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Hi, I'm finally ready to set my TBSS intake manifold aside in place of a FAST lsxRT, the taller truck version of the lsx 102.
I'm curious if porting is helpful on these if only spinning to 6900-7000 rpm on a naturally aspirated 364 6.0 L (Btr stage 2 cam, 92 mm tb, 10.7:1 CR, A.I. 226 cc CNC 243 heads, 1 7/8" longtubes and 3 " x pipe).
With the TBSS intake, I made 419 rwhp through a th400 auto and ran 11.26@120.64 mph.
I have a 3800 stall so any losses down low over the TBSS intake, are not very important to me.
I ask if porting is helpful on the RT as I read a user saying Phil from Advanced Induction recommended the lsxRT in unported form. Not sure why or how close the 226 cc CNC intake ports are to an unported lsxRT but maybe it's related to that.
I use truck accessories so an MSD isn't an option for me, planning on going through Tony Mamo for the purchase and porting of the RT.
I've contacted him already and don't think he would say it isn't worth it. I realize that there should theoretically be a gain from porting..the question is how much of a gain. It seems like it would be hard to guess but the rwhp increase will tell me how well it took advantage of the porting.
Based on what you describe wanting to spin the motor to 6900-7000 rpm, a Tony Mamo ported MSD is probably more in keeping with your goals than the LONG runner LSXRT. I'd asked Tony and see which he suggests for your build.
I've flow tested my LSXRT & a Tony Mamo ported MSD. The Mamo MSD flowed the best out of the dozen or so intakes tested. Basically, the LSXRT flowed 23 cfm more than the TBSS. The Mamo MSD flowed ~18 cfm better than the LSXRT.
SF1020 bench @28, using same ported head. 4 inch bore
I you want an LSXRT PM me and I will make you a good deal on the LSXRT that was on my 91 RS Camaro and used in the flow test. As poorly as the LSXRT drove on the street on my 383, I won't use the LSXRT on a driver car with a cable TB unless I can build a 427+ LS someday.
Based on what you describe wanting to spin the motor to 6900-7000 rpm, a Tony Mamo ported MSD is probably more in keeping with your goals than the LONG runner LSXRT. I'd asked Tony and see which he suggests for your build.
I've flow tested my LSXRT & a Tony Mamo ported MSD. The Mamo MSD flowed the best out of the dozen or so intakes tested. Basically, the LSXRT flowed 23 cfm more than the TBSS. The Mamo MSD flowed ~18 cfm better than the LSXRT.
SF1020 bench @28, using same ported head. 4 inch bore
I you want an LSXRT PM me and I will make you a good deal on the LSXRT that was on my 91 RS Camaro and used in the flow test. As poorly as the LSXRT drove on the street on my 383, I won't use the LSXRT on a driver car with a cable TB unless I can build a 427+ LS someday.
My timing sucks as I welcome the offer but am literally just about to place a deposit on a ported lsxRT from Tony Mamo himself. I can't use an Msd anyways as I have truck accessories. From all the research I quickly did on these 2 intakes, the consensus seemed to point at the lsxRT for up to 7000 rpm and the Msd if spinning at least to 7500 rpm.
I have a small cam (226/231 .605/.598) and so far it peaked hp at 6250 rpm or so with a Tbss intake. I just spin to 6900 rpm in 1st to maximize my short gear ratio usage and have a better rebound rpm for 2nd.
What I'm really excited for is the rwhp gain and track times as those Advanced Induction 226 cc heads were probably getting restricted by the Tbss intake up high. Saw a 5+ kPa drop at high rpm
If it has the removable Runners like the lsxr I'm going to say hell no it's not worth it. The removable runners have a bell on one end and the other end goes all the way to the flange of the manifold. One solid piece. Well actually it's two halves molded together but it's smooth as hell. Not like the older style where there were ridges in the ports
From the porting I've done on fast intakes hell yea it's worth it. Cross section is typically alot narrower and you can typically straighten the port out a bit. Port alignment sucks on them to. I picked up 14whp goin from a ported ls6 intake to a fast i ported.
A good port matching is all the fast 102 needs. Anyone trying to sell you a $600 port job on a fast 102 is ripping you the **** off. Besides the base and the bottom of the runner there’s not much to port on it.
Thanks for the replies, maybe I'll just go half way between the 2 ideas and get a $250 - $300 mild port job like from Peak Speed or Advanced Inductions. That way if the gains aren't substantial for my setup, it won't feel like too expensive of a mistake.
I already lost 10 rwhp by having the tbss intake ported (nobody on here). The inner tube had portions of the top removed for what seems like such a great idea for airflow to the runners. The top part of the intake was cut horizontally for them to get access and then resealed with aircraft epoxy/adhesive. While still having the stock tbss intake tune in the ecu, I installed the ported intake and had to take out over 2% of fuel at high rpm areas of the VE table in similar iat conditions. It even trapped 1 mph less and 0.12 seconds slower.
Not sure why it didn't gain but even the spark plugs showed a very uneven burn at the very bottom of the porcelain. With the unported tbss intake, the ring around each plug's porcelain base was much more level and consistent as it also was when using the old style truck intake. So maybe the lack of the "tube" was causing some kind of turbulence. The runners themselves weren't touched aside from the entry to them on the inside.
a good port matching is all the fast 102 needs. Anyone trying to sell you a $600 port job on a fast 102 is ripping you the **** off. Besides the base and the bottom of the runner there’s not much to port on it.
Decent results, my current tbss intake was so rough in the runner area, so I look forward to my lsxRT results. I will only have 1 week to use it after install as it has already been below 32°F at night. Next season will be a full one and a good one. I'm so happy to complement my 226 cc CNC heads with the best intake I can use on the market, that allows for truck accessories and the power range of a 6.0 with a 226/231 .605/.598 cam.
Tony is the one who pioneered porting of the fast. He’s also spent his entire career on studying air flow and how to improve it. I am ordering a set of his mms220 heads this week and the intake will soon follow. If you want just a port job you can go with anyone If you want the best ported intake my moneys on Tony
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Fast lsxRT porting...worth it? 
