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FAST 102 on its way

11K views 74 replies 13 participants last post by  SUPER_GTO_GT 
#1 ·
I have avoided putting a FAST intake on my car because I've always thought they were overpriced (they are) and wouldn't really provide that much of a power boost (we'll see). But I recently had a few spare bucks that weren't needed elsewhere so I thought I'd at least give one a try. I hope it at least meets or exceeds my hopeful expectations.

Car is ready, FAST should arrive tomorrow. I just hope I can get it to fit with the DuSpeed without much trouble. It was all pretty tight with the stock intake.

Say "aaaaahhhhhh!"
 

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#3 ·
There was more oil in the intake than I'd like to see. It was all cleaned up well after I installed the catch can and there is oil in the catch can, but it must not be catching it all. Perhaps I need to remove it altogether for a full tear down and see if anything inside the can is amiss.

I plan to port the 102 if it isn't a good port match on the heads.

Most people I've talked to including the tuner who is going to do the tune have said a 102mm TB at this point would be more trouble than it is worth (stock long block). The TB would be a good upgrade if I put in a cam and/or do some head work so we'll worry about that if and when I do those upgrades in the future. The LS2 TB I have is ported so it works noticeably better than stock.
 
#11 ·
GZ motorsports vacuum pump.

set it up right and it might give you a few more horsepower.

might not be worth it to you for bang-for-the buck, and you have to pull significant vacuum for it to show any gains. it's a great crankcase ventilation system, though.
 
#5 ·
If you're going to port the intake, paint or powder coat that upper shell to match your pretty orange car and valve covers!

I'm with you, keep the stock TB for now if you're still 364CI and not looking to squeeze every little bit out. And on your catch can issue, what can are you using? A quality can makes a difference...
 
#6 ·
I have Fast 102 lsrx, I think it was worth upgrade since I did heads/cam/fast TB and MAF at same time.

I have 105mm Accufab TB and 100mm Lingenfelter MAF

One suggestion, the MAP sensor sits really close to the firewall on back of the fast and mine rubs, I wish I would of got MAP harness extension and put the MAP sensor up front by TB since the FAST 102 you can mount it in rear or front.




 
#10 ·
FWIW, I've had a catch can on my 05 since before my FAST. I will still get oil in the intake, but not nearly as much as before the catch can.

There's really no way to completely eliminate it.
 
#12 ·
The FAST arrived. Looks like a side by side with the LS2 intake shows that the 102 isn't longer than the stocker, or only a few fractions longer if any. This should make the install with the DuSpeed less of an issue.

I was trying to do a real quick test fit on top of the engine. It wouldn't fit down completely. Do I need to remove the rear engine lift bracket from the engine? I think that is what it was bumping against, but I only had a minute to check as I had to get back to work.

I also noticed that the ports at the heads are narrow. The ported ports on my stock LS2 manifold are bigger. This thing can definitely benefit from some porting. The transition from the runners to the base also need to be smoothed out. I plan to do this porting myself. Bummer is this will void the warranty immediately. But, I have to take the top shell off to drill the MAP hole anyway, so while it is apart I'll check how far off the port match is and decide if it is worth it to port it.

BTW, I got this for $880 shipped. Not even Summit could come close to that by a long shot. Even with their price match they still have to charge tax which made a big difference, over $65 worth. The place I got it from was in Louisiana and at this point in time their laws don't require collection of sales tax on out of state purchases.
 
#14 ·
I'll get the bracket off.

Also, the intake included 10 cap head screws to replace the bolts on the valley cover. However, my LS2 has 11 bolts, so does it matter which one I don't replace? I would assume one at the back by the xxx sensor since the manifold won't sit on top of those.
 
#16 ·
Double check and make extra sure you replace all of those valley bolts (except the one back by the oil pressure sensor) with the button head bolts. If not, you’ll crack the intake tightening it down.

Also, the long bolts that hold the intake down don’t need to be tightened anymore than hand tight. You can snap one of them quite easily if you over torque them. I tightened them with a screwdriver handle to ensure I wasn’t going too tight. Took it for a drive, let it cool down, and rechecked all the bolts.
 
#20 ·
Also, the long bolts that hold the intake down don’t need to be tightened anymore than hand tight. You can snap one of them quite easily if you over torque them. I tightened them with a screwdriver handle to ensure I wasn’t going too tight. Took it for a drive, let it cool down, and rechecked all the bolts.
No, sir. Not hand tight.

I always use the same torque spec for the OEM intake manifold bolts.

Just make sure you have a good in/lb torque wrench.
Yes, per FAST instructions, torque is to 89in-lbs. I believe it even says to take it two steps, 44 and 89 I thought. The instructions even have a sequence. No reason not to follow the instructions here, especially in the GTO where all bolts are easily accessible.
 
