S/C or H/C/I?

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One of the mags did an article on this subject several years ago. HCI vs. a 5-6 pound blower. The gist of it was that either one nets you about the same gains, but the combination of the two is more than either one together. Engine + HCI = 2. Engine + blower = 2. But 2 + 2 = 5.

Even though this sounds kinda dumb (2+2=5), there's actually some merit. The reason why is because blowers multiply n/a power. So when you add a HCI and then a blower, you actually benefit from the HCI again when gained from the H/C/I is multiplied too when the blower goes on.

For example, a stock 5.0 makes around 190 rwhp. With a top notch H/C/I and supporting bolt-ons, you'll push between 300rwhp and 330rwhp. With a really efficient supercharger at 10psi on top of the same stock 5.0, you'll make something like, 190*(1+10/14.7)=319rwhp. Usually blowers aren't quite that efficient, but you should be pushing an honest 300rwhp. So, either choice will get you in the neighborhood of 300rwhp, and will pick up about 110-130 rwhp.

When you add a blower on the motor that already has a H/C/I combo, the math changes a bit. Now the motor's already making 300rwhp and the math looks like this: 300*(1+10/14.7)=504rwhp. A gain of 314rwhp over stock. Again, it's not going to quite work out due to inefficiency, but you're still picking up much more with the blower & H/C/I combination than would expect if you just added together the power gains you'd pick up from either one.
 
:lol:

I guess I'll chime in on this since I've gone the route so many in here are theorizing about.

I installed your typical full exhaust, cobra intake etc etc. A ton of boltons. Car was quick and quite fun. To me, and every car I was whooping on it was quick. Your typical engine swap civics, other v-8's and an occasional sti or evo.

Then I added the vortech with 6 lbs. I dynoed at 294 rwhp on a dynojet. To those who say you won't be impressed :thinking: I strongly disagree. It was impressive and fun. It's about a lot more than just a dyno digit. It's when your power is available and your torque curves. The only car I lost to was a midrange modified supra. I beat many lsx's and other stangs W/ hci. This constantly pissed em off since we were at similar power levels.

I then went to 10 lbs with the 6 rib setup and was seeing around 320 rwhp on a dynojet. I was disappointed and bought twisted wedges, ed Curtis cam. Then I dynoed at 368 rwhp on a dynojet and all this WITH A CRUMMY TUNER.

My next move was an 8 rib pulley kit from vortech with an underdrive built in on the crank and 12-13 psi boost. On a mustang dyno and with one of the best 5.0 tuners in the US, I am putting down 420/410.

So there you have it. Expect similar numbers with each combo.

My advice: you're used to boost, boost it. Who gives a flying ***k which you choose to do first if you are considering doing both. There are plenty of kits new and used that are amazingly affordable. :nice:
 
:lol:

I guess I'll chime in on this since I've gone the route so many in here are theorizing about.

I do like to theorize. I've also got a little experience. ;)

for me, 420rwhp at 10psi, with the stock cam, GT40X heads, and a non-ported GT40 intake.

Here's a 260rwhp H/C/I combo n/a that w/ 10 psi boost from an efficient blower made 390rwhp: http://forums.corral.net/forums/showthread.php?t=1280026

Modo over on corral with afr165, b-31, gt40, s-trim @ 14 lbs made 560 and went 11.12 @ 126 on his stock 93 shortblock. That puts him in the high 400s at 10 psi - maybe 460-470.

Five Liter Fox made 520 rwhp at 13 psi with box stock Trick Flows, & RPM intake with an E-cam on a stock rebuild bottom end 306.

stangin' went 462rwhp @ 9psi with a ported cobra intake, afr 165, fti custom cam, novi 1k.

I'd say those are pretty consistent results with my theories.

Cheers!

Chris
 
:lol:

I guess I'll chime in on this since I've gone the route so many in here are theorizing about.

I installed your typical full exhaust, cobra intake etc etc. A ton of boltons. Car was quick and quite fun. To me, and every car I was whooping on it was quick. Your typical engine swap civics, other v-8's and an occasional sti or evo.

Then I added the vortech with 6 lbs. I dynoed at 294 rwhp on a dynojet. To those who say you won't be impressed :thinking: I strongly disagree. It was impressive and fun. It's about a lot more than just a dyno digit. It's when your power is available and your torque curves. The only car I lost to was a midrange modified supra. I beat many lsx's and other stangs W/ hci. This constantly pissed em off since we were at similar power levels.

I then went to 10 lbs with the 6 rib setup and was seeing around 320 rwhp on a dynojet. I was disappointed and bought twisted wedges, ed Curtis cam. Then I dynoed at 368 rwhp on a dynojet and all this WITH A CRUMMY TUNER.

My next move was an 8 rib pulley kit from vortech with an underdrive built in on the crank and 12-13 psi boost. On a mustang dyno and with one of the best 5.0 tuners in the US, I am putting down 420/410.

So there you have it. Expect similar numbers with each combo.

My advice: you're used to boost, boost it. Who gives a flying ***k which you choose to do first if you are considering doing both. There are plenty of kits new and used that are amazingly affordable. :nice:




:nice:
 
Those seem like consistent numbers fast. The dyno I last dynoed at 420 is constantly 11% on the nose less than other dynojet dynos in the area which puts me right there. I have box stock everything except I home ported the lower cobra.

As for the comment about theorizing, it wasn't a blanket statement or I would have said all :nice:
 
Never hurts! Kind of what I was doing, along with some of my kills. I have more than I care to list here, but wanted to bring some of my real world experience. :nice:

Now if I could get rid of this crummy non efficient blower...:(
 
Good feedback guys but I'm still at a loss. I guess my question is if I do HCI then bolt on a S/C how long will the block last at 450-500 whp? If I do the S/C first I can run the piss out of it and then once she goes do the entire motor and do it right. The car is basically gonna be just a weekend toy to play with so downtime isn't a huge issue.

I should be able to tool around on 6-8 psi for a while in a stock motor? Obviously if I really wanted too I could go cheap and get a explorer top end with a b cam but I'd really like to put a quality motor together down the road anyway. This is hard, I always hate wasting money.
 
Well I pretty much answered most of that info in my posts. I purchased the car with 74k miles on it in late '02. I put the sc on it in 03. Ran it with 6 lbs and then 10 lbs for 5 years, and have been running it with the heads and cam for 4 years, and had 13 lbs for a little over a year. I keep upping the boost and all is well. Now I have 99k on it and I would say at least 20k has been boosted. :nice:

Hope that helps.
 
Well the motor is a 88 speed density motor which i plan on converting to MAF. Owner said it has 90k on it but its a crap shoot as to how strong the motor actully is. All my boosted vehicles have been wrx's and lightnings that were made to be boosted from the factory. The 88 had forged pistons correct?