I'm seeing about 14.5lbs at 6300 with my 8"/3.33" pullies. Should I go to the next size smaller s/c pulley(3.15?) to help my boost come on sooner down low? What would put me around 16lbs? I am down a decent amount of power(compared to my powerdyne combo), until about 4900rpm where the YS takes off. Thanks.
1988 5spd Coupe
Powerdyne combo-427rwhp/415rwtq 12.2@120--2.0 60ft.
YS combo-525hp/455tq
how much are you down?? When we chatted before I have mailed and chatted with several with our combo and the stocker pulley setup seams to do a standard 18psi on our combo's. I think the 3.15 with raise you between 1/1.5lbs of boost to just around 16ish:)
At 2800 it's down about 30hp and 55tq. At 3800 it's down 40hp and 60tq. At 4400 it's down 35hp and 45tq. Don't get me wrong. It makes 100 more peak hp and about 40 more tq. I'm just wondering if a smaller pulley will help my power a little lower in the powerband. At what rpm do the stock pullies(8"&3") make 18 psi? thanks.
1988 5spd Coupe
Powerdyne combo-427rwhp/415rwtq 12.2@120--2.0 60ft.
YS combo-525hp/455tq
at 6000rpm...so when does your combo break even on the dyno?
Around 4900rpm.Originally posted by -ice-man-
at 6000rpm...so when does your combo break even on the dyno?
Ever thought of winding it out to 6400/6500 motor rpm just to help with the other pulley to; to get the YS in its range? I am thinking of doing that and I know I have the airflow etc for it just not sure on the stocker rods and bolts anyone have some input on 6400rpm gear shifts?
I don't know. That might be pushing it a little bit. I'm sure it will keep on pulling though. I'm thinking the smaller s/c pulley will definitely help it "spool up" faster.Originally posted by -ice-man-
Ever thought of winding it out to 6400/6500 motor rpm just to help with the other pulley to; to get the YS in its range? I am thinking of doing that and I know I have the airflow etc for it just not sure on the stocker rods and bolts anyone have some input on 6400rpm gear shifts?
I would say the stock rods, bolts, and block are not too far from their limits @ 16psi. I had a 331ci combo with manley rods, ross pistons, and a steel crank with a main stud girdle, on a stock block. It was fine for about 12 passes and the block just fell apart luckily I tore the motor down before anything major happened. It had a vibration in the bottom end and I new something was wrong. I purchased the car with this motor, I did not put the bottom together, and I already anticipated a built A4 block soon. I had a T trim with 18psi on the guage tuned with WMS SDS.Originally posted by -ice-man-
Ever thought of winding it out to 6400/6500 motor rpm just to help with the other pulley to; to get the YS in its range? I am thinking of doing that and I know I have the airflow etc for it just not sure on the stocker rods and bolts anyone have some input on 6400rpm gear shifts?
When I unbolted the main stud girdle all the mains just fell apart, that was the only thing that kept the whole motor from going. Luckily all the internals were unharmed
I have seen guys even friends of mine run stock internal and block up around 6500-6700 rpm. The blocks does give up the ghost, it is just a matter of when. The stock block will only last so long turning those type of rpms. Remember the rule of thumb: RPM KILLS MOTORS..
Now on the flip side of the coin, I split my stock block right down the middle and I never turned over 5500 rpm with my Kenne Bell. Mine was a load problem in the drive train, I believe.
393 stroker with YS-trim Vortech :-)
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