Ain't Skeered: You can use a adapter. The the low ram which I fully intend to get, is a Cathedral intake & I have Ls7 heads. That's about 1/2 inch added to those short as runners @ 3.45 inches So I figure 5.8 to 5.9 min. length needed to keep RPM in check.

 

Well, Smokey, I cannot find the dyno I was looking for. When I was on the phone with Tony (probably over a month ago at this point), he told me about the engine. It was very similar to mine, but 434 or 440 vs 428. I went looking for it, and I simply cannot find it. It was 70x rwhp though. While I was looking, I ran into some other threads with builds like mine, but a fair amount less cam, and they ranged from 650-670 HP. If I get that, I'll be stoked, as that would be 100 HP gained. One of them was a covfefe that ran 10.0@142 on DR

I think i'm going to need to bite the bullet on a couple of things. I'm running 26" QTP right now. Likely I will need 28's. I'll have to roll the fenders. I'm also looking to see if I'll need more fuel pump, but we will see. I'll try to run a mechanical gauge on the dyno and make sure I'm holding pressure.

After digging around more, I do agree with everyone saying the current cam is too small (obviously, since I have a new cam to fix THAT lol). Current cam is at 248/255 solid, that is ~242/250 hydraulic. Most of the LS7 builds out there start at 245/258 and go up from there. Occasionally, i'll find one at 240/252, and those are deliberately mild.

 

Sad...1 min search Darth.

https://www.corvetteforum.com/forums...er-tested.html

https://www.corvetteforum.com/forums...m-build-2.html

https://www.corvetteforum.com/forums/c6-corvette-zr1-and-z06/4078466-mamo-motorsports-ls7-package-200-rwhp-gain.html

https://www.corvetteforum.com/forums/c6-corvette-zr1-and-z06/3882550-mamo-motorsports-build-mms-heads-solid-roller-msd-factory-shortblock.html

Eric @ HPR explains what I said in post # 23.
https://www.corvetteforum.com/forums/c6-corvette-zr1-and-z06/4108029-might-just-pull-the-plug-on-a-hpr-480ci-ls-motor-for-08-zo6-2.htm


454 Mamo Top end Vette on e85 making 700rwhp.
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Yes. None of those are the thread I was looking for. Google works for me too. Lol

 

What LSA is that 242/250 camshaft?

 

The cams going to do the most! Willing to bet a solid $100 that if you used the new cam on the old heads and intake or MSD ....your new top end won't be Nothing to call home about. With a ??+ wrhp difference if compression stays the same for both heads. Give a fair difference number.....any 1 Challenger.

Got a trick up my sleeve....° The intake Limits both heads to close #s.

 

114+3. I specced it to drive good and make peak power at 7K. Basically got what I specced.

 

I would take that bet in a second, except it would cost me way more than the winnings to do the tests. Let's see...

~$150 in gaskets minimum
~$100 in fluids minimum
~$300 in pushrods, because I'd need to order a new set of custom length due to base circle change between cams.
~$600 in rockers. I had the ones I ordered set up for 10mm bolts. Can't use on 8mm heads anymore. And I'm not taking stock rockers to 750 lift.
~$100/hr to tune on the dyno.

On top of which, I travel >80% of the time. I will literally get two days at home to swap everything and then if I'm VERY lucky the pushrods I have will work. If not, order pushrods and wait a week. Unless I'm getting sponsored, I'm not going through that. I'm going in for full-on heart surgery and coming out done.

But I will say this much... Let's say I hit 650 rwhp. That would be 73 HP gained. That is not all coming from the cam. It can't be. Especially with ppl saying the sniper to MSD would be a downgrade, not an upgrade. (I disagree on that though. I'll trust what the intake did in reality on my car vs theory.) I could see the cam gaining 70 over a STOCK cam, but it isn't going to gain 70 over the currently installed cam. Here's an example of what I mean...

https://www.corvetteforum.com/forums...post1597995940

You look at that build. Stock LS7 castings ported and set up by Tony. If we are willing to spot that Tony is at least as good as Lingenfelter, this makes a good reference. Cam was 231/243 and made 585/540 on PORTED STOCK LS7 castings. Car made 635/585 on Tony's AM heads with slightly bigger cam at 237 vs 231. Now, are you going to tell me going from a 231 to a 237 cam gained 50 HP?? It didn't. And it made peak power at 6500 RPM. I'm looking for 7000 rpm peak with a shift point of 8K.

