jason99frc

iTrader: (12)

OK I just upgraded my LS2 427 from LS6 / Fast 90 top end to LS7 CNC HEADS, PORTED LS7 INTAKE, BIG CAM 251/267 .660 and it made great power on the first pull (564 RWHP) but the KPA reading was dropping to 95. Removed the green filter from the Vararam and stuck the fan right @ the air scoops and power jumped to 570 and KPA only dropped to 97. I also run twin QTP cutuots which were only open to ~ 25%. I will re-dyno tomorrow to see if the exhaust restriction was causing any of the problem.
but If I add a 100mm MAF must I ditch the Vararam VRB2 and buy an air intake system specific for a 100mm MAF?

Hopefully someone here has been through this.

Thanks,

Jason @ TSP r u working today? call me if you are

jason99frc

iTrader: (12)

Alright, I know one of you tuners out there has been through this!!!!!!

JUNK

U are using the LS7 intake manifold, the intake duration on that cam is a bit much for that intake. 244ish would be about the max assuming an aggresive lobe. W/ good heads, we have made 589rwhp using a 239deg and the torq was on sooner. I have run what is now known as the Ragin' Racin' Striker cam (243/257), and currently run a 233/276 630lift cam. Depends on the use and how streetable u want to be I suppose. Don't bother w/ sheet-metal type intakes, u will be happy w/ the kpa issue and pissed about everything else. Don't look to get N/a #s much over 600rwhp using that intake, and if u do, check for error, then get back to me (and let me know how the hell u did it!)

jason99frc

iTrader: (12)

Junk,
I appreciate the feedback.
I didn't want the low end TQ as it just makes it harder to maintain traction on the street. I wanted max hp gain @ 6000+ , I gained nearly 100 rwhp @ 7k.

Shawin @ Ragin and I talked in depth about this cam and it is so much nicer to drive than my old 248/254. Comp Cams did a lot of research and testing on these new rectangular specific LSL grinds. I know the Katech grind u run is great, I just needed something a bit different.
I think you mis understood my initial post, I need info on a 100mm maf and air intake not intake manifold. What Maf r u running?

The Dragon

iTrader: (6)

ttt . . . I'd like to know just to satisfy curiousity

ringram

Why not lose the maf altogether and try speed density, then you have zero restriction until the TB and Intake. (Assuming your airbox and filter are ok)

bandit1

iTrader: (12)

speed density here and loving it much better than MAF in my book

98Z28CobraKiller

iTrader: (17)

My buddies car has gone 9.9 in the 1/4 on motor with an 85mm maf. Don't waste your money. Same car has been 8.89 on spray.

You will get different map readings due to the different map sensor location. Don't put too much thought into that.

tektrans

iTrader: (23)

I've gone 9.5 N/A in the 1/4 with my 85mm maf (and my stock ported L76 intake for that matter) ,Cobrakiller has a good point, spend the $$ on something else.

jason99frc

iTrader: (12)

Stock CPU w/ SD is for those that don't want to take the time or lack the knowledge to tune a car with a MAF. If the stock CPU would allow for the use of a wide band monitor and make adjustments accordingly then great but I drive this car a lot in many different environments and the adjustments, TO ME, are necessary. Last month I left Orlando @ 10 pm and it was 70 degrees, by 9 am I was near Cincinnati and it was 10 degrees. I dont drive my car easy and the cpu needs the input or damage will occur with those types of changes.
For what its worth - I did tune my car in SD,but that's there as a safety net in case the MAF fails. 6-8 hours driving and SD tuning then hook up the MAF and do it again. Drive ability and safety all done in 1 long day. Next day hit the dyno and make minor changes for a little extra power.

RINGRAM - The above is not meant as mean I just needed to explain why the MAF is there and why I need it. Chances are that It may never make a difference but I'm a gambler and I do what ever I can to improve my odds against failure....

jason99frc

iTrader: (12)

98 Z28COBRAKILLER & TEKTRANS,
My thoughts as of now are to leave everything alone, do some fine tuning, and wait for a better LS7 composite intake and then change everything( INTAKE, TB, MAF & AIR INDUCTION SYSTEM)

I think we can still get 580 - 585 with some extra tuning but 570 is still fine.

ringram

Actually to do an SD tune takes longer than just messing with one MAF column. You have a whole VE table to get right as well as the intake temp blending.

The MAF makes the job easy and is to a certain extent self adjusting. However at low airflow SD is blended in due to its superior and linear performance.

Each to their own. Nobody will hang you for using the MAF, but plenty of tuners prefer SD only for the ultimate in performance.

tektrans

iTrader: (23)

My buddy Rick (Firehawk441) just put a new motor in and it's being tuned by Cartek (my tuner as well) and it's a solid roller 454, aluminum rods, Beck sheetmetal intake etc. and Cartek did an initial tune and they told Rick he needed the 100mm maf and bigger throttle body.
So I guess for the hydraulic set ups like yours and mine the smaller stuff is still ok but throw in a couple more cubes, compression and a lighter rotating assembly and it's time to step it up.