I bought a BBS turbo header system (Turbo header, crossover, driver's shorty) for a TPI Serpentine system WITH AC... It's a black car, I live in Florida and NO, I'M NOT GETTING A 350!

Anywho, Ed said due to size restrictions, where it is, keep stock hood, I would need a T04 60 .96 turbo...

I understand the T4/T04 flange.
I understand the 60 is the compressed size out.
I understand the .96 is the exhaust side size...

Currently I have a 305... and I would use it boosted...
I have other nice parts I've bought along the way (wanted them / got good deals), such as Edelbrock TPI base, TF 175 heads, AS&M runners...

But from what I'm reading, due to turbo size, it's best to keep the stock sized stuff if I want to turbo the 305...

I know TurboTPI was using a 62 1 turbo on his 5.7, different cam, ported vette aluminum heads and got 570 rwp on 13 lbs or boost...

I'm not really sure what this size turbo can do... it would be a street car, not drag...

Any advice would be appreciated...

 

Car would probably go 12's or 11's with an adequate trans, rear, and traction. Just a wild guess though.

 

Street tires... Astro A5 5 speed, McCleod 500 hp clutch / plate, tons of suspension, refreshed 10 bolt with 28 spline axles, Eaton True Trac, Solid Spacer, Cap studs, LPW Cover, Brace kit, tubes welded, etc...

But i need to know about the intake / heads stuff... don't use the free flowing stuff?
Would that make the turbo work harder?
500 RWHP would be the goal...

 

I dont see a 60-1 making 500 whp as a single turbo setup

Not sure where they mount the turbo but i dont see keeping ac with a turbo large enough to make 500 whp. You'd need atleast a T4 70mm which is too big to fit in enginebay. I have one and a 305 tpi ac car that i'm gonna turbo but not sure how yet

 

What Ed recommends if you want to go bigger, get the V Belt BBS Turbo Header and switch to V belt (from serpentine) if you want bigger turbo and want to keep your AC.

Rafael

 

Yeah that is a baby turbo. I dont see more than 350 whp but could be wrong lol my t4 70 wouldnt fit there easily and i think its taxed at 500 whp.

I have twins 70's on the big motor and seem to be pushing limits of turbos at 500 whp per bank by the iat rise but my cooler is smaller so hope to have another 100-150 hp left in each

 

350 RWHP is still better than stock...
The torque would still be up due to the TPI, correct?
Better to stick with stock stuff since the turbo is tiny?

 

If turbo keep the cam smaller. Heads will still help power somewhat

You will want to somehow get an air intake on that turbo to some cold air source. And heat wrap/insulate the ac system components

 

I thought of using a t4 with my build, 330-350whp out of my LTx 305 is the goal but im leaning more towards a HX40 or a GT45(swap over to a lt1 and can still use the GT45). Id be more worried about the bottom end before I worried about the heads/cam. I read a while back about a stock LG4 put down 300whp with a HX35...didn't last long before a piston or two went.
Though Im not planning on keeping the A/C in mine.

 

Can someone clarify why....

a 62 1 (assuming 62mm ar and 1 exhaust) can make 570 RWHP on a 5.7 @ 13 lbs of boost...

and why...

a 60 .96 (2 mm smaller ar and .04 smaller exhaust) you guys are estimating at 350 RWHP on a 5.0?

Is it really that big of a difference?

 

T76 would fit no?

I'm running a T76 under my stock hood, and it did fit the knock off BBS header (before I re-did it). Flows 750lbs in the 70% area, should make over 500whp.

In fact, it would probably be better on a 5 liter than my 6.8 liter, no?



-- Joe

 

If the 60 .96 can do around 350,
the 62 1 would be more than enough for my needs...

It does sit at an angle over the passenger valve cover....

Rafael

 

It would on a normal bbs header but does not look like it will on the ac header pictured above

 

Not sure. I am very surprised at how much power his 62-1 is making to be honest. I wouldnt expect a mid 60's mm comp t4 to make that much on that many cubes as a single turbo. Let alone a single 62-1

Looking for 60-1 maps i just dont see them as a good fit for big power on a 305. Your looking at a 200 whp gain over stock bolt on tpi 305 power to get 400 whp. Maps favor larger comp wheels. The math on pressure ratio and airflow required is showing middle area pressure ratio and right side of map for airflow. Those smaller turbos work best at higher pr's and less flow as in smaller cube motors

62-1 would be a better fit if it fits the space.

