ZohSlow

Heads/cam? My goal with my 07z is to make 600rwhp N/A with no bottle and still be my daily driver! Any suggestions?

Katech_Zach

Lets rule out the chassis dyno variable. How much are you looking to make at the crank?

RC45

Without access to the engine dyno though, how would someone verify their build results as being anything close the "desired crank numbers"?

So in light of no access to an engine dyno, wouldn the topic starters question seem correct to address rear wheel horsepower first. As thats easily (yes its "inaccurate") measured to observe changes.

A before / after set of runs on the same dyno should still be more accurate than a "guess" at what the crank hp would/should be for a setup that is never going to be dissassembled and placed on an engine dyno.

That being said - my uneducated laymans guess is that to go from about 460rwhp to 600rwhp on the same chassis dyno, the car would need a Halltech-style free flow intake, 90mm+ MAF, ported LS7 intake, ported heads and pretty hefty cam and exhale via some long tube headers and a full 3" exhaust system with free flowing mufflers.



BTW, is it possible to get 700+ crank HP from a pump gas N/A 427?

Z064U2NV

About 1000 of these should do the trick.

Katech_Zach

There is a reason for my question. Everybody is fixated on 600rwhp. I can only guess that it is because it is easier to tell people. When I'm out at a cruise night and somebody asks how much horsepower my car makes and I say 610 the next question out of their mouth is always "at the rear wheels?" Next, I want to know what you think it will take (horsepower at the crank) to make 600 to the wheels.

RC45

Everyone is "fixated" on rear wheel hp, because in the real world where we live, access to SAE certified engine dynos is just not going to happen - so for enthusiasts rear wheel (or front wheel) numbers are the only yardstick.

Albeit a slightly inaccurate yardstick, but its all we have.

So when yo usay "610hp" at a cruise night, unless you car is a "stock 610bhp car" of course people are going to ask "At the wheels?" - because thats the common yardstick.

I dont know abotu you, but I have been to cruise nights where people say "This car is a 750hp at the crank setup".

So I / we ask "Hhmmm 750 crank? What does it put down at the wheels?" And they say "Well I dont know I have not had it dynoed."

So the poor sap is going by some "crank HP" claim and may never know if the car delivers what he paid for.

At least a "before / after" set of pulls on a chassis dyno gives a measurable result and observable delta to determine if your money spent gave you any improvements.

And as to what crank HP could net approx 600rwhp? I am conservative, and would guestimate about 670bhp could net 600rwhp.

I have to ask, with all the resources Katech has available, why dont you guys do more engine dyno / chassis dyno comparison the same cars to show that a Katech 660 (as an example) would likely show 580 or 590 rwhp on your chassis dyno?

^^ I use the above as an example btw.

But either way, hp numbers schmoshpower numbers - if the car starts out fast and ends up faster, then mission accomplished

Katech_Zach

With chassis dynos varying 12-15% from shop to shop, this real world comparison is no good. Here is the problem: Your yardstick has the same numbers on it that mine does, but your yardstick is 8 inches longer. How is that scientific?

I do.



You're right. This is the only thing a chassis dyno is good for.

This makes it clearer to me why everybody wants 600rwhp. It would take well over 700bhp to make 600rwhp on our chassis dyno.


1. We do this all the time. Every Street Attack package gets dyno tested on the engine dyno and the chassis dyno.
2. There are too many things that change. The exhaust configuration on the dyno is different than what is in the car, the controller is different, there may also be other variables.

ZohSlow

Right now the car has Kooks 1 7/8 long tubes, offroad x, B&B bullets, tune and intake. Car made 489hp and 467tq on a dynojet. So the answer to my question is I need ported manifold/tb, ported heads, and a big cam? I want 600rwhp because my buddy has a 02 z06 and he put a 150 shot on it and hes beating me now! I can't let that happen

RC45

OK - this is exactly the can I wanted opened.



If every C6 Z06 LS7 is with x% of the SAE certified numebrs, and those numbers are 505bhp, then surely if a particular chasis dyno reliably and regularly reports the rear wheel dyno numbers of the C6 Z to be 440 to 450rwhp, is it not acceptable to then use THAT particular chassis dyno to help determine your crank HP from the measured rear wheel hp?

So if that C6 Z06 LS7 is 505 crank hp when it is 450rwhp, what would you estimate the crank hp of the same setup when it pust 600rwhp down on the same dyno in very imilar conditions?


Doesnt matter what changes, if the changes are constant.

What rear wheel numbers do your Street Attack cars post on DYnoJet dynos? (and I know they are all different etc etc)

That seems to be what it takes to get the 600rwhp number on a Dynojet yeah. As to what that is at the crank.. who knows, as long as you are fastre than your buddie right? hehe

Katech_Zach

If you have a baseline on the same dyno then yes. There will be variation day to day but lets throw that away.



672bhp

Take that number back to the original question. 672hp, 7.0L, 11.0:1, hydraulic roller, pump gas, daily driver - not possible. The highest horsepower hydraulic roller cam LS7 427 we have tested was 685hp and that had 14:1 compression, a very aggressive camshaft and a single plane manifold. To get to 702bhp out of a 427 it took a true race C5-R engine, solid roller aggressive cam and Katech C5-R carbon fiber individual runner intake manifold with shortened runners.



We've had reports of 550-560.

method

The answer to the OP's question (IMHO) would be the C6RS crate engine and then sell the LS7 to offset the costs.

I guess that's because horsepower at the crank sells cars.......
horsepower at the wheels wins races.

I'm still waiting for rear wheel dynos and 1/4 mile times/video for a 500ci C6RS.

The same info above for a Street Attack would be nice as well.

Frenchican

Just posting my results. Not sticking my beek in (well, maybe a little)

Katech Mustang Dyno = 515rwhp
A&A Dynojet Dyno = 536rwhp

Katech_Zach

C6RS information is up to Pratt & Miller to release.


For the Street Attack:
520rwhp on mine
11.3 @ 132mph w/2.0 60ft.

RC45

Well, I will agree that your "daily driver" comment is correct, but there are a couple of us with 600rwhp+ (Dynojet) pump gas hydraulic roller LS7's - and the cars are drivable on a daily basis, but not evryones idea of a "daily driver".

That goes back to my estimate that 600rwhp on a Dynojet is probably about 660 to 670hp and suggesting the poster be prepared for some serious tweaking to get 600rwhp (Dynojet) NA.

BTW, what numbers do stock LS7 motors put out on your Katech engine dyno? Close to the SAE 505 number?

Oh, and Jason, what's the price of your 500ci motor?

I dream of having 600rwtq NA in my car one of these days, and figure a super nast 500ci should be able to deliver that number.

Katech_Zach

LS7 engines with stock calibration, stock exhaust make 505-508bhp (J-1349 SAE).

Sending PM on the price for the 500.

Katech_Zach

Your PM box is full

RC45

Yeah - just emptied it

Thanks... as I was wondering if no-one loved me anymore. But it was just a full PM box.

bandit0220

Jason do you guys sell the C6R carbonfiber intakes??? just a ? and you never sent me the info on the 500 cu in engine that i requested and my box is empty hahaha

Katech_Zach

No, all parts on the LS7.R are intellectual property of GM.

Sending PM

BONDS

My car is at 580 rwhp on a nitrous tune! Tomorrow it will be at Dallas Peformance trying for 600+ at the wheels on a moter tune. I will post the results