#18 ·
Well, I got it ported and cleaned and installed. One thing about it rather disappointed me, look at the first two pictures. REALLY bad port matching by FAST. I had pushed the base as far forward as possible to minimize the overlap. My porting basically ended up consisting of removing the edge where the runners attach to the base and opening up the base to the one side where I could hope to match the manifold to the heads. The only way to address the other side would be to have the heads ported. I can see being off a tenth, but this overlap is huge. But if they are all like this what can you do?

I got it installed with only minor adjustments to the couplers between the TB and the DuSpeed. Things are really tight though. The MAP sensor wire won't reach since the FAST moves it up and farther to the drivers side so I'll have to either open the harness or get a short extension. Everything else reconnected just fine. I haven't started it up yet due to the MAP issue.
 

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#19 ·
I had to extend my MAP sensor harness too. Wish they would have included a pigtail extension. Other than that I was thrilled with the improvement on the dyno.
 
#22 ·
How did you extend the harness? Did you just lengthen the wires? I searched the internet widely last night for an extension harness and could not find one. There are plenty of LS1 to LS2 extension harnesses, but the LS1 uses a different plug style at the harness end so that wouldn't work. I'm certainly not the first one needing a short LS2 to LS2 extension harness given how many FAST manifolds are out there.
 
#27 ·
Extended the old fashioned way, cut the old wires at staggered locations, about 1 inch separation, then soldered in 4" extensions used shrink tubing (slide these on before you solder of course) to finish up the job.
 
#21 ·
I went around those manifold bolts probably 6-7 times. The intake gaskets are brand new and took a few rounds to snug down. Most of the early bolts in the sequence were loose through the first 3 rounds. The following rounds were just to get them all snugged down an even amount.

Another disappointment was that two of the screws holding in the runners had no loctite on them. Their instructions say they can be reused a few times with what is on them but if need be add loctite. Well, two of them had no loctite at all and could have come loose INSIDE the manifold. I added loctite to them of course on reassembly.

All the materials provided, manifold, bolts, screws, etc. are top quality stuff but the port mismatch and assembly boo boo haven't impressed me. They also need to update their instructions as much of it is LS1 related. The instructions say to reinstall the fuel rail guards but there is no way they would fit on the FAST.
 
#25 ·
I guess I was wrong, the LS1 and LS2 use the same MAP sensor. Just ordered an extension harness. Hope it can get here by Saturday. My new air filter for the DuSpeed is coming Friday supposedly but given where it is at today I don't expect it until Saturday. I'm switching from K&N to Green.

I wish I'd know about the MAP extension need, I would have ordered one when I ordered the FAST.
 
#29 ·
This is actually the first I've heard that you need a MAP extension for a 102. I had to unwrap mine to reach the back of my 92. Wondering if unwrapping the MAP wiring would also allow enough slack to reach the 102's location up front.
 
#31 ·
This was suggested to me also, but as I unwrapped it became obvious I was never going to get enough to make the connection so I made the extension.
 
#33 ·
I found if I moved the passenger side engine harness to the inside of the fuel rail I could get the MAP connected. Don't want to leave it like this, but I could at least get it started.

At first it didn't want to crank, then took off. Fired right up when it cranked. No fluid or vacuum leaks (pats himself on the back). It ran a tiny bit rough for the first 15 seconds or so and then smoothed out. I let it warm up a minute or two and then went for a short drive. Low end throttle response is noticeably improved. I only went to WOT once and it was fine. The rest was just cruising.

Is there any harm done driving it without an update to the tune? The only thing changed since the last tune is the intake manifold. I do want to find a way to reconfigure the EVAP lines, they are really stressed as they currently sit.
 
#42 ·
As I said earlier, the improvement in low end throttle response is obvious. I'm sure it is making more power across the board, but how much I couldn't say. It certainly drives smooth and crisp like before but with a better throttle response. Maybe the offset on the intake ports is intentional but I can't imagine why. Though I do know that in the big block Chevy world, putting a rectangular port intake on oval port heads thus leaving a huge overlap step from the intake (big) to the heads (smaller) seems to work in some way and boosts power across the board all other things being equal. Of course the rectangular port intake is almost certainly larger in the plenum and runners, so maybe the step just doesn't matter that much. But honestly, why not just make them match? I did pretty much get the one side of each port to match much better and taking out the transition bump between the runners and base has to help. Though, for all I know I made it flow worse! ;)

And to be fair, I looked at my own photos again and the mismatch really isn't that large if you push the manifold as far forward as the locating bosses will allow. BUT, there is a bit of fore and aft wiggle room so it is worth the effort to try to push it as far forward as the set up allows.
 
#51 ·
I also recently installed a FAST 102 along with the XAIR OTR replacing the Vararam. It is my final bolt-on mod in the 10+ years I have owned the car. I am very pleased with the results, and I also noticed a greater lower rpm throttle response as well as a noticeable increase in torque throughout the entire rpm range. The price was the only problem, but I justified it because I am installing the FTI Tigershark cam in the near future. From talking to others who have done this install I decided a tune might net a few more horsepower (5?) and give peace of mind but probably not absolutley required.
 
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