Garrett/Air Research Turbo Help

curts56

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I have an Air Research/Garrett turbo from my old (1979) Ak Miller 240-300 turbo kit. The kit lists the turbo as:

Model TO4B30 turbocharger with "V-1" trim compressor and 0.81 A/R "P" trim turbine housing.
Part #409900-5001

Somewhere (this forum?) I read that the compressor A/R was 0.60, but I don't have the actual specs.

Any idea where I could get a compressor map for this turbo? I'm in the process of putting a 300 together using this kit and I'd like to get an idea what Ak was thinking. Unfortunately Ak is no longer around. :(
 
The V1 trim should be 55mm compressor inducer and 70mm exducer.
That should be real close to a GT3071R compressor map.
 
curts56

Its not where it should be,

instead look at

See fig 7, the T04 v1/v2 map

http://www.turbocharged.com/catalog/compmaps/fig7.html

or http://www.not2fast.com/turbo/maps/all.html

Here,

its under
Board index
Inline Performance
144-250 "Small Block" Six Performance

"What size turbo do I need?" #1 by Dantheman67 » Wed Dec 14, 2016

in post Hash 12 (#12)

viewtopic.php?f=1&t=76010&p=585330#p585330

Generally, the 2.0 to 2.3/2.4 liter guys use these turbos in OHC 4 cylinder Pinto, Lima, or 240SX in 0.69 AR form. AR listed is the turbine AR.

0.69, not 0.68 (Lincs200 et al have repeated this mistake..)

General info, care of Lincs200 in this chart, 5th and 6th rows in Post #7 viewtopic.php?f=1&t=76010


113_0312_turbo_15_z.jpg



xctasy":ugs5sxt5 said:
........

From page 133, Chapter 11 Turbocharging & Supercharging

How to Modify Fords OHC Engines by David Vizard

https://www.scribd.com/doc/26804743/How ... ard#scribd

in 1977, David Vizard exclusively used Ak Miilers TO4 V1 Turbo kits on most of his Doug Sommerville sponsered Turbo 2.0 SOHC Pinto dyno tests. Sometmes, they got downgraded to an older kind of E1 trim TO4, but that shouldn't concern us here.



DV_chapter_11_page_133_fig 11_1a_FLOW_MAP_FOR_ AIRESEARCH_ TO4_v1_TURBO

See point A and B

DV_chapter_11_page_133_fig%2011_1a_FLOW_MAP_FOR_%20AIRESEARCH_%20TO4_v1_TURBO.jpg



On a 250-300 hp plus turbo 2.0 Ford engine, reving to 6500 or as much as 7000 rpm, a 320 degree, 284 degree at 50 thou, 560 tho lift Crane 322 B (now FOR 320-10 these days on 2300 Lima engines http://www.cranecams.com/186-187.pdf) cam verses the stock 264 cam was used on the TO4 V1 trim turbo.


This is probably the only case where a surge zone may occur.


On a 200 to 250 Ford six, the same Lincs 200 style turbo will work really good......

the normal small A/R for T4 V1 compressor with a P trim turbine is actually 0.69.

Compressor is actually 55mm

0.69 is standard
0.81 is the next size up.

Its not 0.69/0.81 like it says in theold Hot Rod link above..

often, like drag-200stang found, on a 200 or 250 engine, people can't control boost over 5500 with a 0.69.


If you have acces to a Windows NT, See http://www.turbofast.com.au/javacalc.html


For other computers, See https://www.maperformance.com/pages/tur ... calculator

Note

http://www.freshalloy.com/showthread.ph ... e0b45c0772

https://turbobygarrett.com/turbobygarre ... ing_sizing


And the source of the turbo sizing table, Sport Compact Turbos & Blowers - Page 60

Originally published: September 2004
Author: Joe Pettitt

b10098_turbos_blowers__99126.1339460259.1280.1280.jpg


P60%20of%20Sport%20Compact%20Turbos%20amp%20Blowers%20by%20Joe%20Pettitt.jpg
 
I do not know if this helps anyone but way back when, a.68 was tangential and .69 was on center but things change...with tangential being a little more efficient.
 
Thanks for all the info! So based on the charts the 0.81 A/R "P Trim" turbine would be appropriate for a 300ci engine?

If I recall (25 years ago) my previous 300 with this same Ak Miller setup seemed to pull the best around 3500 RPM, though I probably had the wrong cam and and not optimal ignition timing. With the turbo I have does that seem right? Looks like I have some reading to do.......
 
On a 300 six the ability to make power depends a lot on head porting and cam combination.
How much power are you looking at making?
 
