Does TA-49 need high boost to make power?

[bishir]

I recently installed my TA-49 on my car with a new THDP. Previously, the car had a stock turbo and stock downpipe. I had ran a 8.3 before the install with 22lbs of boost and a 2.0 60ft, and I ran a 8.0 on 20lbs with the TA-49 with a 1.8 60ft and everything else was the same. I was a little dissapointed since I was expecting 7s. Does the TA-49 need mid 20s to make real power? I'd like to turn the boost that high with race gas, but was hoping to run mid 7s in street trim. Maybe I should just tune more... I'll find out next Friday at the track I guess...


James

 

[QuickWrench]

In my experience (2 stock-engined GNs with TA-49's), the TA-49 really has a sweet spot between 21-25 pounds of boost. If you're tuning appropriately and have sufficient octane...yes, the 49 will make appreciably more power at 25# than 20#.

In street trim, it's also a better, more efficient turbo. I've always known the TA-49 to be a no-downsides unit on the street, with more power than the stock unit at any given RPM.

Check my sig' for a '49-based combo. 1/8 mile times were in the 7.30-7.40 range, at 26-27# boost.

 

[turbonatr]

QuickWrench's car is a perfect example of what a TA49 is capable of with good tuning. 116+mph without heads, cam, etc. A car with all the goodies and a TA49 is an easy low 11 second car, no sweat!

When I ran a TA49 on my T, going from 20psi to 25psi was worth about 5mph in the 1/4 which is 50hp at the wheels. It seemed to be pretty happy at 25psi with race gas.

 

[bishir]

Wow, you ran that on DRs too? That's what I was hoping for when I got the 49. No suspension mods?

Thanks,

James

 

[tminer]

I think that you did pretty well. 2 psi less boost probably killed any efficiency gain and you got .3 from the THDP.

It is a vast missconception that just putting on a bigger turbo will make a lot more horsepower at the same boost. One will gain a little because in general bigger turbos are more efficient. The big gains come from running more boost than possible with the smaller turbo or increasing engine VE thru heads, cam, etc and pushing more air MASS.

Tom

 

[bishir]

I'm going to try to make another trip but I'm going to turn up the boost this time. I'm running 20psi on the street with no hint at knock so I might turn up my street boost too. The TA-49 made a dramatic change in midrange pull. It was amazing. I did notice it took slightly longer to spool if I stabbed it from idle without brake boosting. I almost want to sell my 69 Mustang and buy a T-type so I can make a big turbo dragcar just to feel what one of those feels like.

James

 

[GNFURY]

You just can't beat a huge turbo with the right parts accompanying it. street or strip.