Wow, 50+ rwhp with the aftercooler. That is very impressive. Was this on a 383 and how much boost did you see?

I am going to run the 6.66 crank with the stock 3.33 pulley. My calcs show an impeller speed of 43,200 rpm (@6000 engine rpm). At this impeller speed and looking at the V2 compressor map, the pressure ratio appears to be in the vicinity of 1.9 (which is equivalent to 13 pounds of boost at sea level). Of course, with a bigger engine you may not see 13 pounds of boost due to the increase in the airflow requirement. Looks like this blower can support 1000 cfm (70 lbs/min) @ at 14.7 pounds of boost (a 2.0 pressure ratio) and it is still in a reasonable efficiency range.

 

I was seeing around 8 psi boost on a 383... I was seeing 9 before the aftercooler and 8 after I installed it and gained 54rwhp to be exact.

Come to think about it....

it dropped my temps from 190+ to 105F that is an 85 decrease in temps...

If I had the same total boost I would have gained more...

 

Highlander, I have almost the same combo as you just 210 afr and now 224 236 solid sq v2 vortec and aftercooler.
I had a custom 7.2 crank pulley with the 3.33 charger and I see 11-12 psi at 6300. Are many people spinning a s trim to 50000 or am I looking for trouble.

John Carpico

 

where did you get the 7.2???
also 50k is fine from what i have seen

 

There has been so many people spinning them that fast that its amazing... They dont granade like the older paxtons...

Nice units.. tend to last a lot!!!

ASPracing.com makes any pulley, any size.. you might want to check them out.

 

Nice numbers man.

Mike

 

I had a local machine shop make it for me paid like 150.00, I didn't want to use a smaller pulley on charger the smaller they are the more they slip.

John Carpico

 

Holly cow ... ... but I am wondering if all the details have been divulged ...

I had 11 psi of intercooled boost on a stock engine with headers and saw only 437 rwhp, and my A/F ratio was around 11.7:1 if I remember right.

Have a good one

LWM

 

The only way would be taht he has 300cfm+++ heads out of the stock castings lt1s

 

crazy numbers.. Congrats. Get some track times to compare to those dynbo numbers!

 

FYI, although they are definitely not 300cfm heads, the last guy with those heads made very close to 400rwhp N/A with an auto and a loose stall (stock bottom end, CC306, long tubes, 3600rpm stall) ... looks like the heads are making close to 100hp more with a similar setup plus a blower pushing 6psi. So, is a 100hp gain with 6 psi possible? That's slightly less than 17hp per psi of boost, which seems reasonable to me. Also, I *think* the poster has a 6-speed, which always helps the numbers.

 

To have 400rwhp N/A on a 350 it means he has one of the fastest stock headed and bottom end LT1 in this forum... or so...

Its not that easy... 280cfms will not give you 400hp to the wheels on a 350 unless you are spinning the engine WAY WAY HIGH... so those are some killer heads... or something else is missing.

 

Nah, I think it's probably more common place than you think. The only two 4th gen guys I wrenched with, george [austinws6] and jeff collop [jeffstar], were both extremely close to the 400rwhp mark with a cc306, long tubes, and heads (and a good tune, of course)... and that was several years ago.

 

Ok, so what is the RPM Range of a cc306 on a 350? Is it in the range of 6800+? That is way high to me. and when you mean close is what? over or under?

Still... with 6psi NON intercooled gaining 17RWHP / PSI is not that easy... and still a 6.66/3.33" pulley is just not enough to make enough airflow for 500rwhp...

And he said he was making 330 pre blower... which means he gained 170rwhp from just 6psi?????

I just want to learn where can I get more power that easy.

 

6800+? No point in spinning it that high, as it peaks around ~6200. 39x rwhp for both geo and jeff.