506Hp/507TQ on only 9PSI???

[Red1990Lx]

Is is possible to make these kinds of numbers with H/C/I, 9PSI, low compression 306 and some other bolt ons? I am running all smog and some other less than optimal things but that seems kind of high. The reason why I think that it is high is because in the Mustang Monthly they had a write up on a 5.0 on 15PSI at 500HP.

 

[HGFireHazard]

Well, it seems a little over the top to me... but I can't help but thinking it's possible. I'm sure it would take a pretty radical H/C/I setup and every bolt on and a few other things. Any chance there came a dyno sheet with the numbers?

 

[Grn92LX]

Yes, it has been done many times with off the shelf basic h/c/i parts + boost.

Gmkiller on here is making 505rwhp with a stock cobra long block + custom cam + boost.

 

[HGFireHazard]

Yes, it has been done many times with off the shelf basic h/c/i parts + boost.

Gmkiller on here is making 505rwhp with a stock cobra long block + custom cam + boost.

There is no doubt that a person can reach 500 whp/tq with a H/C/I and boost, but the question is with 9 PSI of boost.

It seems to me that you add somewhere around 10 hp for every psi of boost, so with 9 PSI you add around 90 hp. While it's true that a really well matched and flowing combo might utilize boost better, that's a lot to manage.

Let's say a 306 has a killer H/C/I and that each PSI of boost adds 15 hp. At 9 PSI that would be 135 hp. If you subtract that from 500 you have a non-boosted NA combo that makes 365 whp/tq. That's a mighty combo on a 306.

 

[95CobraMike]

its close to possible

 

[xkuntrycowboyx]

yea, isn't the average on NA H/C/I combo's seen around 290 for us and some claimed up to 315-320 for a really well matched h/c/i ??
just something i think i remember seein

 

[cbarr300]

of course it is.....boost is just a measure of backpressure. If you have some kickass, high-flowing parts...then you WILL see less boost...but WILL flow more air....which WILL equal more power (even with less boost)

surprised?

haha

take for instance the 4 cyls running around pushing 22 psi. I remember one time when I told a guy how much boost I was running (10psi at the time). He laughed and said, "haha, that's weak, I'm running 23 on my eclipse." I asked him how much power he was making and it was somewhere in the 200 area...I looked at him and said I'm just over 400...with less boost than you. I asked him how that was possible...and he was kinda at a loss for words.

I guess he forgot I had 4 more cylinders than him ....and I can flow more air since I have those extra cylinders. Since I can flow more air..there's less backpressure...and since there's less backpressure...I'm showing less "boost"

now of course, I could do some ungodly combo and run 22 psi on the same engine in the example...but then I'd be wayyyyy above where I am now, lol.

Now, instead of having the 4 cyl vs. 8 cyl example....let's do v8 vs v8. One has some kickass parts and one has some parts that aren't quiet as kickass. Obviously, the kickass combo is gonna make more power....cuz it can flow more air and the other combo won't make quiet as much cuz it can't flow as much air. Now let's say we throw a vortech s-trim on each combo. Could it be that the kickass combo would show less boost...but more power? yup

so basically, I say all that to say....that with the right selection of parts.....

it most certainly is possible.

btw, I realize that there are certain what-if's to my example...such as cam selection. In actuality, the lesser flowing combo could make more power under boost than the good combo.....but that's a whole 'nother story.


sorry if I got some stuff wrong in my rambling...I'm a bit on the tired side haha.....seriously, my eyes are barely opened right now.

 

[SublimeRT]

cbarr has the right idea.

 

[gmkillr]

That could be done, but why only run 9lbs.? Im making 505rwhp on 14lbs. of boost, w/ stock heads, ported stock intake, and a Camshaft Innovations cam.
From my experience 1lb. of boost = 15-17rwhp
I now have my boost cranked up to over 20lbs. w/ an all new exhaust and should see well over 550rwhp, still w/ the same stock heads, stock ported intake, and C.I. cam, all on top of my 110,000 mile stock shortblock.
My car made 265rwhp stock, added the C.I. cam, and Vortech, and now see 505rwhp, so im seeling roughly 15-16hp per lb. of boost.

 

[millhouse]

I'm close to that now…even with a mismatched combo. My current turbo exhaust housings are far to small of a match for my cam…and as such my power/tq fizzles out slightly past 5300 rpm while my cam want's to keep pulling to 6k. I'm expecting with the larger .63 housings I'll be putting on this spring along with some type of ignition box 500+rwhp should be easily attainable at my current 8psi of boost.

http://videos.streetfire.net/video/3f193ee2-3089-440b-b132-99ea0150d4a0.htm

 

[ProKiller]

i'm with cbarr. also, you didn't say what kind of boost. turbos are more efficient. i'd imagine you could hit 600 with only 9psi.

