Don't let him off the hook Chris. 
Psj?
Haha been super busy and this day is getting really nutty.
Did three pulls last week and have to deal with some small problems before it's worth really putting time into the tune, but it did ~500rwhp on 6 lbs so far thru the non lockup T400. We are seeing rpm fluctuations in the datalogger that are not possible, so the some of the wiring is being checked over. The motor pulls great up to 7000 rpms but until we fix the rpm issue it's not worth floggin the car. My old FAST problem is okay now, the FAST w/b is about a point off from the Dynojet w/b which is concidered reasonable.
Did three pulls last week and have to deal with some small problems before it's worth really putting time into the tune, but it did ~500rwhp on 6 lbs so far thru the non lockup T400. We are seeing rpm fluctuations in the datalogger that are not possible, so the some of the wiring is being checked over. The motor pulls great up to 7000 rpms but until we fix the rpm issue it's not worth floggin the car. My old FAST problem is okay now, the FAST w/b is about a point off from the Dynojet w/b which is concidered reasonable.
Actually it made 457 hp at 6lbs of boost,with obvious problems.But we'll get it straightened out once we can get an accurate data log with the fast we'll have a better idea of whats going on 
Thread Starter
TECH Senior Member
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Cool
You guys are tuning based off of the FAST WB in the bung right? I guess you are tuning and changing pullies in increments? Or are you seeing belt slippage?
I would think you could safely setup a base tune with 12#s of boost and work up from there. How come so low on the boost?
Cheers,
Chris
You guys are tuning based off of the FAST WB in the bung right? I guess you are tuning and changing pullies in increments? Or are you seeing belt slippage?
I would think you could safely setup a base tune with 12#s of boost and work up from there. How come so low on the boost?
Cheers,
Chris
It seemed that with the converter flash it was seeing some belt slip but it was hard to tell because the car wasnt running clean.WE are basing the tuning off the wide band on the dyno and the fast system.
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Verdad Gallardo Steve:
-8.0 crank, 2.85 blower
-Blower is in similar location to LT1, and am using similar size belt to LT1, 41.5 belt
-460rwhp thru a T400, 5000 stall, on slicks, 4.11/9 inch
Chris:
-They are using both, their dyno is very accurate
-The way the car is it could probably make 12 psi on pump gas no problem, maybe even 15 psi.
-What I am really after is to eliminate any electrical issues FIRST, then play with making more power, but if the belts burn up and we have maxed out the tensioner I will pull the car and order cogs over the winter, probably the same size as Z8's. I've got no time at all right now to play with and if I did I could not drive it on the street it's 30F I can't log anything safely. So we'll either pull an encouraging number out of it or find that the 8 rib is not going to hold and move on.
-8.0 crank, 2.85 blower
-Blower is in similar location to LT1, and am using similar size belt to LT1, 41.5 belt
-460rwhp thru a T400, 5000 stall, on slicks, 4.11/9 inch
Chris:
-They are using both, their dyno is very accurate
-The way the car is it could probably make 12 psi on pump gas no problem, maybe even 15 psi.
-What I am really after is to eliminate any electrical issues FIRST, then play with making more power, but if the belts burn up and we have maxed out the tensioner I will pull the car and order cogs over the winter, probably the same size as Z8's. I've got no time at all right now to play with and if I did I could not drive it on the street it's 30F I can't log anything safely. So we'll either pull an encouraging number out of it or find that the 8 rib is not going to hold and move on.
TECH Enthusiast
Joined: Aug 2003
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From: Downers Grove,IL
John, Maybe I am missing something here.I don't quite understand how you only see 6psi with that pulley combo if your dynoing a full rpm pull?
Are you dynoing the motor to only 5000rpm or so right now, or are you using a larger blower pulley right now?
Because even in my wildest imagination I can't see a YS trim with a 8"/2.85" pulley combo making only 460-500 RWHP at anywhere near efficient impeller speeds.
I am just trying to understand what you are saying.
Are you dynoing the motor to only 5000rpm or so right now, or are you using a larger blower pulley right now?
Because even in my wildest imagination I can't see a YS trim with a 8"/2.85" pulley combo making only 460-500 RWHP at anywhere near efficient impeller speeds.
I am just trying to understand what you are saying.
