Pair 62mm Billet Turbos ?

[KWIKR 1]

after much research I'm thinking of a pair of Precision SC6265SP Billet Turbo's (T4 w/.81 AR) for my TT SBC project . what do you think to big to small , not big enough on the AR ?

Basic Combo as follows :

Wrenchrat Twin Turbo Kit ( www.wrenchrat.com)

4.125 bore (8.5 / 1 CR )

Eagle 5.7" Forged H Beam Rods with L19 ARP bolt upgrade

3.750" Eagle Forged Crank

Accufab 90mm TB

Converted EFI Victor Jr Intake w/ 95lb injectors

AFR 210 Alum Heads/Harland Sharp 1.6 roller rockers

Hyd Billet Roller Cam 238/232 @.050 (just over .600 lift/ 115 lsa )

Precision SC6265SP Billet Turbo NEW SC62 62mm T3 T4 on eBay.ca (item 350265101445 end time 10-Aug-10 12:15:31 EDT)

 

[rag231]

twin turbos

How much street driving are you planning to do or better street to race ratio. I had a pair of te-66 and upgraded to billet 67's and I have a pair of 70's on standby for my stage 2. I drive it everyday I can on the street and it is a monster on the track. I got the used on the racing mustang websites dirt cheap. They will put them on a car for a few runs and it's not fast enough then it's upgrade time. 2 billet 67's with 20 hard runs $1200

 

[KWIKR 1]

If I can find the time to get out to the track at least 3 times a year I would be happy . so..... in that case lets call it a primarily driven street car . I want something that is crazy stupid fun on the street and not a chore to cruise around in . and that I can drive to the track and lay a decent number down for fun . that's why IMO I kept the turbo sizing on the small side . from what I can figure out these turbos as a pair should be very capable of produceing a easy 700-800hp to the rears with what I have to support them . or actually any decent pair of 62mm turbos should do it as well . am I wrong in my thinking of sizing ?

 

[rag231]

62mm turbos

I had a ton of fun with 62's and I know for a fact that I didn't max them out. I only upgraded because I was at the right place at the right time. I only came out of pocket about $250 for the 67's and they are way more efficient turbo's for my combo ( a little less back pressure at the same psi). The spooling hasn't been time compared but I don't have a problem on the line. I have seen 62's go for $800 for the pair and you may or may not get the turbine housing that you need so ask around first.

 

[KWIKR 1]

I had a ton of fun with 62's and I know for a fact that I didn't max them out. I only upgraded because I was at the right place at the right time. I only came out of pocket about $250 for the 67's and they are way more efficient turbo's for my combo ( a little less back pressure at the same psi). The spooling hasn't been time compared but I don't have a problem on the line. I have seen 62's go for $800 for the pair and you may or may not get the turbine housing that you need so ask around first.

what stall were you using to spool the 62's ? any track time with them ? Thanks for the input it's very appreciated .

 

[Red C5]

IMO those turbos are too small for your application. They'll spool fast and make good low end power but will really choke up top.

 

[rag231]

turbos

With the 62's and .69a/r housings stall was 4000rpm and instant boost, 5.70's in the 1/8. ( learning curve years). 62's and .85a/r same stall , 5.60, billet 67's and alky 5.48 and still learning. I was told that I could have gotten there with a larger single such as a 47/88 but for some reason big singles cost more than used little twins. If I ever get to the point of maxing out this combo, maybe a pair of 70 or 72's would be next. But you can count on them not being the lastest and greatest and probably a year or two behind. I have to save my bucks just in case I want to switch to a v8 and go real, real fast.

 

[Dusty Bradford]

With the 62's and .69a/r housings stall was 4000rpm and instant boost, 5.70's in the 1/8. ( learning curve years). 62's and .85a/r same stall , 5.60, billet 67's and alky 5.48 and still learning. I was told that I could have gotten there with a larger single such as a 47/88 but for some reason big singles cost more than used little twins. If I ever get to the point of maxing out this combo, maybe a pair of 70 or 72's would be next. But you can count on them not being the lastest and greatest and probably a year or two behind. I have to save my bucks just in case I want to switch to a v8 and go real, real fast.

The billet 6765 is pretty awesome on the stage 2's. I put a set on a local car and ran several traction limited 5.41's and 2's but at 138mph. No doubt they are enough for 5.20's and 138 at 3400# if the track is good.