Max boost before heads lift?

[towcat]

i'm surprised noone is talking about maping a turbo's efficiency range yet.
on a unmodded ATS WG w/aftermarket outlet, the peak efficiency is at 8-9 psi. I'm able to get to 8psi with a 15k trailer. 5-6psi is my max unloaded. the fuel screw is bottomed and backed off 1 flat. check my sig line for the rest of the mods. one last thing, with the IC, I don't get past 1100deg. period.

 

[dyoung14]

i'm surprised noone is talking about maping a turbo's efficiency range yet.
on a unmodded ATS WG w/aftermarket outlet, the peak efficiency is at 8-9 psi. I'm able to get to 8psi with a 15k trailer. 5-6psi is my max unloaded. the fuel screw is bottomed and backed off 1 flat. check my sig line for the rest of the mods. one last thing, with the IC, I don't get past 1100deg. period.

is your wastegate un hooked? or do you just have it set to that boost level?

 

[runaway!]

I am having the same problem w/ mounting an intercooler on my truck. I found a small one simIlarin size to what the other guys are running, but the only place it will fit is out under my full replacement front brushguard, which puts it down low where mud and brush would hit it, plush then the intercooler tubes would have to fish under the radiator and back up and around to get back to the engine.

As for the boost question, if the guy yall were talking about is running 30psi no problem then there shouldn't be any reason we can't go up to 20psi or so w/o tearing something up?

Also, just wanted to say I appreciate all the info and discussion, really helps to hear other points of view on things!


Bowedup

I am under the assumption you are bone stock in other areas. Head studs, custom gaskets, o-rings or fire rings, lowering compression - are all things that can be done to run more boost safely.

Concerning the intercooler, you might be able to cram one in by removing the radiator fan and clutch, then get a few electric fans

 

[razorback]

ill probably know what the limit is sooner than later.. the turbo i put on my truck is about twice the size of a banks. it doesnt spool real quick low rpm but when you get on it, it spools quick and that was with the old very worn pump.

 

[runaway!]

Runaway, youre probably right, but I just don't remember reading any posts that said overboosted engine and blew head gaskets? Lord knows I've read posts about every other failure to our beloved old diesels, just this one doesn't come to mind.

Bowedup

Who knows, head gaskets are fairly easy to replace - maybe it will just take some experimentation.

 

[OLDBULL8]

All this talk about blowing head gaskets. Did anyone ever try coating the gaskets with 3 coats on both sides of rattle can aluminium paint? Friend of mine told me this secret just a few days ago. Say's it's impossible to lift the heads off, after being run, without splitting the gaskets. He's been building race engines (gas) since 1950 and maybe before that. Won a lot of dirt track races in sprint cars powered with the old Hudson (can 't think of the name right now) engines. Oh Yeah, Hudson Hornet. Hey the guy is 88 yrs. old now. They let him drive an S-10 (?) truck in the races at Waynsfield OH. for his 85th birthday, came in second. Right now he is building a 4 cyl. he is expecting to develop 300 HP. for the trucks. Say's it has 275 lbs. cold compression at cranking speed. Maybe someone knows him that lives around Waynsfield OH. He don't do Diesel's but knows alot about them.

Oh yeah, he ******* about that race cause it cost him $560 for helmet and suit to race.

 

[towcat]

is your wastegate un hooked? or do you just have it set to that boost level?

i have it set to roughly 9psi.

 

[runaway!]

All this talk about blowing head gaskets. Did anyone ever try coating the gaskets with 3 coats on both sides of rattle can aluminium paint? Friend of mine told me this secret just a few days ago. Say's it's impossible to lift the heads off, after being run, without splitting the gaskets. He's been building race engines (gas) since 1950 and maybe before that. Won a lot of dirt track races in sprint cars powered with the old Hudson (can 't think of the name right now) engines. Oh Yeah, Hudson Hornet. Hey the guy is 88 yrs. old now. They let him drive an S-10 (?) truck in the races at Waynsfield OH. for his 85th birthday, came in second. Right now he is building a 4 cyl. he is expecting to develop 300 HP. for the trucks. Say's it has 275 lbs. cold compression at cranking speed. Maybe someone knows him that lives around Waynsfield OH. He don't do Diesel's but knows alot about them.

