67Firebird455

iTrader: (27)

Whoops, thinking too fast, not typing fast enough! LOL That's exactly what I meant to say, someone was saying that LSA has no effect on overlap. Better change that before I get flamed.

engineermike

You can't compare low-end torque between 2 turbo cars because it has too much to do with the way the dyno run was started. You see where the ZO6 dyno run was started at 2200 versus the GTO at 3200? That gives the ZO6 turbo a chance to spool up much sooner and make more low-end. Also, the GTO shut off his dyno run early because of lean A/F ratio, so you can't look at the 5500 rpm cutoff either.

The T76GTS turbo on the GTO is generally considered to be too small for engines over 330 cid, so it will limit the rpm range and not make quite the hp of a larger turbo. When you try and compare a ZO6 with a GT4088 to a GTO with a T76GTS, you can't assume any differences in power are due to the camshaft.

brad8266

iTrader: (23)

Then why are you posting about the effects of cams on turbo engines in the first place? You tried to show a great example of a turbo car with big cam now you are saying power differences are not from the cam but the turbo? Im confused. That cam combined with that turbo is the reason the GTO has a shitty powerband, it doesnt make good power down low and it drops off way early. What is the point of having a 1500 RPM window of power that is only in the mid range? Thats not even very track usable and it isnt very street friendly either.

man my typing sucks today.

engineermike

My point was. . . to ALL that think the Torquer cam is not a good turbo cam, check out the GTO's dyno results. Considering that it was in a car with an non-optimal turbo at a very low boost level, it made excellent power. Is that so hard to understand?

Go back and read my earlier post. It doesn't have a "shitty powerband". I hate repeating myself.

You'd freak out if you saw some of my dyno runs. 5500 - 6200 is all. It's cool, though, because I run 9's at 146 mph at 3750 lb.

Mike

Pro Stock John

iTrader: (34)

5-6 psi on a 04 GTO block hitting 650rwhp with that cam is a bit hard to believe, I would think that car was hitting more boost than that. I would believe it if it was an LS2 engine.... oh well I'm not hating or anything.

Reality though is the stronger the car is NA, the less boost you will see. Eventually the engine is so strong that it's pointless to add FI because you are doing a ton of work to squeak out a bit more power....

eb02z06

iTrader: (18)

I agree with engineermike, big cam will make big power-it's as simple as that. Just go for it. A little bit of overlap never hurt anybody-IMHO it actually helps a street car live with boost and pump gas.

brad8266

iTrader: (23)

Well the torquer with the turbo did make big power in a 1500 band that was all midrange. To me that not very good. I am sure it gets down the track fast and all but it could have been done a lot better.

brad8266

iTrader: (23)

i agree with that too, but that big power only lasted 1500 rpm's and in the midrange at that. Not optimized for the street and not optimized for the track.

LSONE

iTrader: (1)

I currently run the torquer cam, and I'll be installing my turbo kit as soon as I piece everything together. Later, I plan on switching cams to something generally considered more turbo friendly. You guys will have a definitive answer then (unless someone beats me to the punch).

As for this argument, you guys are comparing apples to oranges. They are running completely different setups, the Z06 has much higher flowing heads and an LS6 cam over a stock LS1. The GTO has aftermarket heads and a large cam, smaller turbo, different drive train, etc. It doesn't even look like the GTO had it's tune down 100% This banter is quite pointess.

engineermike

For chrissake, would you quit repeating that non-sense. The turbo didn't spool until 4100 because they started the dyno pull 1000 rpm higher than the vette, then they shut it off at 5500 because it was going lean. If they had made the pull from 2200 to 6300 like they did the ZO6, the GTO would have out done it all the way. That, I gaurantee you. Crap, even ProStockJohn, a highly knowledgable and respected board member, is saying that the GTO's power numbers were so good they are hard to believe. PSJ and myself both have 9 second turbo cars and are extremely impressed, if not in disbelief, of the GTO's numbers, but you still insist it's extemely inefficient!

Mike

brad8266

iTrader: (23)

Oh well my bad then I didnt know they shut it down due to lean issues. hey whatever man that is the baddest GTO ever built. Feel better now?

Got Me SOM

iTrader: (2)

somebody needs to just sit down and test cams on a turbo engine to see what the hell really works.

eLTwerker

Hey mike-sent you a pm, did you get it?

engineermike

I agree 100%!

I almost got a chance last year when I built the T76GTS blow-through carb'd 377, but we ran out of time due to customer constraints. All we dyno'd with was a 230/230-114 HR.

engineermike

I got it. Take a look at this website. If you have any questions when you get done, shoot them at me.

http://www.forcedinductions.com/help.htm

http://www.forcedinductions.com/helpadvanced.htm

perdieu

iTrader: (1)

well seeings how my set up is being used as a reference let me post up some more info

the first dip in the graph is where the meth comes in at the next dips are where KR kicked in.. 4* because this is my first boosted car I didn't know I needed to re-work the PCV set up.. I've corrected that and will be hitting the dyno on Monday to do some more WOT tuning...

Oh the reason it "only" goes to 5600 was the A/F was not where I wanted and we let out of it..

I'd sure hate to see what it would do if it was set up right and I knew what I was doing..

Got Me SOM

iTrader: (2)

I wonder if you Mike (since you seem to be very knowledgeable and intelligent) on behalf of ls1tech can make a proposal to Comp Cams and have a mule turbo engine on an engine dyno and just test out all the different grinds so we can once and for all clear up the mystery of turbo cams.

There shouldn't be such a damn mystery to this!

engineermike

Thanks for the kind remarks.

I actually have access to an engine dyno for cheap/free and also a chassis dyno for cheap/free since I'm friends with the owners of Wall-2-Wall Engines and Thunder Racing. They'd both be interested and stand to learn something from this test also. Since Geoff (Thunder) does alot of R&D with Comp (and business as well), he could probably pull some strings and get 4 or 5 cams to try. I could set up a test plan to learn the most from the least amount of tries.

The only thing we're really lacking is a test engine and turbo setup. Heck, I'd pull mine outta' my car if the ECM, gauges, ignition, versafueler, and Methanol wiring wasn't so involved. I'd test it on the chassis dyno, except that the auto/loose converter skews the numbers so much, not to mention that LT1 cam swaps are a real PITA. Ideas?

Mike

Got Me SOM

iTrader: (2)

I'm sure one of our members on this site would volunteer their motor if they had a little incentive like to keep the cam that works the best or something. Its an idea.

Maybe a sponsor would volunteer lsx engine with a turbo it if we're really lucky. Everyone would stand to benefit from the testing and we could push the envelope on these late model smallblocks even farther!

67Firebird455

iTrader: (27)

I know I would definitely be interested in the outcome. Keep us posted if you can work something like that out Mike!