 

Yeah... and how 2mm and .04 difference is accounting for 200+ HP...

I see some sellers stating that the 60 .96 T04 can make between 425 and 625..... but that's not flow maps...

Maybe it's TPI magic ???

 

http://www.himni-racing.com/turbocha...-p-trim-600-hp

http://www.full-race.com/store/turbo...0-1-turbo.html

http://www.atpturbo.com/mm5/merchant...egory_Code=TBN

http://banzai-racing.com/store/Garrett_60-1.html

I see some say:
- Wheel: 60-1
- Housing A/R: .70 A/R

I think BBS said 60 AR... so that one is too big... ?? Confused...

 

I havent found exact dimensions on the wheels. I dont think its 2 mm difference but could be wrong. Also depends which brand model you go with and the turbine side.

It very well could make 400 whp but to me its not the best turbo for that job. I would prefer alittle larger.

Look at zz3astro build. Hes had a few 60-66 mm type t4's and hasnt gotten over 500 whp i dont think on a 350 motor and lots of boost

 

60-1 seems to be 58-59 mm inducer 76 exducer
62-1 seems to be 62 mm inducer 76 mm exducer, so slight more flow for the 62-1

 

I'm reading that the 60-1 is a 60 mm....
So how is a 62mm producing 200+ more HP?
Again, TPI s not high reving...
I sent Garret and Turbonetics and email... I'll post what they say...

 

I think astro did get over 500 with a precision 6766 but I dont remember how much it made. Maybe he will chime in.....

 

Found it on youtube. He made 532whp with the precision.

 

Precision 6766 is a 67mm....

 

Is your goal still 500+ at the wheels?

 

My goal is to find out what the intended turbo that fits the header I have will do on the header...
Then decide from there...

I am at the Y in the road... I still need a few parts... cam, rollers, etc...(that will work with either turbo or NA)....

 

Its not a guarantee that the 60-1 is 350 hp and the 62-1 is 200+ more hp with 2 mm more turbo.

I have no way to tell exactly what each is capable of without an accurate flow map.

I just known if i wanted more than 400 whp on a 305 sbc or larger, i wouldnt use anything smaller than a good t4 frame in the mid 60's mm if using modern tech wheels or a 70-76 mm using old china type wheels found in ebay units.

500whp is taxing those small turbo hard. Its usually not a good idea to push a turbo at its choke and speed limits to make power

 

What are you running for the heads and cam?
Stock 305 TPI with the larger stock cam (203-ish duration) and a couple of ebay t4/t3 .63 A/R stage 3 twins ($125 turbos) starts to spool at 2500 rpm and makes 12 PSI at 3400 rpm. Holding the throttle steady to make 5 psi it hits the surge region.
Equating the twins to a single comes out to a 76mm compressor and the turbines are bigger than a T4 in terms of inlet area. They spool quick but the surge is not good. WOT they have no surge.
If I had a choice for a single I would go with something in the 66 to 70mm range if using stock parts. If using the parts you listed in the first post then maybe as large as the 76mm.

 

And if you have read turboedtpi's update thread last year he went to a 76mm and car felt much faster on same boost but blew transmission apart. Havent seen an update since

 

Orr... hit the nail on the head a few posts back, it's got to do with the compressor map. Turbos have ranges that they're most efficient in, and when you get outside of that range the efficiency drops off dramatically. This BS that people post "This turbo is good for XXXhp," is just wrong, or more accurately, that's what it can flow enough airflow for at one specifc density ratio. It might be able to flow 500hp at a PR of 2.5 (~21psig boost) and only 300hp worth at a PR of 1.5 (~7.5psig). Typically, by design a lot of the turbos we're talking about flow more air at pressure ratios that are on the high end for a gas engine, and map width enhancement features can help that but hurt the overall efficiency of the turbo everywhere.

The end result is that if have a well matched combination making 500hp at lets say 16psig, and then put the same turbo on a larger engine, or even the same engine with a better breathing head or larger cam so it _should_ make the same power at 10psig, you might find that now that turbo can't flow enough at that ratio to feed 500hp anymore

 

As far as a 60-1 making 200hp less than a 62-1... that's more like under optimum conditions the 60-1 will make 200hp less at the wheels than the 62-1 will BHP (at the crank)

 

Yes, I understand... trying to find out more info / specs / maps on the said turbo... Will post when I get data...

