Figured I'd make this its own post since a lot of people have been very curious to find out the results of this.
Well the results are in...
Cut-out Closed: 160whp 137wtq
Cut-out Open: 169whp 151wtq
9whp 14wtq increase with the Cut-out open.
Disclaimer: The first run was with the Cut-out closed, I think the car might not of been at full operating temp yet, so I might not of been getting full timing advance. But regardless it makes power, end of story.
I should also add the AFR was 12:1 during the closed run (no results with it open cause the dyno guy forgot to move the sniffer), so that being said....it should have a few more ponies to give up once I dial the fuel in.
I'll post the dyno sheet tomorrow from work, since they have a scanner there.
Here are the videos:
Closed:
Open:
Hopefully this will end the debate forever and hopefully put an end to the "you need back pressure, that cut-out is making you lose power" or "your losing torque with that cut-out"
Thanks for looking
yep... definitely convinced now. pauls car gained power with ditching the exhaust... and so did your's.
good freaking call, man!
but 169whp?!?!!?!? thats it?!!?!? somethings gotta be up...
Anything worth doing is worth over doing.
12:1 AFR I'm sure played a part in it.
I'm very happy with 169whp to be honest, considering its just a bolt-on/cammed Eco (Also minus balance shafts). Last year it only put down 145whp with everyone minus the balance shaft delete and the cams.
So 25whp from cams and balance shaft delete isn't to bad at all, for a 4cyl.
The dyno there I also think reads low (or just not inflated like some dynos), everyone always seems to dyno a bit less than expecting.
As an example, my buddy has the exact same mods as me, minus the ported TB, balance shaft delete and he only has the Stage 1 cams, he put down 152whp with a similar AFR.
wait.. what? i thought you put high compression pistons in it to??? guess not.
Anything worth doing is worth over doing.
id definitely be happy with that increase as well!
what are you revving to?
z yaaaa wrote:wait.. what? i thought you put high compression pistons in it to??? guess not.
Nope, I bailed on the full engine build.
Mods are in Reg, but to highlight power mods:
LE5 Intake Manifold
Bored TB
WAI
Comp Stage 2 N/A Grind Cams
4-1 Header w. Cut-out
Balance Shaft Delete
Stock bottom end, stock head....The head has never even been separated from the motor! lol
Smoosh - I'm reving it to 7000rpm
newt am looking at possibly doing cams. am pretty sure you tuned your car with your cams/le5, but what did the tuning consist of? would i be foolish to do stage 1 or should i suck it up and do stage 2??
also, where did you get your cams and what $ did you pay if you dont mind me asking.
Spalattero - I did tune it myself yes, other than the obvious (VE Tuning) I bumped the idle to 1000rpm and adding some timing at idle.
Idles great, some decent loping, never stalled at idle, never stalled during clutch in decel.
Stage 1 vs 2 is your choice really, 2 is obviously more aggressive so it yeilds more power, they run great under normal driving tho.
Only thing is, the Stage 2 don't wake up till 4000rpm.
I got the cams from Karo @ AllEcotec.com.
Do u have a electronice or manual??? I want a cut out but everyone says the electronic ones break alot
13.1 @ 115
awesome!!! now vids of this thing rippin down the track plz!
Nice gains! Those are not bad #'s at all, I'm curious to see what you can put down at the track now!
Member of J-body of Michigan.
For Sale
Congrats man, I knew there was a power increase with it open with my car, I wasn't imagining it lol. Nice numbers.
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
DJ Mike - I had just a plate on it last year, this year im running a QTP electric plate...we will see how long it lasts.
I went 14.4 last year with 145whp.
This year the car weights about 100lbs less and has 25whp more. Thats peak HP tho, the increase in area under the graph is massive. The gains at 7000rpm over last year are around 40whp and 40wtq.
That being said I'm very confident this will run into the 13's, we will see on June 6th.
Also, here is the dyno sheet, I had to write the RPM in myself as the idiot had HP and TQ over MPH.
id suggest doing valve springs, you may be having a little float issues with the cams and the high rpms which could also be resulting in a lower whp though, just a thought, otherwise @!#$ awesome
LE61T PTE6262 Powered
Well I thought I noticed a difference with my Butt dyno, nice to know that there is a for sure gain. I didn't think it would be that much though.
Wow look at the broad flat torque!! I thought stage 2 would be more peaky than that, but that graph is sweet! I mean, you're right about them waking up at 4krpm, but after that it's bliss! Looks like 7500 would be a good shift point.
QBE - I have the Supertech 78lb valve spring/retainer kit, I just listed the "power" mods above, full mod list in profile.
i drive a silver car - I to was surprised how much of a differance it made, I was really shocked how much extra torque it made.
oldskool - Im very happy how the graph looks, everything is nice and flat and smooth. Not really what I was expecting out of these cams but very pleased with the results.
Like I said earlier, the increase in the area under the graph is massive compared to last year. In some places im up 50whp and 40wtq, which is a massive improvement. I'm very excited to get this thing on a track now.
I have been considering reving to 7500rpm, Im curently limited to 7000rpm since thats as high as my tach goes. As it stands I drop back into most gears around 4200-4500rpm, but as you can see by the graph, 4800-5000rpm would be the sweet spot, and a 7500rpm redline would get me there.
The other nice feature is 7500rpm in 3rd gear is good for 100.6mph, so I might still be able to get away from having to shift into 4th. Saves me about a tenth I bet
Thanks for the comments guys!
damn... i need cams and a balance shaft delete lol i'm really surprised buy the graph i was expecting a drop at low rpm because of the open header.
ʇı ɹǝʍo7 | ǝcoMonstǝrs
Fluffy - you can see a slight loss in power with it up under 2500rpm...lol not that that low of RPM even matters...haha
Just did a quick check of last years dyno (before the cams and balance shaft delete)
Last year @ 7000rpm the car made
~110whp & 85wtq
This year @ 7000rpm the car made
~165whp & 120wtq
55whp and 35wtq gain,thats like a 40% increase in total power @ 7000rpm.....June 6th couldn't get here soon enough!!
@!#$ I love this motor
Finally some hard data to kill the damn back pressure myth. Props to you and well done. I was just going to order a QTP electric cutout too...
Paying someone to install parts and bragging about it being fast, is like watching someone bang your wife and being proud to raise their kids.
im not sure with the whole backpressure thing myself. my 03 cavi stock ran 15.7s after a clogged cat i busted the guts out and have ran it at the track with the exhuast seperated after the cat and it ran 16 flats. about a week ago i got it welded back together and back down to the 15.7s. so i would stock you need the backpressure as to my personal experiance. dont kno about modded cars tho as mines stock
And even with absolute proof smack in their faces, they still force the myth to live on....
Paying someone to install parts and bragging about it being fast, is like watching someone bang your wife and being proud to raise their kids.
awesome times, now do what I failed to a few years ago!
then, port the head and put stage 3s in there. you'll be over 200 at the wheel I'm willing to bet and even faster.
jeas pj... with a cutout you woulda ran 13's.
Anything worth doing is worth over doing.