 

[Badazgt.]

this topic was started relivent to my car...
Red90 Lx ill be happy to answer any of ur questions on here... i just dont get on CR anymore

 

[Badazgt.]

as im sure you know Boost is only a factor of backpressure... my setup on a stock motor might be worth 16psi or soo... I myself thought 9psi was low when we hooked the boost gauge up to my car during the dyno test... we used the boost numbers to watch belt slip... I've been told by 3 proffesionals that my GT-40P heads are the nicest ported cast iron heads they've seen.. i do not have the most expensive setup u'll find but i did make sure my combo worked great together... i had my intake port matched to my heads and insured i did the best research I could on my cam choice.. im overall very happy with my results...
dont get too hungup on psi readings

 

[Badazgt.]

millhouse nice numbers man... good to see u doing good also

 

[cbarr300]

exactly!

"boost" ranks up there with peak dyno numbers....It's nice to say you run "x" psi.

but there's more to the story than that.

yet another example for any new people on here or whatever:

Let's say you have two straws...one has a larger diameter than the other. Now blow through them...which one makes you run outta breath first?

the large straw obviously. Now let's say you were to hook a vacuum/boost gauge up to your mouth (just work with me ppl haha). Which one caused the most backpressure in your mouth? The small one obviously because you can't flow as much air through it. So now we have that the small straw causes more boost...and the large straw causes less boost, right?

buttt...we all know that the bigger one flowed more air.

sooo, boost numbers aint all they appear to be :wink:

 

[gcomfx.com]

exactly!

"boost" ranks up there with peak dyno numbers....It's nice to say you run "x" psi.

but there's more to the story than that.

yet another example for any new people on here or whatever:

Let's say you have two straws...one has a larger diameter than the other. Now blow through them...which one makes you run outta breath first?

the large straw obviously. Now let's say you were to hook a vacuum/boost gauge up to your mouth (just work with me ppl haha). Which one caused the most backpressure in your mouth? The small one obviously because you can't flow as much air through it. So now we have that the small straw causes more boost...and the large straw causes less boost, right?

buttt...we all know that the bigger one flowed more air.

sooo, boost numbers aint all they appear to be :wink:

I love analogies... and that was a good one.

 

[cbarr300]

haha, why thank you. I love using analogies as well. That's my favorite one to use to describe "boost" and what not.

I'm just waiting for Wes and Jt to come in and make a joke...

come on fellas...I know you want to haha

btw, you shoulda seen the first version I typed haha...they might have had to delete my post with some of the wording I chose haha.

 

[millhouse]

millhouse nice numbers man... good to see u doing good also

Thanks! Likewise!

 

[gcomfx.com]

haha, why thank you. I love using analogies as well. That's my favorite one to use to describe "boost" and what not.

I'm just waiting for Wes and Jt to come in and make a joke...

come on fellas...I know you want to haha

btw, you shoulda seen the first version I typed haha...they might have had to delete my post with some of the wording I chose haha.

I had a joke, but it was more along the lines "Wow, for a second I thought I was in the RIM job thread." But I tried not to get us off topic in every thread.

 

[Red1990Lx]

as im sure you know Boost is only a factor of backpressure... my setup on a stock motor might be worth 16psi or soo... I myself thought 9psi was low when we hooked the boost gauge up to my car during the dyno test... we used the boost numbers to watch belt slip... I've been told by 3 proffesionals that my GT-40P heads are the nicest ported cast iron heads they've seen.. i do not have the most expensive setup u'll find but i did make sure my combo worked great together... i had my intake port matched to my heads and insured i did the best research I could on my cam choice.. im overall very happy with my results...
dont get too hungup on psi readings

I hope there are no hard feelings.... I didn't try and call you out or anything over on CR, more along the lines of seeking information (what happened that you won't go there anymore). Our setups are about the same and I was just trying to see where the differences were at. To be honest with you, I have the smaller pulley on which is supposed to be good for 15lbs or so and I have yet to see where my boost guage falls at under WOT (little hard when all the car wants to do is spin). The tuner put a very safe tune on the car as this car was daily driven for a while but now it is just for pleasure really so I know there is more potential, I just don't want to push it too much more.