jonesracing

just installed a super HX40 and PDR370s it runs good but not as good as I was hoping it would. It is boosting 45lbs. and boosts pretty quick but just feels alittle flat on top end. Could it be my stock timing holding it back on top end?? Thanks!

raychem

Yep..bump the timing to 18* anf torque down your head to at least 105 ft. lbs.

Richard

Cummins Freak

also be careful about barking that 40 thay are known for weaker shafts

TxDiesel007

What they both said..

stock timing is a kick in the butt in the lower end, but without the timing, u really cant enjoy the truck past 2200 rpms.. Try 16.5 or so just to be safe with the headgasket... and the HX 40's are not as strong as the 35's...

Rick

raychem

I'll tell you its all in how you drive, my 97 with an hx-40 when everybody was breaking tham lasted for 60k miles and NEVER gave me a problem running 20* plus degrees of timing and making 490 plus hp to the rear back in the early years before the C/R motors...lol.

Richard

Big Smoky

If you want some more power, go with laser cut delivery valves. I think you will really be happy. EGT's may get a little warmer, but I think you'll be happy. Talk to Big Nasty, he has the same set up as I'm talking about.

gunracer1

the super hx40 has a bigger shaft if i remember right. so it should be a much more durable turbo.

jonesracing

Thanks for all the replys . Laser cut DVs are next on the list. And Timing and a retorque. plus maybe back off on the pre boost fuel or adjust the transmission kick down.

raychem

Hold off on the DV's. You have a 97 which came with bigger delevery valves than the 95-95 trucks. The dv's in your truck are the 181's which have put down over 700 hp. Best spend your money on other things. Bigger dv's will add fuel that you will not burn since although you have a super 40, that pump is still capable of putting out more than that turbo can supply.