Domexitium

iTrader: (1)

Just curios, when you guys get the fast 90/90 set up, do you get a bigger MAF sensor?

socmguy

iTrader: (18)

you don't need to.

slow95z

iTrader: (33)

what did that have to do with a fast 92?

tcr98taws6

I did, went to a 100 MAF

Domexitium

iTrader: (1)

haha sorry man i meant any fast 90mm and up, set up. It just seems like it would be rather counter productive, if you had a 90, or 92mm FAST setup, with a stock MAF.

DocEwww

iTrader: (1)

You don't HAVE to...you're still going to get gains out of the FAST intake wether you upgrade the MAF and lid to 85mm or not. If you have the money, go for it. Just make sure you get tuned when you change the MAF.

I upgraded to a 85mm SLP MAF when I did the 90mm FAST intake. Now I'm SD tuned.

needadvice

There's always a "weakest link" in a system. It only makes sense to get a bigger MAF if you're going to open up the TB. Match everything and you'll get the most gains. Including a larger lid opening.

Domexitium

iTrader: (1)

does anyone know where to get a larger lid?

Fifedogg

iTrader: (15)

Fast Toy's sells a nice 85mm Lid. I would get the 85mm 02-04 Z06 Maf.

Jeff@TotalPerformanceEng

iTrader: (6)

PURE snake oil..

Just because something is larger, does not make it better. (Unless its on your wife)

Its about what your intake system flows as a whole. And in 99.999% of all instances an 85mm MAF does just fine.

I have a LSx 454 running a ported 92mm FAST, with TFS 245 heads.Its safe to say, my **** flows some air..

I have tested the following on the SAME motor:

Ported FAST 90mm w/ 85mm MAF
Ported FAST 90mm w/out MAF

LME Sheetmetal Intake w/85mm MAF
LME sheetmetal Intake w/out MAF

Ported FAST 92mm intake w/MAF
Ported FAST 92mm Intake w/out MAF

EVERYTHING was the exact same on the car. This was the EXACT SAME MOTOR on both the dyno AND street. As well as data logged the entire time.

The MAXIMUM additional flow I got was 1KPA just before WOT on the sheetmetal w/out the MAF. Other than that, there was ZERO additional flow

As far as MAP graphing went.. They were almost exact at every data point..

So in my opinion, there is ZERO reason to go with the larger MAF. But my opinion is based on FACT..

I am also running a ported LS2 TB with a halltech airbridge and HUGE K&N filter.

aNuBiS

iTrader: (25)

Interesting

Drake02

I have the stock MAF with a ported Fast 90mm and NW 90mm TB. No problems here with the stock one... my gains were also pretty damn good.

needadvice

But you also have a set of heads there that can't even begin to feed 454 cubic inches. So all of these combinations you're trying are sitting on top of an engine that is essentially less cubes than 454ci. If you had better flowing heads where the engine could eat up more airflow you would see better flow numbers and MORE power with the larger MAF, TB, intake and heads.

You tried a sheet metal intake on top of heads that can't pass the air along to the engine, so the engine never sees the air flow the sheet metal intake is delivering. Your weak link is the heads. You'll make the same power with 422ci. if you use those heads.

When someone puts together a 454ci, with a sheet metal intake (all the plastic intakes flow crappy comparitively), with a 101mm TB and a 101mm MAF (or no MAF, just go SD tune), heads that flow 400 cfm @ .650, and a medium to aggressive cam......you'll see a 700 RWHP powerplant.

aNuBiS

iTrader: (25)

a 245cc head is too small for 400+ cubes? Wow, now I feel shitty about my 225cc heads.

I dont know what a stock maf flows cfm wise, but I still wouldnt believe it would flow enough to feed those heads with a sheetmetal intake.

needadvice

The 245's flow less than ported LS7 heads, especially on the exhaust port. I don't think 454ci cubes can be fed by 245's to the max potential of 454ci's, no way.

I agree, a stock MAF will be the beginning of a poor top end, especially if you have a 454ci.

454ci's need no MAF's (SD tune), 100+mm TB's, than an intake that can flow, then heads that can flow much more than the 245's can, IF you want to be able to properly feed 454ci's.

Its like a guy here I know who has a 427ci LS6 with ported LS1 heads, ported LS6 intake, stock TB and a Z06 MAF. ......Do you think those 427ci's are being properly fed....NOPE!!!! He's got the equivalent of a 383ci breathing OK. His 420 RWHP proves it. He should be way over 500 RWHP with a proper top end.