CK ,.
Please tell us about your engine and how you plan to use it....AK was very conservative and practical I am sure that he meant that turbo and ar for a mild low boost daily driver but I could be wrong.
If you are trying to kick the big dogs off the porch, that turbo is too small !
 
drag-200stang":2m041wmh said:
CK ,.
Please tell us about your engine and how you plan to use it....AK was very conservative and practical I am sure that he meant that turbo and ar for a mild low boost daily driver but I could be wrong.
If you are trying to kick the big dogs off the porch, that turbo is too small !

Actually if you look at the Compressor map that turbo can easily make 450-475 HP @ 25 lbs of boost, 400 @ 15 and 325 @ 10
The .81 A/R turbine housing will allow a fair amount of exhaust flow before choking.
The .60 compressor trim also favors higher volumes with reasonable spool time.
The turbo can be considered a good mid range player for a 300 six.
 
Thanks pmuller. That's good to know the turbo should meet my goal, which is around 300HP.

The engine is going in my 56 F100 pickup, This will be the third (and hopefully last) turboed 6 for this truck. I threw a rod out the block of the first engine (turboed 223) . I replaced it with a turboed 300, which ran good for a number of years. But it was already bored out .060 over so wasn't worth rebuilding. It also had aluminum rods which probably were not the best choice for a long lived street motor.

So I'm trying to build an engine that will last, looks cool, and can go fast on occasion. So far I have:

1992 block with very little cylinder wear
~1982 head
Forged steel crank
Crane roller rockers
Isky cam kit (doesn't have the correct cam for a turbo)
Edelbrock 1V intake
Ak Miller turbo setup
Turbonetics 35mm waste gate
Melling HV oil pump
Cloyes cam gears

I plan on getting custom pistons, rods, and camshaft. The head will also be ported. Still kicking around whether to go carb or TBI. Maybe carb to get it running and then TBI. The Ak Miller draw-thru setup isn't optimal, but it's old school and pretty rare so I've decided to use it.

Any suggestions are welcome for cam specs or anything else based on my goals.

Here's a picture of my mockup:

[image]http://www.ckdesign-inc.com/images/Turbo/300-2.JPG[/image]

Seems like this project has taken forever. My wife wants a spot in the garage so I need to get this truck back on the road after sitting in pieces for 23 years.
 
Head porting, custom cam, and all the other goodies you listed will get you 300 hp without a turbo.
That's more like a recipe for 500 to 600 hp with a turbo
It doesn't take much to make 300 hp with a turbo 300 six.

If you build an engine that pumps more air than the turbo can handle then you will have to limit the engine rpm or the turbo will be run past it's safe operating limit.

There is no problem with building a strong bottom end, just be moderate with the head modifications and cam choice.
 
If I can get ~300HP @ ~10lbs boost without porting the head then that would be good. I'd rather keep the boost down and not heat up the air since the draw-through doesn't/can't have any intercooler. I have used water injection in the past and that seemed to take care of any detonation. Just a hassle to keep the water tank full.
 
curts56":2epkoo4b said:
If I can get ~300HP @ ~10lbs boost without porting the head then that would be good. I'd rather keep the boost down and not heat up the air since the draw-through doesn't/can't have any intercooler. I have used water injection in the past and that seemed to take care of any detonation. Just a hassle to keep the water tank full.

OK, Then figure on larger valves, 1.94" intake and 1.60" exhaust. SI valves is your main source for Ford 300 valves.

Optional if you are handy with a grinder?
Before the valve job, narrow the boss around the valve guide, do some port cleanup and smooth out the combustion chambers.
After the valve job very carefully blend the throat area below the seat (where the lower angle was cut for the larger valves) into the bowl area.

Do you still want to use roller rocker arms?
 
I'd like to use the roller rockers since I already have them. They require a 3/8" stud so I guess I need to replace the press-in studs with screw in 3/8" - 7/16" studs. Do I need to machine down the mounting bosses to accommodate the hex portion of the stud?
 
curts56":2izbesih said:
I'd like to use the roller rockers since I already have them. They require a 3/8" stud so I guess I need to replace the press-in studs with screw in 3/8" - 7/16" studs. Do I need to machine down the mounting bosses to accommodate the hex portion of the stud?
You should just be able to pull the studs and drill and thread the holes.
Get the studs that do not have the radius under the hex that is used to locate pushrod guides.
You don't need guides with the 1982 head.
You want the studs to sit flat against the bosses.

What engine was the Crane rockers for?
What ratio are they?
 
The Crane rockers are for the 300. The part number is 50750-12, which is now listed as special order. The ratio is 1.6.
 
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