[michaellone]

I have come across a pair of turbos and a MSD Marine Boost Timer from an old turbo setup (The price is right!). Help figure out what I have and if it would be a good fit for my motor.

2 Rajay Turbos (3AJ1EE13B1)

I know that the turbos were recently rebuilt by the previous owner and have no time on them.

My current motor is:
454 (.030 over)
Billit splayed mains
Forged Crank
Scat H-beam rods with L-19 bolts
TRW pistons (9.4 compression)
Chevy 820 iron heads
Torquer 2 intake
Holley 850 carb
MSD 6AL
MSD distributor

Goal: 800+ hp on pump gas (E-85 is available in my area)

Any help you guys can give on this is appreciated. I just trying to get some info first. Thanks.

 

[michaellone]

After doing some web searching, I found this our about the turbo:

"That rayjay is a 301 series with a E compressor and an E turbine, and a 1.0A/r. Its flow map is identical to a AiResearch T04b with a V1/V2 compressor."

Not sure if this helps....

 

[IMPATIENT 1]

pm hass828 he's got a pair of rayjays kinda like those on his stealth and is making some very good power with em.

 

[Hass828]

Those turbo's are basically the same as the t04's that I'm running. I started out with a set just like'em. They are expeensive to have redone so when you wear them out you most likely end up with a set of to4s to replace them with. Much more cost effective. They should make 15-20psi easily and make your goal. I'd run the e-85 if available. It'll allow you to lean on it harder and get more out of it. My .02

 

[michaellone]

Thanks for the input. Going to do some more digging so I know what I am getting into.

 

[michaellone]

After doing some reading, I am getting a better understanding on how this setup works. Now I think I know enough to ask intelligent questions.

The two things I have not been able to find out is wastegates and blow-off valves.

How do I tell what size I need for my application?

Are the ones on ebay worth buying or do I need to spend $300+ per valve to get the name brand ones?

I assume that I need a wastegate mounted right before each turbo and a bov before the turn-down going in to the carb. Is this the correct way to manage my boost?

Hass828, you said that I should make 15-20psi easily with my setup. Is there any problem turning down the boost (5-7psi) until I get everything sorted out?

 

[IMPATIENT 1]

After doing some reading, I am getting a better understanding on how this setup works. Now I think I know enough to ask intelligent questions.

The two things I have not been able to find out is wastegates and blow-off valves.

How do I tell what size I need for my application?

Are the ones on ebay worth buying or do I need to spend $300+ per valve to get the name brand ones?

I assume that I need a wastegate mounted right before each turbo and a bov before the turn-down going in to the carb. Is this the correct way to manage my boost?

Hass828, you said that I should make 15-20psi easily with my setup. Is there any problem turning down the boost (5-7psi) until I get everything sorted out?

those turbos are way past their efficiency in the map by 15lbs of boost

ebay ics and gates are fine, i'm runnin a 60mm gate and 50mm blow off on my 325. i put 2 50mm gates and 1 50mm blow off valve on my uncle's 496. wastegates are something its just better to go alil bigger than needed on, it'll make controlling boost easier. go for a pair of 50mm or bigger wastegates, at least a 50mm blow off valve if you plan on doin blow thru. if you're gonna use the system as a draw thru, blowoff valves are a bad idea, ya don't want hot compressed fuel charged boost being blown outta the motor, may hit the headersst

 

[michaellone]

Yes this will be a blow-thru system. Looking to Quick Fuel for the carb and Race Pumps for the fuel system.

I don't understand how to read the maps, what level of boost will are they the most efficient? With my motor, what rpm can I expect to reach that level?

 

[Unchained]

Before you start down the turbo path be sure you review what your ultimate goal is. There are a lot of the Gale Banks kits around and they seem to do a fair job for around the 800 hp level. If that's good enough for you then fine.

If once you get a taste of turbo's and you want to put out 1200 hp (and you will) then you will have to start over again. Those 53mm turbos are at their limit already. They become a bottleneck in the exhaust where more boost won't make more power. Even the manifolds are too small to mount a big turbo on.

 

[beaverfab]

What type of boat? Jet, v drive or outdrive, flat, v or something diferent. I have a PFM set up in my 18' flat and it is a Bitch to drive. Just my .02 thanks j.j.

 

[michaellone]

It's a 81 Hondo Ski Hydro. As far as my long term goals... Pro Mod Drag Boat! Don't know if I will ever get there, but if your going to set goals... set them high.

I am guessing that I am making 500-550 hp on motor alone. So stepping up to 800 hp will be a decent change. After I get this setup working, I will start working on new bullet and have this as my back-up.

 

[Hass828]

After doing some reading, I am getting a better understanding on how this setup works. Now I think I know enough to ask intelligent questions.

The two things I have not been able to find out is wastegates and blow-off valves.

How do I tell what size I need for my application?

Are the ones on ebay worth buying or do I need to spend $300+ per valve to get the name brand ones?

