Fast 90/90 gains on my set up?
01-15-2011, 06:05 PM
#22
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ya i was lookin thru your posts and found this one. its a good thread. ive also been mullin over the idea of just buying a 383 rotating assembly and installing a larger custom cam. i really just want 500 rw. of course i would go with the ported fast along with larger headers maybe a new larger exhaust and all the do dads
01-18-2011, 12:13 PM
#26
Turk,
I talked to Tony Mamo a day or so via PM. He said a ported 90 or 92 setup on a heads/cam car like what we have is worth about 30rwhp over a LS6. Whick IMO is a lot especially considering how much of a power gain that is at the motor.
He said with stock heads it wouldn't be that much, obviously.
I talked to Tony Mamo a day or so via PM. He said a ported 90 or 92 setup on a heads/cam car like what we have is worth about 30rwhp over a LS6. Whick IMO is a lot especially considering how much of a power gain that is at the motor.
He said with stock heads it wouldn't be that much, obviously.
01-18-2011, 12:38 PM
#27
Turk,
I talked to Tony Mamo a day or so via PM. He said a ported 90 or 92 setup on a heads/cam car like what we have is worth about 30rwhp over a LS6. Whick IMO is a lot especially considering how much of a power gain that is at the motor.
He said with stock heads it wouldn't be that much, obviously.
I talked to Tony Mamo a day or so via PM. He said a ported 90 or 92 setup on a heads/cam car like what we have is worth about 30rwhp over a LS6. Whick IMO is a lot especially considering how much of a power gain that is at the motor.
He said with stock heads it wouldn't be that much, obviously.
01-18-2011, 03:17 PM
#29
Turk when I swapped on my lightly ported FAST 92 which only consisted of the openings smoothed of that ridge, I gained 13rwhp on 241s and lost 1 lb ft of torque peak. However, the performance of the car increased dramatically. Cars I just raced the night before and beat by a car I was now beating by 2-3 cars very easily.
01-18-2011, 08:13 PM
#32
Yessir but no runner work was done. If you look at the intake ports on the manifold you will see some small ridges. These were just sanded smooth on mine, no actual trumpet work like nitroused posted above. That is where the real gains come from.
01-19-2011, 06:51 AM
#34
I bought mine already ported this way. However, I did disassemble it and smooth out one port more by wetsanding and let me tell you it took forever! No wonder this **** is so expensive to have ported by someone who knows what they are doing.
Take a look at the 4th pic nitroused posted, specfically at the portion that connects to the intake ports on the heads. See how it is roughed up looking? That is about the extent of the work done to mine which gets rid of a small ridge there . You can see the ridge I'm talking about more clearly with the intake put together. It is basically right where the top and bottom shell come together and leaves that little gap.
This is just an estimation of mine since I have never seen the workings of Tony Mamo exposed on a FAST intake, but I am assuming he does the trumpet work (where the air enters each individual runner) and he does work on the intake port side basically extending the length of time air has to properly atomize before spark. Take a look at any professionally cnc'ed heads and on the intake side you'll see that there are small "ridges" leading into the head. These help to atomize the air better and I am assuming a properly professionally ported intake just extends this ridge into the intake. But like I said this is just me guessing. Maybe Tony can chime in.
I got your PM and I can give you a call later this evening when I get home from work.
Take a look at the 4th pic nitroused posted, specfically at the portion that connects to the intake ports on the heads. See how it is roughed up looking? That is about the extent of the work done to mine which gets rid of a small ridge there . You can see the ridge I'm talking about more clearly with the intake put together. It is basically right where the top and bottom shell come together and leaves that little gap.
This is just an estimation of mine since I have never seen the workings of Tony Mamo exposed on a FAST intake, but I am assuming he does the trumpet work (where the air enters each individual runner) and he does work on the intake port side basically extending the length of time air has to properly atomize before spark. Take a look at any professionally cnc'ed heads and on the intake side you'll see that there are small "ridges" leading into the head. These help to atomize the air better and I am assuming a properly professionally ported intake just extends this ridge into the intake. But like I said this is just me guessing. Maybe Tony can chime in.
I got your PM and I can give you a call later this evening when I get home from work.
01-19-2011, 11:06 AM
#35
Never seen that area well, good to know if I have mine off again. I used a dremel with a sandpaper roll. It made quick work, I took my time so I didn't mess up and finished everything with 1000grit by hand. Took me about an afternoon. I enjoyed it a lot. Makes me wish I could do stuff like that for a living...granted it's not the extensive work that a professional does as I clearly missed the area you pointed out...but I'm proud of it for a little do it yourself job.
I did do the runner wedges, didn't go overboard near the ends:
A little porting and smoothing on the runners:
Smoothed the casting ridges on the ends:
I did do the runner wedges, didn't go overboard near the ends:
A little porting and smoothing on the runners:
Smoothed the casting ridges on the ends:
01-19-2011, 11:33 AM
#37
Thanks, wish I had direct dyno results but the best I can do is different dynos.
