able to tune max load fuel and get a better/safer driving truck.
Thanks Dougal! I misunderstood and figured the measurement was of the outlet of the housing and was having a hard time seeing how it would be positive to have a small outlet. I can see how the smaller inlet would increase the air velocity and drive it harder. Thanks!
So what applications did come with a 6cm housing?
I don't think it's just an egt/turbo housing issue for the cooling. I have a similar turbo setup with the fuel screw turned out threeish turns. The EGT's do climb quicker and are only tough to manage like Jeremy said when locked up in overdrive at 53 mph. I don't have cooling issues. I do have boost issues though
If anyone's interested here are some pretty rubbery figures for conversion of cm to a/r ratio, but it gives you a rough idea.
6 cm2 = 0.41 A/R
7 cm2 = 0.49 A/R
8 cm2 = 0.57 A/R
9 cm2 = 0.65 A/R
10 cm2 = 0.73 A/R
11 cm2 = 0.81 A/R
12 cm2 = 0.89 A/R
6 cm2 = 0.41 A/R
7 cm2 = 0.49 A/R
8 cm2 = 0.57 A/R
9 cm2 = 0.65 A/R
10 cm2 = 0.73 A/R
11 cm2 = 0.81 A/R
12 cm2 = 0.89 A/R
- Thread starter
- #929
My pump never had a boost comp, it had an high alt comp. The pumps that did come with them are set up differently than a Toyota, the boost comp simply removes fuel off boost. No profiled fuel pins or spring tension adjusters.
- Thread starter
- #930
I'm sure the 7cm would be restrictive but enough to be noticeable I'm not sure. For now the compounds are on the back burner. I'm going to try the 6cm first and go from there.
My EGT's only hit 1200+ when my foot is into it for a hill and only for a very short time. Cruising along at 100km/hr (60mph) it's about 750-800 and 4-6psi.
When I first got is running and had the overheat issue it was 34c (85-90f) . Since then it's changed to fall and it's in the mid teens now (60's f). Going to be really hard to see if I got the cooling issues fixed. Next time it will be warm will be on my planed road trip with it to moab in the spring. Do not want to find I still have an issue down there.
My own geometry calcs run approx one number higher than yours. I put 6cm at 0.48 A/R and 7cm at 0.56 A/R.
Of course this is only for the TD04HL and HE221 housings of that radius. Step into a different frame size or large enough area that it requires a bigger radius and all bets are off.
The next caveat is all these numbers are meaningless, except for camparison, unless you delve right into the specific wheel geometry contained within the housing and the compressors they are mated to.
The numbers I've crunched suggest you need your big turbine to have twice the choke flow (lb/min corrected flow) as the small turbine. If you have a hunt through garrett catalogues with the turbine maps showing this will give you an idea of the size range you require. I can guarantee a 7cm will be too small for the big turbine on these engines.
If your turbines are too close in size then you can't get enough pressure ratio across the small turbine to spool it up. It needs enough offset for the small one to spool up and then bring in the flow to spool the big turbine.
- Thread starter
- #932
So today there was no work for me so I had a bonus day to work on the truck. I got a lower rad hose that seems to fit better and give me more clearance. I then got a sheet of aluminum to re make the fan shroud minis all the duct tape. Got that done and then started looking at my fans, or more so the clutches. The Toyota clutch is shot the valve that is moved my the thermal spring is sized (tested with a heat gun). So for now I put the locked Isuzu clutch on. I think zi am going to try and find a new Isuzu clutch to replace this one. It seems to fit my shroud better is 1" larger than the Toyota fan and it's easier to get on and off. Anyone know of a good source to get decent fan clutches? Would prefer a name brand an not an eBay special.
Anyways once that was all on I tested my cheap temp gauge and sure enough........
It's was 18-25f off all the way from 150 to 220f that I tested it. So it did not go back in. I'm going to rely on my IR gun and stock gauge for now.
No test drive today since it was rush hour when I got it all bleed. It took much longer today to get up to temp not sure if it's a placebo or if the new rad really is that much better.
I started shaping out my rusty leaking fuel filler pipe today too and figured I would break all the bolts
I have a new filler and have cut out the fuel restrictor. Just need to figure out how to secure it now, can't drill out the broken ones because a frame bulk head is right below it. Kind of a stupid design. Look forward to filling it at the pump instead of out of Jerry cans.
In the next few days I hope to get the filler swapped and test it on the road again.
Anyways once that was all on I tested my cheap temp gauge and sure enough........
It's was 18-25f off all the way from 150 to 220f that I tested it. So it did not go back in. I'm going to rely on my IR gun and stock gauge for now.
No test drive today since it was rush hour when I got it all bleed. It took much longer today to get up to temp not sure if it's a placebo or if the new rad really is that much better.
I started shaping out my rusty leaking fuel filler pipe today too and figured I would break all the bolts
I have a new filler and have cut out the fuel restrictor. Just need to figure out how to secure it now, can't drill out the broken ones because a frame bulk head is right below it. Kind of a stupid design. Look forward to filling it at the pump instead of out of Jerry cans. In the next few days I hope to get the filler swapped and test it on the road again.
- Thread starter
- #933
Oh I may also have solved my EGT issue........ ROOKY mistake I did not have the jamb nut tight enough and it looks like the screw backed off so I turned it back into about the same place it was when I installed it.
so I turned it back into about the same place it was when I installed it.
Hmm wouldn't that give you lower temps if your probe was out of the mid stream? Good that it's in place though.
That cm A/R chart has floated around the net for years and, if I remember correctly, on one evo site it was mentioned that it was referencing the td05h turbine to get those numbers.
To compound and get a true free floating large turbo on your engine would be great, but I doubt you have room for it. If you maximized your HL turbine and later got a larger housing you could use it like a semi sequential / compound and still benefit greatly from it as it would widen your boost window and give you highish boost (30ish) with fairly low tech turbos. Depending on the room you might squeak a td05 in there. Later of course.
That cm A/R chart has floated around the net for years and, if I remember correctly, on one evo site it was mentioned that it was referencing the td05h turbine to get those numbers.
To compound and get a true free floating large turbo on your engine would be great, but I doubt you have room for it. If you maximized your HL turbine and later got a larger housing you could use it like a semi sequential / compound and still benefit greatly from it as it would widen your boost window and give you highish boost (30ish) with fairly low tech turbos. Depending on the room you might squeak a td05 in there. Later of course.
- Thread starter
- #935
It's actually the more fuel screw that backed off so EGT's would be higher.
I have been looking at a TD05 as a larger turbo something in the 8-10cm range, found quite a few that are T3 flanged and non internally gated. Not going to be doing anything for a while though, 6cm turbine swap first.
Hey Jeremy,
I have a virtually brand new Isuzu factory fan clutch if you want it?
Here is a shot of it. Let me know.
I have a virtually brand new Isuzu factory fan clutch if you want it?
Here is a shot of it. Let me know.
- Thread starter
- #937
Yes I do want it Doug. Shoot me a PM of what you want and we'll sort something out.
Thank you!
Ahh I misunderstood bout the screw. Sorry.
Cover the shipping.
PM me the address you want it to go to. I recall shipping some parts to a WA address and the BC recipient crossed the border to PU, as it was way cheaper. Does this work for you?
PM me the address you want it to go to. I recall shipping some parts to a WA address and the BC recipient crossed the border to PU, as it was way cheaper. Does this work for you?
- Thread starter
- #940
Pm sent! Thank you very much!!