I assume that I need a wastegate mounted right before each turbo and a bov before the turn-down going in to the carb. Is this the correct way to manage my boost?

Hass828, you said that I should make 15-20psi easily with my setup. Is there any problem turning down the boost (5-7psi) until I get everything sorted out?

No problem at all, just get a set of 46mm waste gates with the 4lb springs and you'll be able to turn it down just fine.

 

[Hass828]

those turbos are way past their efficiency in the map by 15lbs of boost
ebay ics and gates are fine, i'm runnin a 60mm gate and 50mm blow off on my 325. i put 2 50mm gates and 1 50mm blow off valve on my uncle's 496. wastegates are something its just better to go alil bigger than needed on, it'll make controlling boost easier. go for a pair of 50mm or bigger wastegates, at least a 50mm blow off valve if you plan on doin blow thru. if you're gonna use the system as a draw thru, blowoff valves are a bad idea, ya don't want hot compressed fuel charged boost being blown outta the motor, may hit the headersst

What ever you do dont listen to this guy

Those T04B turbos are right in the middle of the efficiency island on the map at 15-20 psi and WILL work just fine, especially if your going blow through. You should be able to get 800-1000hp with a good intercooler and tune up.
Like Mark said though, when the day comes to go beyond that(and it will) , then you'll want to go up to a set of T6 large frame turbos and a set of Marks headers, then the sky's the limit on hp.

Oh yea, on some of those 301E Rayjay turbos that came from banks and pfm, they had a hole drilled though the turbin housing on the exhaust side that was used to limit boost. It was the size of the hole that determined the amount of boost available--the smaller the hole the more boost. So be sure to look'em over to see if they had the holes. Also may be able to get away without waste gates if you can get some info on what size hole to drill(&were) to limit your boost. There's a guy on here that goes by obnoxiuos 1 that used to work for Banks in the hayday of these kits, he should be able to help you out with the info.

 

[obnoxious001]

Oh yea, on some of those 301E Rayjay turbos that came from banks and pfm, they had a hole drilled though the turbin housing on the exhaust side that was used to limit boost. It was the size of the hole that determined the amount of boost available--the smaller the hole the more boost. So be sure to look'em over to see if they had the holes. Also may be able to get away without waste gates if you can get some info on what size hole to drill(&were) to limit your boost. There's a guy on here that goes by obnoxiuos 1 that used to work for Banks in the hayday of these kits, he should be able to help you out with the info.

Pretty funny,, I was going to comment about the bypass holes,, but down here at the bottom of the thread you have it.

Look in the bottom of the turbo, through the square flange and there is most likely a hole,, somewhere between 1/4" and 1/2". That was the way they limited boost back in the 70's with those kits. If you want to use waste gates, it is possible to tap the holes for pipe plugs, or if you wanted to reduce the size of the bypass as well,, depending on what you already have.

 

[michaellone]

Thanks for the heads up on the bypass holes. I will get some more pics of the turbos tomorrow and look for the holes.

For the intercooler, I have been seeing these on ebay and a lot of turbo sites. I assume that they are a Chinese knock-off. Found this one on E-bay for $70. Any known issues with them?

http://cgi.ebay.com/ebaymotors/ws/e...0fffc1adb&rvr_id=&ua=WXS?&itemid=230402269853

I was thinking running one for each turbo. Plumb the water out of my Magnaflow to the bottom of the cooler and then from the cooler to the block. With lake water cooling the air charge, that should keep the temps down.

 

[IMPATIENT 1]

What ever you do dont listen to this guy

Those T04B turbos are right in the middle of the efficiency island on the map at 15-20 psi and WILL work just fine, especially if your going blow through. You should be able to get 800-1000hp with a good intercooler and tune up.
Like Mark said though, when the day comes to go beyond that(and it will) , then you'll want to go up to a set of T6 large frame turbos and a set of Marks headers, then the sky's the limit on hp.

Oh yea, on some of those 301E Rayjay turbos that came from banks and pfm, they had a hole drilled though the turbin housing on the exhaust side that was used to limit boost. It was the size of the hole that determined the amount of boost available--the smaller the hole the more boost. So be sure to look'em over to see if they had the holes. Also may be able to get away without waste gates if you can get some info on what size hole to drill(&were) to limit your boost. There's a guy on here that goes by obnoxiuos 1 that used to work for Banks in the hayday of these kits, he should be able to help you out with the info.

yeah, don't listen to the guy who actually can read a compressor maphil i don't think you've seen the map on your own turbos, cause you're wayyyyyy past the surge lines on those

its all in the map man, sure you can take a small turb and overspeed it like hass does and get 15lbs of boost, but once that turb is moving the 50lbs of air that its only gonna move, anything else is stacking hot boost and is inefficient, no matter what the boost gauge says.

 

[Unchained]

yeah, don't listen to the guy who actually can read a compressor maphil i don't think you've seen the map on your own turbos, cause you're wayyyyyy past the surge lines on those

Uh ...... I believe the surge area is at on the bottom (left) side of the map, not at the top end. You risk surge with way too large of a turbo, not too small.

