G Atsma

If the MAF IS 85mm and all other parts of the system are larger, especially the throttle body, the MAF IS the choke point of the system. This isn't rocket science. I don't know what your tuner is thinking, but physics is physics. If the throttle body is 102mm and is required to feed the engine in question, don't you think an 85mm part in the system will restrict it a bit??

SoFla01SSLookinstok

I agree with you guys. It will not make the most power it can with the 85mm maf. But I guess just going off a friends results. He was still on the ls6, stock maf, slp lid, & 1 3/4 headers. I also have an 85mm maf on a fast 92 setup. Which I guess you might say isn't as bad cause 92mm. Also lots of people say my car is slow too so..

Also hoping the compression is up above 11.

G Atsma

You have to agree that an 85mm MAF in front of a 92mm TB isn't as bad as the same MAF in front of a 102mm TB, which is what the OP has. The contrast is greater.

Darth_V8r

iTrader: (4)

Yeah I am being a dick but I am not.

I think the stock ls7 makes 505 crank hp. Your motor should do better than that. Stock ls7 uses 102mm maf. Its the diff between 3.5 and 4 inch. Rough numbers.

But you lose laminar flow by necking down. You have phenomenal heads on that thing and a pretty spot on cam. That mill can move some air the way you are setting it up. Then you set it up to breathe through a straw. And exhale through a straw. Even on my old 346, I was glad I ditched the maf. All you gotta do is log map at key on engine off and compare to map at WOT. If there is a big kpa drop the maf or intake tract in general is choking it back. Ditched the maf, gained 4 kpa. Thats over half a psi. And that was a 100 mm maf

So do I think you will be higher than 430? Yes, and I hope you do get awesome numbers and prove me wrong.

Do I think you will end up upgrading your intake and exhaust? Yes

Am I drunk enough to answer my own questions? Apparently.

But my magic eight ball says you will end up doing a straight 4 inch CAI and going SD.

danny_6725

iTrader: (10)

I do and that's why I was considering a SD tune or going with a bigger MAF. What turned me away was the fact that my tuner said I wouldn't see gains from doing so. I believed him since he's supposed to be one of the best tuners in the east coast

danny_6725

iTrader: (10)

I do have a 4" intake on it now, not duals, just single. However, I had to run the adapters to fit the 85mm maf to the larger piping. As for exhaust I'm running turn downs. Not the greatest ones, but they did the trick for now and were cheap. Purple hornies, which I believe are 3.5" at the header flange, then neck down to 3" and back to 3.5" if I'm not mistaken.

I do completely agree with you, I guess it's time to talk to a few other tuners in my area. Might go SD after all, like I originally planned to.

G Atsma

Just to give the tuner the benefit of the doubt, I bet he's an old-school tuner from before computers and is a whiz with carbs and distributors, and back in the day, anything that measured 85mm would pass enough air to feed a healthy small block. He should retire, or get with the times. And I'm not a smartass kid. I'm a smartass old guy of 66. lol

danny_6725

iTrader: (10)

Let's just got with that lol. I don't want to throw dirt on his name without giving him the chance to make his statement himself. Either way I'll post up the numbers when I get it tuned. Waiting for the weather to break a bit

G Atsma

Great! Looking forward to it! Let's get those big numbers!

ddnspider

iTrader: (26)

Anybody actually see 20whp or more from a MAF restriction? Acting like the MAF is the end of the world, anybody have back to back graphs? Don't show me a graph where the TB/intake/LID/etc was all swapped with the MAF.

LaBLKv6Z

iTrader: (13)

I'll guess 480/440 on a loaded dyno. What dyno will be used?

My old setup:

TSP 2.5 LS6 Heads
Stock LS1 bottom end
TSP MS3 cam
1 7/8" TSP longtube headers
Dorman LS2 intake, 92mm TB
Stock MAF 75MM
M6
SE 3" duals


Loaded dyno made 438/420
Unloaded dyno made 480/436

Car trapped 119-120's.

SoFla01SSLookinstok

It would be cool to see a swap of just the maf. Maybe can find some results of the 100mm maf swap. But as you said it's usually not the only part changed in the induction so really cant tell off "just" maf swap. What I've found over time with your help of coarse. The air box itself is a restriction on these cars. Even after cutting open for FRA as you told me. That did help a bunch. Saw more even maf readings & lower manifold vacuum. The air box is still a limiting factor.

I'm not debating that it wont make more power with a bigger maf. The question is really how much. I don't think just that change will be that big. As I like to say. There's only one way to find out.

Is the air box cut open at all or just pulling in the factory front inlet?

thunderstruck507

iTrader: (18)

The difference between a solid LS1 and a 6.0L isn't phenominal. I went from a LS1 to a LS2, there were gains but nothing extremely jarring even with bigger cam and some extra port work on the heads.

TBH if a car with ls6 intake and y pipe exhaust put down near 470rwhp I'd say that dyno was having a very happy day.

G Atsma

I agree with the above. I think in the OP's case it's a combo of restrictive airbox and too-small MAF. I can see a 20HP loss between them

ddnspider

iTrader: (26)

That is where my head is at.

SoFla01SSLookinstok

I also wouldn't say phenominal. But the bigger piston does help make more power. As it's easier to make 500rwhp with an ls2 than with an ls1.

Trust me. I guess some nice ported 243 heads & a pretty good cam. Not sure on specs but think in 23x/24x range. I was surprised how well his car ran with the supporting mods, ls6 intake, 1 3/4 headers, single exhaust. I myself believe the dyno numbers were close to that as him & I were the best run out of our LS group. It was neck & neck. I think he may be a little lighter but I cant say really. No a/c whatever. Now he is upgrading to fast 102, 1 7/8 headers, & cut out. Cant wait till he's done. Should make a nice difference.

danny_6725

iTrader: (10)

I'm not running an air box / lid style. I'm using a 4" CAI with a cone type filter and with the 85mm maf

danny_6725

iTrader: (10)

Well it depends now. For the tuner that recommended keeping the MAF, it's a dynojet. As for the other tuner that I'm considering for SD, it's a Mustang dyno.

danny_6725

iTrader: (10)

I would like to see this as well. If anyone can provide some back to back comparison, it would be great! Seems like there's some mix feelings going on between the MAF being restrictive enough or not.

thunderstruck507

iTrader: (18)

On my car going from a stock LS1 MAF to the 85mm MAF with a larger mesh honeycomb was worth exactly 0 measureable gains at the time it was done, which was around 420rwhp through an unlocked auto.