F-Body Europe

I've been considering a Granatelli MAF (or maybe a Straner S2) but need to know the following:

1. There's a Granatelli MAF and a Granatelli "C" MAF for cold air induction. Am I right in saying I need the "C" MAF for the FIPK (the site suggests cold air induction kits or increased flow kits). Summit Racing have these two and a "nitrous" MAF but some sites only have the stock and nitrous MAF's.

2. Has anyone got solid evidence that these things work. Granatelli claim a "conservative" 10-15 hp. As they cost around $350 plus shipping and plus UK tax, it'll be somewhat expensive if it doesn't work. I'll be happy with a 0.1 reduction over the quarter.

3. The Granatelli site also suggests that all my hard work polishing and porting the MAF ends is all wasted as the computer will unlearn the mod after 200 miles and restore the car to what it was before and that I need their dedicated MAF.

Anyone know about these things.

Sorry, I can't help you out with the Granatelli MAF, but I have the SLP 85 mm and I don't have any KR or detonation with the standard Predator tune. Haven't had a chance to get on a dyno yet, but I figure as long as I'm not getting any timing retard the larger flow area must be helping me. The guys on LS1.com seem to like the MAF from Pace Pontiac. I believe its basically an LS6 MAF and is considerably cheaper than the others.

I borrowed a friends last year for some testing .
Test was conducted in 4th gear from 60 to 120 mph. Time to speed test
I did 5 baseline tests for comparison with stock
I did 12 test with granatelli and lid.
I threw the high and the low out. They were way out of the norms .

With the 10 ten test remaining

5 showed an improvement of about .3secs
3 showed a lost of about .5 sec
2 showed a gain of about .05 of a sec.

Since I didn't buy it I did not have the prerequisite of "I spent Money I will feel a seat of the pants improvement.

If there was an improvement I didn't feel it.

What is the time from 60 to 120? Haven't measured myself, but if it was 10 seconds the 2 % gain you are looking for with the MAF would amount to 0.2 seconds. The improvement may have been within your variance of the results.

That is another good point though, a lot of people have had problems with MAF making their car lean and actually running slower. It would probably be a good idea to make sure you can tune your car to optimize the part or at least check if you have KR when you install it.

The reason I looked at the Granatelli is because it offers the 3 levels (stock, after market induction and nitrous) and guarantees no knock. I've been looking at some mag articles on the site and they reckon a 12hp improvement was seen on an LS1 (less than claimed).

The only reason I thought it might be a good idea is that having done the FIPK, knocked off the end of the EGR and ported and descreened the MAF, you would expect some improvement over the quarter and I haven't seen one yet (I suspect that with over 300hp, gains of 10-20hp are going to make little difference) so i considered there surely wasn't a shortage of air going in and certainly more than before so perhaps the MAF might give more fuel.

I suppose I should replace my "works when it wants" wiper motor first. He he. Still can't fathom that one. Dealer says it's the motor but when it stops working, you opertae the wash-wipe and they'll work once the wash-wipe 4 sweeps are complete - although occasionally, they just stop and park and you have to do it again. Wish I understood electrics enough to reason how or why it can do that.

I tried aftermarket ported MAF ends. I got adudible knock. It seems all engines react differently. I second what Bill stated. Without a scan type program to see your KR you may do more harm than good and with out an edit type program you can't adjust for maximum power increase.

I follow the SLP Forum a lot and there have been a lot of posts on there about the MAFs. Basically the consensus is that some cars increase performance and some lose performance, with nothing common to help you determine what yours will do. In general, with a stock engine, the MAF is not reducing the flow enough to hurt your power. The other general advice is that if you change the MAF, most cars need to have special tuning of the computer to really take advantage. The same applied to the porting or removing of the screen. In other words, there is no way of predicting whether you will be better off or not and you could be worse off. Bottom line, until you do some mods that need more air, it's a crap shoot.

I guess I'll run it at Avon Park in April and see if I can get that time down. Then maybe look at a shot of nitrous instead.

First, I'm going to try and get some anniversary stripes as they'll give me at least 75hp.

Just my .02 cents the most effective way to make big power is to use combinations and you will notice big improvements I phased mine in.
Phase 1
power lid/filter
power pullies
power stat
power program
SLP Y-pipe
+ 50
Phase 2
Dynatech long tubes
stage 2 LS6 heads/Custom Cam
LS6 intake
80MM SLP MAF
Custom Program
36LPH injectors
11.1 CR done by a .030 shave on head
+100
Phase 3
ARP Rod Bolts
bigger fuel pump
Venom Nitrous system
+75-200


Lean engines make more power

I value your advice, Hawk, but I'm a bit of a chicken when it comes to replacing the manifolds. It stems from a Mustang I had which always blew from the manifold and I don't trust myself to change them (don't have time) and no-one here would want to do it really. The import costs are prohibitive too, even if you can get a supplier to send something like that.

The power pullies I've heard good and bad about. I read an article in I think it was High Performance Chevy where they had a bad knock problem after fitting pullies. Changing them back to stock cured the problem so I'm wary of them.

What about changing these 2.73 gears out? Is that straightforward (I have ABS). if so, who is a good supplier?

There was recently a "40-70" thread on another forum where you found your best gear and floored it from a constant 40. Best I could do, 2 up and with over half a tank of fuel, Auto held in "2", was around 4.7 seconds (difficult when the speedo is in kmh) which I thought was fairly lame (as the M6 30-50 is said to be 4.5) and about the same as a Merc 500E posting on the same thread. There was a 180bhp Elise that did it in 2.7 and a modified Porsche that did it in 1. something.

It is not that bad but it would take a good afternoon. I would go with a 3:73 and a super yank converter with a manual shift valve body. If I had a auto I would be quicker. But I am still getting 300 miles per tank Manifolds are pretty easy on LS1 with the rubber gaskets.