Xtreme 403 Results
 

I went and got my car tuned at Xtreme Horsepowere in North Richland Hills on Friday. It put down 463 rwhp and 462 rwtq. I have stock induction which killed me on the big end the car stopped making power at 5800rpm. Time to invest in a Fast 90/90 or the new Weiland and I need a bigger MAF.
My car has a Texas Giant, PRC 5.3L, and full bolt ons. I would like to say thanks to Xtreme Horsepower for coming through with a great product (403 shortblock) and their Xtreme customer service. It is the best shop I have been to in the DFW. Thanks to Arvil and all the crew over there. :nod:

Looks solid. Can't wait to see what she does with a ported 90/90 setup and don't forget to upgrade to a bigger MAF.

Nice numbers, I think you are right...there is an intake restriction keeping it from pulling past 6000. What cam specs (TX Giant) are you running?

Its a 248/254 611 613 112+1. Car made AWESOME low end TQ and HP. I havent gotten the dyno sheets scanned yet, but it was 400RWTQ at 3000rpm. The intake and TB and maf are really holding it back. We are debating on getting the 90/90 or waiting on the Weiand to come out and see the results with it. Maf we were looking at the 85mm lid and maf combo or the new 100mm.

Ok D now it time to make some passes!:D

Yea intake is definately holding you back, in fact with a fast 90/90 you could probably see over 40hp if you get it "massaged" and keep that low end grunt. Solid numbers though considering, Congrats.

What made you go with those heads for your 403?
I have those same heads with a ported fast 90/90,but I'm still at 346ci with a tr224cam. I wan to go to 400+ci,but did not know if these heads would be a good candidate( I dont wan to buy another set of heads).I guess now when its time to do the bottom I'll just buy a 408 from TSP and reuse my heads.Did you have these heads on a 346 at one point,and were in my same situation? Any input would be great,as Ive thought about this set up for some time
thanks
john

5.3 heads wont hold you back that much. they are very similiar to LS6 heads when ported. He needs an intake to that flows... the heads are not the problem. :google:

I would've thought the HP would be higher but as mentioned I bet you would be pushing 500RWHP with a 90/90 setup. That torque is awesome!

Who knows about what it would actually put down. Unless Arvell and crew at Extreme HP have re-calibrated thier dyno..... it has been known to be inconsistant with other dynos in DFW. Regardless.... it is likely a stout combo!

I had the 5.3L heads on my H/C stock motor and I went to RPM in Lewisville and got it tuned and it blew up on my way home. I did the same thing with this motor and it made it the round trip. I used my same heads cause just like you said I didn't have the cahnge to turn around and buy some more heads. I am happy with the results this time around. I know my induction is still stock and is my limiting factor. Only gotta spend another couple of thousands.............

If you are going to dis anybody in my thread it shoud be RPM.

ha ha we cant go anywhere with out getting into some shit!!:engarde:

Indeed it is a stout combination with ALOT left in it. Theres certain other shops in DFW that I wouldnt even trust to dyno my car anymore. :punch:

Hey man,
thanks alot for the info. I have a ported fast 90/90,so instead of doing a 383 I'm just step it up to a 402 or 408. To the o/p sorry I did not mean to hijack your thread