1st dyno: cam, ported stock tb, LT, exhaust, stock stall, cutouts open, ls1 intake, wait4me mail order tune, street tires, converter unlocked 325rwhp/339rwtq Standard spring, cool air
2nd dyno: in process of tune (1 pull before trans let go), Fast 90/90 as ported above, drag radials, unlocked SS3600stall, cutouts closed, lean a/f (near 14 at tailpipe) 368rwhp/341rwtq SAE Winter, cold
3rd dyno: same dyno as above, added UD pulley, larger mid pipes to exhaust, finished tune to 12.8-13.0 at tailpipe, cutouts closed, converter unlocked 349rwhp/323rwtq SAE hot as hell, overcast, insane humidity, heatsoaked car
Considering the basic changes were the intake, the converter, and eventually the tune...I would say I could write some decent gains in there. It felt like a whole new animal above 4000rpm.
1st dyno: cam, ported stock tb, LT, exhaust, stock stall, cutouts open, ls1 intake, wait4me mail order tune, street tires, converter unlocked 325rwhp/339rwtq Standard spring, cool air
2nd dyno: in process of tune (1 pull before trans let go), Fast 90/90 as ported above, drag radials, unlocked SS3600stall, cutouts closed, lean a/f (near 14 at tailpipe) 368rwhp/341rwtq SAE Winter, cold
3rd dyno: same dyno as above, added UD pulley, larger mid pipes to exhaust, finished tune to 12.8-13.0 at tailpipe, cutouts closed, converter unlocked 349rwhp/323rwtq SAE hot as hell, overcast, insane humidity, heatsoaked car
Considering the basic changes were the intake, the converter, and eventually the tune...I would say I could write some decent gains in there. It felt like a whole new animal above 4000rpm.
02-09-2011, 02:44 PM
#38
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Well, I picked up a Fast 78 on Craigslist, then decided to go ahead & buy a used 90 instead. I had my Fast 78 for sale for a few weeks & couldn't get it sold for a decent price, so I figured I'd just go ahead & keep it & do some work on it & run it as originally planned. This thread was my final motivation, along with some PM's from Thunderstruck. 
Almost done now, just need to put a final sand on it with some fine grit. I know I could have gotten a little more aggressive with it, but I didn't want to remove too much material & end up punching through something.
I also ended up boring my 78 mouth out to 85mm. I have an 85mm TB, 85mm MAF, & 98mm lid, so I figured that would be worth some gains for sure.
I won't need my 85mm to 78mm TB adapter plate any more, so I guess I can just bypass the plate all together? If I do that, my TB cable will be too short on my car. Is there a way to adjust that out? I'm sure I could find out pretty easily, just haven't looked into it yet.
I guess I'll just seal the TB up to the intake with some RTV since I had to cut the ring gasket out to bore it. Any ideas here?
Also, the gasket for the top shell of the Fast came off in great condition, so no probs there. That said, any tips for installing the other 2 pieces together? It seems like mine didn't have any gaskets at all. It was more like RTV in there. Should I just line everyplace up with RTV that would normally have a gasket? Then just clean up the RTV that squirts out after I bolt it back together?
Thanks again everybody!
Almost done now, just need to put a final sand on it with some fine grit. I know I could have gotten a little more aggressive with it, but I didn't want to remove too much material & end up punching through something.
I also ended up boring my 78 mouth out to 85mm. I have an 85mm TB, 85mm MAF, & 98mm lid, so I figured that would be worth some gains for sure.
I won't need my 85mm to 78mm TB adapter plate any more, so I guess I can just bypass the plate all together? If I do that, my TB cable will be too short on my car. Is there a way to adjust that out? I'm sure I could find out pretty easily, just haven't looked into it yet.
I guess I'll just seal the TB up to the intake with some RTV since I had to cut the ring gasket out to bore it. Any ideas here?
Also, the gasket for the top shell of the Fast came off in great condition, so no probs there. That said, any tips for installing the other 2 pieces together? It seems like mine didn't have any gaskets at all. It was more like RTV in there. Should I just line everyplace up with RTV that would normally have a gasket? Then just clean up the RTV that squirts out after I bolt it back together?
Thanks again everybody!
Last edited by osuhog; 02-09-2011 at 02:56 PM.
02-09-2011, 03:17 PM
#39
Looking pretty good man, go over all the places with some fine grit and it should come out great.
For the TB cable I'm not sure about the stock one but my Lokar is adjustable both on the sleeve and the cable itself.
For the intake to TB gasket you could buy a sheet of gasket material and cut one out or like you said, a thin smoothe layer of RTV should make a suitable gasket.
The internal seal between upper and lower shells can be reused, there should be drops of RTV in the corners of each piece. Try to pick off as much of the old RTV as you can without tearing up the gasket, then place it into the shell and put new drops of silicone into the corners again.
I don't recall whether there was anything between the 2 lower pieces, but I did put thread sealer on the bolts and a drop of rtv over the heads to keep them from backing out.
For the TB cable I'm not sure about the stock one but my Lokar is adjustable both on the sleeve and the cable itself.
For the intake to TB gasket you could buy a sheet of gasket material and cut one out or like you said, a thin smoothe layer of RTV should make a suitable gasket.
The internal seal between upper and lower shells can be reused, there should be drops of RTV in the corners of each piece. Try to pick off as much of the old RTV as you can without tearing up the gasket, then place it into the shell and put new drops of silicone into the corners again.
I don't recall whether there was anything between the 2 lower pieces, but I did put thread sealer on the bolts and a drop of rtv over the heads to keep them from backing out.