Domexitium

iTrader: (1)

so whats the optimum heads and intake to use on a 454 and up?

needadvice

In my research and talking with builders that build big cube engines, its all about how much money you want to spend of course, but......

454ci + sheet metal intake or carb style intake + ported LS7 heads + 105mm TB + no MAF (SD tune) + medium aggressive cam in the low 240's = 650-675 RWHP through an A4, 700 RWHP through an M6.

And don't let the talk about "losing low end torque" by using a sheet metal intake suck you in, its simply not going to be noticable. You'll still be putting down 600+ RWTQ in the mid range rpm's, which is all anyone needs for a street car.

There's a few 427ci F-Body's running around here that some guy in Miami builds for people in his garage at his house, he always uses that cheezy "LS Spyder" sheet metal intake (which still blows away any of the plastic intakes) with 90mm TB's and ported LS6 intakes, and SD tunes them all himself....they're all around 560-580 RWHP, for 4-5 years now. Pump gas, 11.3:1 cr. Its all about the better intake feeding pretty decent heads. Imagine if you had a good sheet metal intake feeding 400 cfm LS7 heads through a big 105mm TB and no MAF?????? Ported LS7's flow about 70 cfm more than ported LS6's, which right there is good for about 105 more HP.(70 x 1.5 = 105 hp)

Thats how I see it, but its all about cash. But still 454ci is alot of cubes, you're in big block cube territory, a set of heads that flow 450cfm would even be better because I think even 400 cfm heads still choke the engine some. 400 cfm heads would be the weak link for a 454ci. I think some big block heads flow over 500cfm, so you can see where they are. Cubes are cubes, doesn't matter which block is being used, you still have to feed the cubes. The heads don't know that they are on top of a small block or a big block, their job is the same.

jermzz

iTrader: (18)

First off, the ETP Ls7 4.1 bore heads flow 226 cfm at .600 and the TFS flow 276 @ .600 Etp flows with the pipes off, but it's still not worth 50cfm, and even if it was, it doesnt make the TFS head "flow less."

Ls7 heads look good on paper, but a bigger runner and port doesnt always make for a better head. The poor placement of the valves and size of the ports drastially kills the velocity.

Find me some threads on here with 427 + ci motors making over 600rwhp with ls7 heads. I could post up three off the top of my head that make over 600rwhp and use TFS heads.

Call any of the reputable engine builders and ask them what they think the best head to put on a 454 is. They'll all tell you a cathedral port head, and probably a TFS head. Vengeance, LME, Etc and there's a reason for it.

Either way, a motor with unported, or even ported LS7 heads, will make just about the same amount of power as a motor with a nice cathedral port head such as the TFS if the motor is built right, and for it.

DrkPhx

iTrader: (15)

The best way to tell if you need a bigger MAF is by datalogging WOT runs and recording the MAF airflow frequency. While a bigger MAF certainly flows more air, the most important function it can do is accurately measure airflow in the upper frequency range at WOT. This will ensure the PCM is basing fueling on actual measured airflow and not predicted airflow. If the actual airflow it outside of the MAF frequency table in the PCM, it cannot measure it 100% accurately, therefore it will guess often resulting in a lean condition.

Jeff@TotalPerformanceEng

iTrader: (6)

Let me explain something to you.

ANYONE who knows me, knows I have tried EVERY possible combination in my personal vehicle imaginabe. My "Personal" C5 has seen a stock H/C, Forged 347, Forged 403, Forged 404, forged 408, and finally my 454LSX. Not to mention a P1SC, D1SC, F1R, Kenne Bell 2.6, KB 2.8H, FAST 90 direct port, Sheetmetal direct port, and a FAST 92 2 stage. This has ALL been done in the last 2 1/2 years. Ask LME, They build my motors..

If its one thing I do, is test..

It is not difficult to determine wether or not your heads are flowing adequately. JUST because people throw around LS7 flow numbers doesnt mean ****. I can tell you for a FACT, that my heads are not to small for my setup. I can also tell you that a 26x cam with almost .650 lift is no slouch.

You are making statement on a point that has already been done, and proved otherwise. I know, cause it sitting in my garage..

Currently, I've swapped back to a slightly smaller cam, and a TPE ported FAST 92. Why?? Cause i lost 50+rwtq with the sheetmetal...

BUT....The motor got pulled this weekend for some additional parts testing. So if your willing to put your money where your mouth is, I'll put whatever you want on it. The motor will be at LME next week.

I'm willing to bet the title of my car that with LS7 heads and a 100mm TB, we wont hit anywhere near 700rwhp.., nor will we gain very much more average HP/TQ.