Oh yeah, he ******* about that race cause it cost him $560 for helmet and suit to race.

Can't say I've ever heard of that trick, but I do know that the head bolts are a weak spot in the design, and will stretch - effectively wrecking the gasket. I imagine there would be some warping of the mated surfaces if some dangerous boost numbers were applied.

Anyone know how much you can torque down on ARP head studs? I would think this would be the limiting factor to higher boost.

 

[safd1919]

i was told arp studs are rated at like 150,000 psi but like i said it what i was told

 

[bowedup2003]

Guys this is the info I was looking for!!!!! So we now know that at least some guys are running 20+psi of boost on stock internals, and that a S400 sized turbo may have some lag but our IDI's will spool one up! Now the only question is the longetivity of these setups!

In my mind this info just opened up a whole new area of upgrade oppurtunities! The more I read the less crazy my twin turbo idea sounds!

For the gentleman w/ the S400, did you mount it up to the stock turbo mount or fab a custom mount? Do you have any pictures of your setup?

Has anyone else tabbed in a custom turbo setup?

Thanks guys!

Bowedup

 

[runaway!]

Just a side note for your consideration:

Based on what I've read, a non WG turbo has a larger outlet and thus will take a bit more to spool up. This is why they typically won't need a WG as they will less likely create the scenario of overboosting under load.

By using a setup with a WG, a turbo will spool quicker (which is what we want on an IDI) and get the boost lower in the power band (which is where an IDI shines).

I imagine using a reducer after a turbo, with an external WG might solve the turbo lag issue of a large turbo.

 

[dyoung14]

All this talk about blowing head gaskets. Did anyone ever try coating the gaskets with 3 coats on both sides of rattle can aluminium paint? Friend of mine told me this secret just a few days ago. Say's it's impossible to lift the heads off, after being run, without splitting the gaskets. He's been building race engines (gas) since 1950 and maybe before that. Won a lot of dirt track races in sprint cars powered with the old Hudson (can 't think of the name right now) engines. Oh Yeah, Hudson Hornet. Hey the guy is 88 yrs. old now. They let him drive an S-10 (?) truck in the races at Waynsfield OH. for his 85th birthday, came in second. Right now he is building a 4 cyl. he is expecting to develop 300 HP. for the trucks. Say's it has 275 lbs. cold compression at cranking speed. Maybe someone knows him that lives around Waynsfield OH. He don't do Diesel's but knows alot about them.

Oh yeah, he ******* about that race cause it cost him $560 for helmet and suit to race.

you mean aluminum color or like aluminun like it has aluminum in it?

 

[razorback]

i had a banks turbo on there, so all i did was cut off the part that goes back up to the turbo and welded some pipe to extend it back under the truck and by the transmission, then weld on the t4 flange and route the cold side up to the intake. its about right under passenger side, with the exhaust side coming out on the drivers side. its pretty much about 5 ft of 4 inch exhuast tubing.. its LOUD, it sounds like a semi turbo spooling at times. i did just recently put on a BOV because i had, what i think was compressor surge due to so much air being pushed by turbo, if it doesnt work ill just take it off and sell it. i can hear turbo spool between 1k-1500rpm unloaded on a small hill i got up to around 10psi. ill try to find a pic of the setup i have, f250 (forget exact name) has a similiar setup only using a dt466 turbo which is smaller than mine. i only paid 300 for the turbo new so its not like i would be out alot if it didnt work. i REALLY need to put headstuds on though.


i found a size comparison of turbo, i had one of the turbo right beside the old banks just cant find it right now.

You must be registered for see images

 

[OLDBULL8]

you mean aluminum color or like aluminun like it has aluminum in it?
I think all the aluminum paint has either powder or small flake in it.

 

[OLDBULL8]

Can't say I've ever heard of that trick, but I do know that the head bolts are a weak spot in the design, and will stretch - effectively wrecking the gasket. I imagine there would be some warping of the mated surfaces if some dangerous boost numbers were applied.

Anyone know how much you can torque down on ARP head studs? I would think this would be the limiting factor to higher boost.

Yeah: ARP studs or similar would be a requirement, even on gasser's.

I think I read somewhere the ARP studs torque to 150 ft.lbs.