I think the low boost numbers are screwed. If you look at all of the low boost combinations, they are showing HP/psi near 30.

I believe this number is inflated. The reason being is that the stock motor will not ingest a full 1 atmosphere (ie 14.7 psi absolute) all by itself. A stock motor (or any motor with an obstucted intake path) will pull a vacuum on the intake rather than the pressure in the manifold being atmospheric. This reduction in manifold pressure greatly reduces HP.

With that being said low boost numbers are going to be inflated because the boost pressures that we are reading are for + atmospheric only. So a 3psi motor is actually:

3psi + amount of pressure to bring the manifold to atmospheric.

So we are actually talking about ~5psi because it takes about 2 psi just to bring the inlet manifold to atmospheric pressure.

If you redo the calculations including the additional psi it takes just to bring the inlet manifold up to atmospheric pressure then your HP/boost numbers drop back down to normal values.

JMO

 

Intresting theory, but thats why i take the AVG because it will drop the peak number down if its not consistent (Look at the AVG number for the T60 kit). I just want to keep the data real and not mess with it. If i started to adjust some results by 2psi or so, i will have to do it for all the kits too because it wont be fair for the other kits. U know what i mean?

 

PSJ was not happy with the YS Trim Avg. huh.. Looks like LSs1Power is using my 347ci motor for the P-1SC avg.. Cool..

Clint

 

I don't want you to change anything. I just wanted to provide an explanation for the the excessively high HP/boost #'s for the low psi setups, and so some people don't think that their kits suck.

 

The only problem I see with comparing these setups on a horsepower per psi basis is the FACT that some used pump gas alone and others used race gas, alchy, and other substances to make their setup more efficient.. I am sure Rob Raymer could take someone else's kit and add alchy and stuff and get great numbers as well. Rob Raymer knows forced induction.

 

the higher or stock compression motors are more efficient and on the same system (octane permitting) should always make more hp because their effective compression will always be higher for a given psi.


great list!

also curious, if you are interested in my turbotech street kit numbers or qmp kit numbers pm me.. dunno if they should count or not?

 

Sure, U got a PM.

 

I think u already did explain it in ur QUOTE "it takes about 2 psi just to bring the inlet manifold to atmospheric pressure." But doesnt this theory apply also for a car that is running 16psi? So bascially it is running 18psi instead of 16psi?

ALso I didnt make the list to make people think their kits sucks.... Im sorry if someone was offended. If u guys want me to take the list off, its ok by me.... I just thought it was a good refrence for us LS1érs.

 

Dude, your list is great. Don't take it the wrong way.

I just wanted to provide an explanation for the 30+ HP/boost numbers that were showing up.

I don't want to drag this great thread off track with another long winded thread, so I'll just keep my .02 for this one.

Your doing a good job, keep it up.

 

Thanks.

 

If nothing else, it will give people a lot to compare to. I'm sure I could have made more power had ls1edit been available when I was stock motored but dem dare is da way it goes

 

Ya Baby Ya.. Boost Baby Boost..

I do agree with NoGo with the low psi high RWHP per lb. Makes since to me. Looks like the Vortech G-trim numbers are lower than ATI.. Hey Blacknight you hear that??

Clint

 

LSs1Power. One more for the G-Trim Vortech.. My friend dynoed 547 RWHP with 11psi, on a 2000 SS with a stock motor. The motor would dyno about 335RWHP without the blower, with his Aluminum Flywheel, Carbon Fiber Drive Shaft, Mac Headers, Gutted Cats, LS6 Intake and K&N Air Filter.

547 - 335 = 212 / by 11 = 19.2 per psi.


Also Another one for ya..

My motor 99' SS Bone Stock with Billet Flywheel, Slp LT Headers, No Cats, LS1 Intake, LID w/ K&N Filter, MAF Ends & ASP UnderDrive Pulley Pulled 328 RWHP. I then added my ATI P-1SC-1 w/7lbs of boost. Dynoed 524RWHP.

524 - 328 = 196 / 7 = 28 per psi. Another high RWHP per PSI Calculation. But it's the truth.

Clint

 

I'm sure this was a lot of work but I just don't see how it proves anything. Almost all the cars posted have different specifications for the engines/gas uses besides just the form of forced induction.
The only way I could see it working is if every car was exactly the same with the exception of the form of FI. Then you could compare a psi to psi scale.
You also have to think even that isn't the best way to determine what car is going to be the fastest at the track since your basing the calculations on peak hp.
Great work though.

 

Unfortunely all your data does not in anyway show efficiency.

Gary

 

Im not basing my calculations on peak hp. Im basing my calculations on gain per psi which shows the efficiency of the system especially when u have alot of results posted from owners and u take an AVG of all of them no matter what engine setup they have or race gas or pump gas. U can see alot of 370-372CID and 346CID with stock C/R and low C/R motor gaining the same rwhp per psi. Im happy to say that there is huge consistency between results that are posted. Again its not about peak HP numbers.

 

What does show efficiency then?

 

LSs1Power..

I like your Thread here. It's good general info. Of course many people will say it really does not prove anything. I think it does. If you take many examples it does in fact show an avg per kit. Yes some cars may show more than others, however with many car being used in your list, the avg becomes more important..

Good work, and I know your taking your sweet time to post this info. Thanks again.

Clint

 

The above numbers absolutely show the efficiency of a FI setup.

All you need to know to determine the efficiency of a specific FI system are the RWHP before and the RWHP after and boost. Its just a matter of crunching the numbers.

Looking at the P1SC numbers that Hugger SS posted.

524 RWHP Supercharged
328 RWHP Naturally Asprirated
7 psi of boost

The efficiencies of the above system:
SYSTEM Volumetric Efficiency 119%
MOTOR Volumetric Efficiency 84%
INTERCOOLER Efficiency 81% (interpolated for standard atmospheric)
SYSTEM Flow Efficiency 87% (1.16 psi lost due to system eff.)


It's a good list. And shows some pretty significant things. Check out all of the systems without an intercooler

 

NoGo. Those numbers are for my friends Vortech G-trim SQ Blower with a 2.75" Blower Pulley, not the P-1SC-1..

Clint