 

[Hass828]

yeah, don't listen to the guy who actually can read a compressor maphil i don't think you've seen the map on your own turbos, cause you're wayyyyyy past the surge lines on those

its all in the map man, sure you can take a small turb and overspeed it like hass does and get 15lbs of boost, but once that turb is moving the 50lbs of air that its only gonna move, anything else is stacking hot boost and is inefficient, no matter what the boost gauge says.

Show's that you dont know a damn thing about me or what I know. I didnt just "get lucky" that my setup works, and I didnt have to call everbody in the country for advice on what to run like you guys either.

Heres a link to the comp map in question. http://www.turbofast.com.au/FlowTO4B.html
Look at the second map down the page, this is a map of a T04B, V1-V2 trim. same thing I'm running and very simular to the map of the 301E that is refered to above.
Now, if you take a 468cid engine in N/A form , it will use 730 cfm at 7000rpms at 80% eff(according to the graph in my turbo book) which is were "most" N/A engines opperate.
Then you have to go to another graph to figure your density ratio because the turocharger squeezes the air down considerably from abient conditions, this chart is necessary to calculate the amount of air entering the compressor.
All centrifugal-comp. Maps are based on inlet conditions. To use the chart it is first necessary to convert boostpressure to pressure ratio. heres how its done.
Ambient press. + Boost Press./ ambient press.=PR

Assuming the engine is to be run at app. 1000ft altitude where the ambient press. is 14.3 it would look like this
14.3+15/14.3 =2.04PR
then if you look at the density ratio chart you will find that you will have a density ratio of about 1.53.
So you take your N/A cfm x your DR of 1.53 =1116.9cfm at 7000rpms w/ a PR of 2.04.
Now to convert cfms to lbs/min you multiply by 0.069 to obtain the correct flow because most lb/min comp. maps are created by running the turbocharger compressor at 85F and 28.4-in hg press.
So, 1116.9cfmx.069=77lbs/min.
Then you divide by 2 because you have two turbochargers and you get 38.5lbs/min at a press. ratio of 2.04.
Now lets look at that map.
Looks like 71% efficiency to me, and nowhere near the surge line like dipsh-t was tring to suggest.
And if you go to 20lbs of boost and redo the math you wind up with 41lbs/min and a press. ratio of 2.41, still at 71% efficiency on the map.Actually a little closer to 72%.

So go back and learn some more about this turbo stuff before tring to blow smoke up everyones azz that after a few months of messing with this stuff that all of a sudden your an expert on turbo selection. Dip sh-t

 

[michaellone]

Hass: Thanks for crunching the numbers! I don't full understand all the math, but I am learning.

If I am reading the map correctly, the most efficient this turbo can be is 73%?

 

[Outlaw]

Show's that you dont know a damn thing about me or what I know. I didnt just "get lucky" that my setup works, and I didnt have to call everbody in the country for advice on what to run like you guys either.

Heres a link to the comp map in question. http://www.turbofast.com.au/FlowTO4B.html
Look at the second map down the page, this is a map of a T04B, V1-V2 trim. same thing I'm running and very simular to the map of the 301E that is refered to above.
Now, if you take a 468cid engine in N/A form , it will use 730 cfm at 7000rpms at 80% eff(according to the graph in my turbo book) which is were "most" N/A engines opperate.
Then you have to go to another graph to figure your density ratio because the turocharger squeezes the air down considerably from abientconditions, this chart is necessary to calculate the amount of air entering the compressor.
All centrifugal-comp. Maps are based on inlet conditions. To use the chart it is first necessary to convert boostpressure to pressure ratio. heres how its done.
Ambient press. + Boost Press./ ambient press.

Assuming the engine is to be run at app. 1000ft altitude where the ambient press. is 14.3 it would look like this
14.3+15/14.3 =2.04PR
then if you look at the density ratio chart you will find that you will have a density ratio of about 1.53.
So you take your N/A cfm x your DR of 1.53 =1116.9cfm at 7000rpms w/ a PR of 2.04.
Now to convert cfms to lbs/min you multiply by 0.069 to obtain the correct flow because most lb/min comp. maps are created by running the turbocharger compressor at 85F and 28.4-in hg press.
So, 1116.9cfmx.069=77lbs/min.
Then you divide by 2 because you have two turbochargers and you get 38.5lbs/min at a press. ratio of 2.04.
Now lets look at that map.
Looks like 71% efficiency to me, and nowhere near the surge line like dipsh-t was tring to suggest.
And if you go to 20lbs of boost and redo the math you wind up with 41lbs/min and a press. ratio of 2.41, still at 71% efficiency on the map.Actually a little closer to 72%.

So go back and learn some more about this turbo stuff before tring to blow smoke up everyones azz that after a few months of messing with this stuff that all of a sudden you an expert on turbo selection. Dip sh-t

Good information,