 

i have a 60-1 on my v6 car almost 400 rwhp and a boatload more tq

 

Exactly. Two twins with an equiv area to a single with 57mm were replaced with a twins having an equiv area of 76mm. That put the lb/min in the center of the efficiency region (75%) at peak boost, but causes a problem at 5psi. Where as, the smaller turbos would spool quick but at the end of the map in the inefficient area (60%).
The vehicle went faster with the bigger turbos due to the gain is intake and exhaust flow.

EDIT: still running the TPI intake? What is the cam in it?

 

Something else to think about is the turbine. In my example with the compressor surge, it could be fixed with bigger turbines. That would fix the surge but make it spool slower.
It is a juggling act to get it just right with the most effieciency.
The sqirrelpf site would help pick a compressor if you know the cam specs. Garrett does publish turbine maps that you can sort of match up to other turbos.

 

XFI260 Cam.... Duration @ .05 210 in 218 out... not much overlap...
Yes, TPI....
So maybe 400 with 15 lbs of boost on 305???

Again, trying to get data from Garret, and Ed (BBS), etc...

 

Yeah 530's with my 6766.. for reference my old ebay turbo was 60mm (called a T70) and never got out of the low 400's rwhp. I also stuck that t70 back on the new headers as a test and it was pretty slow. Right now I think I've reached the limit of my setup with the 67mm and will be trying something in the 76mm range.

 

That's where some confusion is...
Ed said 60, I'm assuming that is compressor wheel... but as you said, you had a t70 with a 60 wheel.... I did email him...
400 on the 305 with more torque would be great...

 

the ebay turbos are retarded , the ones they call t70's u can get with a 57,60,or a 69mm wheel

ebay turbos can not be trusted by the size they list them at i.e t61/t70 t88 etc

read the add and most of them will list the actual wheel sizes

 

BBS was selling Master Power turbos. When he says a T70 he means a 70mm wheel. The only turbos that I know of labeled a "T70" but really are 60mm is done with the china/ebay turbos. It is the ebay false advertising that is causing the confusion.

Keep in mind the a lot of the engines being discussed here are 350 / 5.7 liter.

 

He mean 60-1 or t3/t4 super 60? Physically there isnt any difference in a t60 or t70 from master power

 

I happen to have a master power t70 in need of rebuild or center section if you might be interested.... would take 100 buckaroos for it.

 

Reply from Ed...

Clarifying a few things;
I am pretty sure TurboedTPI's turbo is a 60-1 turbo, that turbocharger has a .70 A/R compressor housing. The turbo manifold I send you can only use a .60 A/R compressor housing. The main difference between the 60-1 turbocharger and the 60 trim turbocharger is the compressor wheel exducer diameter, turbos with a .70 A/R compressor housing pack compressor wheels with larger exducer diameters. The exducer of a compressor wheel is the back portion of the wheel where the compressed air last has contact with the wheel itself as it exits the wheel's blades.
For the 305 I would choose something a bit smaller than a .96 A/R turbine housing, perhaps a .81.
As for quality turbos, go for the real McCoy. Do not buy cheap wastegates either, they will get stuck and will cause overboost problems with possible serious damage.
500rwp is very doable, but you will need a stand alone or something that will enable you get timing and fuel control. Go for a good set of injector with the correct size, dont go for something exgerated in size or idle problems could occur. Do not go with "just barely the necessary".
Fuel pump is a must also. In order for me to use the fuel pump of my chosing, I left the in-tank fuel pump untouched, but ran a separate mini tank which is fed constantly with gas by the tank's pump. A huge fuel pump gets fuel from that mini tank towards the rails and excess is then injected back to the minitank. The minitank excess fuel is exited from the top to the factory tank. This method also always keeps fuel in my injectors even in tight turns and low fuel level conditions.

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I did see a single older 60mm turbo on a 5.7 tpi @ 9 lbs. of boost making 350 hp 450 tq.... So while I don't think 570 hp will happen with it, it seems like a good amount of power can be had on the 305 or 350 while keeping AC!

Rafael