Let me ask this... What number would actually impress you? Keep in mind I have a very specific RPM target for peak HP at 7K. So, no using an 8500 or 11000 rpm screamer as a reference. For a 428 to make peak power at 7000 rpm, what would be a good number to you? And don't answer "Do the math" or "It's all up in your head". Give me a hard number that to your mind would be doing something. If you come back with a number like 720 or GTFO, then that's putting me in an RPM band I am not building for.

Here is my reference point. The most powerful NA SBE LS7 on the planet (that I am aware of) runs Darin Morgan heads. These are not stock LS7 heads. They are LSX LS7 heads. Big difference. Makes 704 peak at 7500 RPM and 545 peak tq at 5900 RPM. I want mine to peak HP at 7000. Those Darin heads made 680-ish at 7000 RPM. I'm not saying I think I'll beat that (I don't), but I do think (hope) that this thing is going to impress at the track more so than the dyno. EDIT -- the heads those replaced were Greg Good, which "only" made 680 at 7500 RPM.

Nothing but love and respect for you, but it feels like you're trying to set this up that unless I set a new record, the top end is garbage. And that is neither true nor fair.

 

My 427ci is very mild by those standards than. I was told its all for bottom end/midrange where a streetcar shines. Mine isnt a race car nor will it ever see the track. I will drive it like i stole it tho.
240/250 115+3

 

That is fairly mild for LS7, yes. But I bet it drives nice!

 

I know this one's it 2019. 440 on ethanol 13.4 compression 258/272 114+4 cam..etc Mamo top-end. 704 rwhp with 440 and 13.4 compression.

 

That's not what I said...

Give me a number for my build that to your mind would be a success. And for reference, the SBE NA LS7 record is 704 at 7500 with Darin Morgan LSX-LS7 heads. Prior to that, the same car had 680 at 7500 RPM with Greg Good heads. I'm aiming for 7000 peak. My 428 is only .005" bigger than a stock LS7

 

That will drive really nice.
The valve events are very similar to mine.
i had a 242/250 113lsa +4 at one stage.
With the new solid roller, I have a 52 ivc and 64 Evo on my 408 for a 7500rpm red line. Ivo and evc 12 and 8.
I also read a very interesting article about torque.
The smaller the split the more torque you make as well as getting better under the curve power when it comes to NA applications.
Pat G and Ed Curtis seem to spec their cams this way.

 

Not at all impressed with the torque curve.
Falls off too quick.
Mamos builds usually have torque curves as flat as a pancake with minimal drop off in the top end.
Something isn't right.

 

670 +rwhp is with the new cam and MSD. What r Those 265 heads and 2.30 valve going to be a 30 rwhp or 50+ @ the crank improvement with using the same msd intake and same compression? That 700rwhp Mamo build was 13.5 compression on corn with a 440.

 

Yup. In your other thread that is why I kept saying to ignore splits and look at valve events.

Difference is I am ripping that cam out because I want to run nines. Edit -- if I didn't care about being able to drive it, I'd go 262/276-110+3

 

There will not be an as is with new cam. That was part of the point of the larger post. It will cost me too much in time and money to piece meal it.

So if I do 680 my build is not a turd?

 

Smokey please post a build thread of your engine and show us what you can do.
You seem to bag out everything that is not max effort and you're expectations are kind of unrealistic.
I have read so much information that you have posted but have not seen any evidence from your end.
I'm sure I am not the only one who wants to see your theories put into practise.
Build an engine!

 

Hell no Darth.......But with the better head you can't even get the extra hp potential. Why because of the intake....Was there ever a head test using the same low profile intake with all test. If so look at the best heads tested vs others no major hp diffence.

On way to make some $ to finish my 408...btw.
Think it about it like this if you had 2 heads ones better flowing 400+ and you have heads that flow 380's. Now you have a intake that gets 370's. What will either head flow? Velocity may be up thru the runner but you can only get what sitting on top.
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I hear you. I really do. But keep in mind my RPM target. Peak power at 7K RPM. Most of those intakes you're talking about make power via RPM. Part of the issue with the damned sniper. it wants to peak at higher RPM, but sacrifices port velocity to achieve it, so the torque numbers suffer.

Also, let's look back at the 704 HP Darin motor for a second:

Quote:

• Solid Roller Cam by Bullet Racing Cams

If I pull off 680, figuring I will have smaller cam, plastic intake, smaller exhaust, I'll be thrilled. This same build made 680 with Greg Good heads and a sheet metal intake. So take all of that stuff with Greg Good heads, it made 680. Which is sensational.

My point is this -- if I get similar numbers, why should I think the intake is holding it back?