New Dyno#'s - WTF is Going On?
What kind of air inlet are you using? Do you just have a large air filter on the D1SC? Or are you making dyno runs with an open blower (no filter). Running ANY intercooler will be a restriction for boost. If you are going to run any intercooler with more than 6-8#'s of boost, you will need a good sized FMIC, as the twin intercoolers from ATI will be maxed out and won't really be able to help support keeping your IAT's cool past that point. The best way to run power wise would be to not run any intercooler, and run a good methanol injection setup instead. This will allow you to run more boost safely as well as more timing keeping your AIT's nice and cool which in turn will keep you away from detonation.
I have the LT1 unit, and I know the ATI setup from the factory is very restrictive, as it cut 6#'s of boost and over 100 RWHP from my dyno runs with and without it on. Just something to think about especially if it is flatlining up top. Other things to consider is your gap size on your plugs, as if it is too big, you could be blowing out spark (also been there and done that). Mine is currently gapped at .28 but originally it was a larger gap, and I couldn't seem to get any power up top because it was blowing out the spark.
Just a few suggestions. I hate chasing problems like this. I have been through it all before and it really sucks. I hope you figure it out. Good luck!
I have the LT1 unit, and I know the ATI setup from the factory is very restrictive, as it cut 6#'s of boost and over 100 RWHP from my dyno runs with and without it on. Just something to think about especially if it is flatlining up top. Other things to consider is your gap size on your plugs, as if it is too big, you could be blowing out spark (also been there and done that). Mine is currently gapped at .28 but originally it was a larger gap, and I couldn't seem to get any power up top because it was blowing out the spark.
Just a few suggestions. I hate chasing problems like this. I have been through it all before and it really sucks. I hope you figure it out. Good luck!
Originally Posted by Zombie
The other thing you could check is your exhaust setup. Are you running through a muffler? Have you tried dropping that off to see what happens?
Thread Starter
On The Tree
Joined: Jul 2002
Posts: 131
Likes: 0
From: tampa fl.
I'm hoping to answer all the questions at once - here's a few pictures that might help.
1st - the air intake for the blower. It's a custom 4" tube thats been welded to the front of the blower and runs all the way to the passengers side to a very big K&N that you can't see in the photo.
2nd - The can has been tuned with HP tuners in the past and had the same falloff and now I'm running BS3 with the same problem, so I don't believe its the tune
3rd- There is no belt slippage - checked the data log and its right on the money - amazingly, no slippage.
4th - Carl, its a 3 bar
5th- the 2nd photo show a custom Spearco intercooler. The nitrous test refered to above was done with the stock twin coolers - have not tried it with the new intercooler.
I did speak with Greg from AntiVenom and he said that it could be lifters and push rods- I'm running stock on both. Any thoughts???
I hope this helps
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I have heard of FAST intakes leaking on FI applications. Depending on how restrictive your setup is, and what pulleys you have for the blower and crank, the D1SC is good to about 18-20#'s of boost (best setup scenario). I have maxed mine out at just over 15#'s. I have a huge intercooler though, as well as a very large cam (big cam=not big boost in some cases), and my heads are only AFR 180's. This will determine the boost level you will be able to attain. If you want a solid 20#'s of boost, I'd look into going for the F-1 unit over the D1SC that you currently have. However, it still sounds like something is going on with your car which won't be resolved until you find the problem.
If you actually look, The combo does make awesome average power.The midrange is insane.
Peak #'s are for Dyno racers
If you want more "peak" #'s you have to change the Cam or raise the comp. or run alot more boost. To me that setup looks real good.
Peak #'s are for Dyno racers
If you want more "peak" #'s you have to change the Cam or raise the comp. or run alot more boost. To me that setup looks real good.
On The Tree
Joined: Apr 2002
Posts: 140
Likes: 0
From: Tampa
For what it's worth Danny, after reading everyon'es reply..and there are all good idea's...just jam a fat cam in there, spray the **** outta it, and hold on! Seriously, that's an awsome set up with a beeee you tee full dyno graph.
It took 18lbs for a SC'd C5 to make over 800rwhp...
http://forums.corvetteforum.com/show....php?t=1677877
http://forums.corvetteforum.com/show....php?t=1677877
Last edited by VINCE; Apr 22, 2007 at 06:54 AM.
im going to put my suggestion in one more time with the addition of one more....
run a BIGGER cam and then ditch the fast intake. i ran the fast before. took some tuning to get the idle good. but after getting the gmpp setup, my idle is great starts up no problem/ doesnt hunt to catch the idle. and @9 psi i have the same hp as you 707rwhp @ 6300 rpms. i cant imagine what mine will hit if i pulley it to 13-15 psi.
btw: im also running true duals through cats and "4" mufflers classic chambered and magnaflows
run a BIGGER cam and then ditch the fast intake. i ran the fast before. took some tuning to get the idle good. but after getting the gmpp setup, my idle is great starts up no problem/ doesnt hunt to catch the idle. and @9 psi i have the same hp as you 707rwhp @ 6300 rpms. i cant imagine what mine will hit if i pulley it to 13-15 psi.
btw: im also running true duals through cats and "4" mufflers classic chambered and magnaflows
Like I said before, I have heard of lots of people having issues running the FAST intake on a FI application. I don't think a bigger cam would help as having too large of a cam can bring down the optimum boost levels (my car is proof of this).
Boost is the easiest way to add the power. Try to pulley it to max out the blower.
Boost is the easiest way to add the power. Try to pulley it to max out the blower.
more boost? he already has more than me yet at the same hp level. 2 cubic inches more, fast manifold vs gmpp carb style, and a smaller cam. so lets look at the real variables here not boost levels. "boost" is a matter of restriction and his setup seems to be restricted.
