Retune after porting FAST??
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Chad
You have a tune from ONE OF THE BEST IN THE BUSINESS (SLOWHAWK)> I'm quite sure that porting the intake will increase intake efficiency but, it's difficult to say how much it will effect the Volume metric Efficiency (VE) tables. Thats the major thing thats going to change if you port your manifold. I recommend you contact Tony Mamo and ask him what he recommends, Hes very honest and straight forward and will lead you in the correct direction. I'm sure SLOWHAWK will top off your tune if its necessary.
On second thought, NA,,,don't tune it. That way it will be easier to have any chance to beat ya!
Who's going to port your manifold????
Bill C
Thread Starter
Le Mans Master
Joined: Feb 2001
Posts: 6,777
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From: West "By God" Virginia
CI 7-8-9-10 Veteran
Thanks BC!!!
I have already talked to Tony Mamo, and he suggested I go with a whole new ported 92 setup. Obviously, I would need to retune after that, but I am not going that route when Mamo's tests have shown only a 5hp gain over my current FAST 78 setup. That would be a lot of $$ for very little gain!!
I will pm Don and see what he thinks!!
As for outrunning me, I don't think your clutch will let you!!
I have already talked to Tony Mamo, and he suggested I go with a whole new ported 92 setup. Obviously, I would need to retune after that, but I am not going that route when Mamo's tests have shown only a 5hp gain over my current FAST 78 setup. That would be a lot of $$ for very little gain!!
I will pm Don and see what he thinks!!
As for outrunning me, I don't think your clutch will let you!!
Thread Starter
Le Mans Master
Joined: Feb 2001
Posts: 6,777
Likes: 358
From: West "By God" Virginia
CI 7-8-9-10 Veteran
Race Director
Joined: Mar 2001
Posts: 11,405
Likes: 26
From: Whippany NJ
CI 6-7-8-9 Veteran
St. Jude Donor '08-'09
NCM Sinkhole Donor
Chad- I would definitely have the AFR checked after the port work especially if you did serious porting to the FAST. A few years ago after my h/c was done, I purchased a breathless performance air duct and installed it...i said to myself that little part swap wont do jack to my tune. I then happened to go to a dyno day at some other tuner shop My afr was leaned out some! 
Took it back to ECS and Chris made some adjustments to the fuel and it was back to 12.9
Took it back to ECS and Chris made some adjustments to the fuel and it was back to 12.9
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
CHAD,, "MORE MODS!!! That would mean duel turbos or a supercharger!
Chad
I have decided to get a SPEC duel disk and I will install it this winter. That should take care of that small issue!
BC
Burning Brakes
Joined: Oct 2005
Posts: 1,176
Likes: 0
From: Suffolk Va
Thanks BC!!!
I have already talked to Tony Mamo, and he suggested I go with a whole new ported 92 setup. Obviously, I would need to retune after that, but I am not going that route when Mamo's tests have shown only a 5hp gain over my current FAST 78 setup. That would be a lot of $$ for very little gain!!
I will pm Don and see what he thinks!!
As for outrunning me, I don't think your clutch will let you!!
I have already talked to Tony Mamo, and he suggested I go with a whole new ported 92 setup. Obviously, I would need to retune after that, but I am not going that route when Mamo's tests have shown only a 5hp gain over my current FAST 78 setup. That would be a lot of $$ for very little gain!!
I will pm Don and see what he thinks!!
As for outrunning me, I don't think your clutch will let you!!
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Thread Starter
Le Mans Master
Joined: Feb 2001
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From: West "By God" Virginia
CI 7-8-9-10 Veteran
No, the ported 90 only yeilds 5 hp more than the ported 78 overall. Not only a 5hp gain. I forget what the overall gains were, something like 20whp for a 78, and 24-25whp for a ported 90.
Thread Starter
Le Mans Master
Joined: Feb 2001
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From: West "By God" Virginia
CI 7-8-9-10 Veteran
Found this reply from Tony Mamo in another thread...
Russ...
Your ported 78mm FAST will make 5 HP more than an out of the box 90mm....unless you port the 90 as well you will be going backwards. You will only see a 5 RWHP bump in power with the 90mm ported but your throttle response will improve dramatically.
When the smoke clears on the dyno however, the difference between one of my ported 78 units and ported 90's isn't very much. There is probably a better way to allocate those funds IMO....your going to spend alot of money for 5 ponies or so (ported 90 mm intake plus ported LS2 90mm TB, etc.).
My original 346 build made 475 RWHP with the ported 78 FAST....480 with the addition of the larger 90mm unit.
If your starting from scratch I feel the 90 is a good move....but already invested in a ported 78 its probably not unless you simply have to have every last pony and are willing to pay for it (or have a buyer giving you a decent buck for your original set-up).
Keep the 78 set-up, get a larger cam, add some compression, fly cut your pistons, and run a set of Yella Terra ultralite rockers....that will certainly wake up your combo.
If you need some advise you know where to find me...
Tony
Your ported 78mm FAST will make 5 HP more than an out of the box 90mm....unless you port the 90 as well you will be going backwards. You will only see a 5 RWHP bump in power with the 90mm ported but your throttle response will improve dramatically.
When the smoke clears on the dyno however, the difference between one of my ported 78 units and ported 90's isn't very much. There is probably a better way to allocate those funds IMO....your going to spend alot of money for 5 ponies or so (ported 90 mm intake plus ported LS2 90mm TB, etc.).
My original 346 build made 475 RWHP with the ported 78 FAST....480 with the addition of the larger 90mm unit.
If your starting from scratch I feel the 90 is a good move....but already invested in a ported 78 its probably not unless you simply have to have every last pony and are willing to pay for it (or have a buyer giving you a decent buck for your original set-up).
Keep the 78 set-up, get a larger cam, add some compression, fly cut your pistons, and run a set of Yella Terra ultralite rockers....that will certainly wake up your combo.
If you need some advise you know where to find me...
Tony