Steve- Pulling it to 7000. Using the pulleys I mentioned. Right now the focus is to chase some of the wiring and then focus on making boost. Either the belt is slipping like crazy or the system is leaking. No biggie, it will get there.
Jim and Dan did some pulls last week and i fully expected there to be some problems since everything is new. They'll check the belt for sure the next time they work on it. During street tuning of the FAST the car did not really have traction and they were seeing 3-4 lbs of boost so nobody really got on it. Steve it flatlined at 6 lbs of boost so it instantly made 6 lbs and no more. We'll know more tomorrow or early next week. I wish I could be more hands on right now but work is very busy.
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From: Houston TX (Chicago/Evanston IL)
PSJ- my 8rib set up made 10 lbs of boost at 1/2 throttle to 4500 rpm's. They backed off because the maxed out the MAF and injectors. We pulled it off the dyno and ordered the GEN 7. we made 550-560 rwhp on the several 1/2 throttle short sifted pulls. This is why I am pretty sure my 8 rib pulley's will work and that the d1sc will make 700rwhp or more.
Last edited by Evil Turbo SS; Dec 19, 2003 at 02:36 AM.
TECH Enthusiast
Joined: Aug 2003
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From: Downers Grove,IL
John,
with that pulley combo and a YS Trim+7000 engine rpm you should be seeing near 100+lbs/min mass air flow according to Vortechs flow ratings. Good for ~ 1000 FLWHP.
If it is belt slip, it's MASSIVE! about 50% slippage.
Whatever the problem is, it should be pretty easy to find.
Possible causes could be,
belt slip-MASSIVE
blower inlet or outlet restriction
outlet ducting leakage or leaking bypass valve.
Steve
with that pulley combo and a YS Trim+7000 engine rpm you should be seeing near 100+lbs/min mass air flow according to Vortechs flow ratings. Good for ~ 1000 FLWHP.
If it is belt slip, it's MASSIVE! about 50% slippage.
Whatever the problem is, it should be pretty easy to find.
Possible causes could be,
belt slip-MASSIVE
blower inlet or outlet restriction
outlet ducting leakage or leaking bypass valve.
Steve
Steve,
Absolutely, this pulley combo could make a lot of power but something might be leaking. I know a buddy's car only made small boost when it had a cracked inlet pipe.
I just got off the phone will Lee at ASP and he's never made a cog drive for a LS1 Vortech, so I am sending him some pictures right now. If I am seeing massive slippage we could try a smaller belt (I have 41.5 now) but if that does not work then I will be probably ordering a 78 crank pulley from ASP and running something like a 30 or 32 blower pulley depending on how hard I want to spin the blower (or overspin).
Absolutely, this pulley combo could make a lot of power but something might be leaking. I know a buddy's car only made small boost when it had a cracked inlet pipe.
I just got off the phone will Lee at ASP and he's never made a cog drive for a LS1 Vortech, so I am sending him some pictures right now. If I am seeing massive slippage we could try a smaller belt (I have 41.5 now) but if that does not work then I will be probably ordering a 78 crank pulley from ASP and running something like a 30 or 32 blower pulley depending on how hard I want to spin the blower (or overspin).
TECH Regular
Joined: Nov 2002
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From: Houston TX (Chicago/Evanston IL)
My blower is a d1sc with a internal step up of 4.10:1.
I am using a 8 rib custom pulley. I have a ati keyed crank pulley. The blower pulley's are from ASP. The crank pulley is a 8.5 inch, blower pulley 3.4 inch. The idler pulley is larger than stock (dont know the size.) It seems to be holding good. The way the blower mounts close to the crank allows me to have a short belt. The only problem I can see is with the screw down tentioner. Again we are seeing good boost with a snap throttle. I will keep you guys updated.
PSJ- ASP did a freaking awsome job on my pulleys. Mine were a one-off as well. Everything fit perfect. They even made me spacers to move te bracket.
I am using a 8 rib custom pulley. I have a ati keyed crank pulley. The blower pulley's are from ASP. The crank pulley is a 8.5 inch, blower pulley 3.4 inch. The idler pulley is larger than stock (dont know the size.) It seems to be holding good. The way the blower mounts close to the crank allows me to have a short belt. The only problem I can see is with the screw down tentioner. Again we are seeing good boost with a snap throttle. I will keep you guys updated.
PSJ- ASP did a freaking awsome job on my pulleys. Mine were a one-off as well. Everything fit perfect. They even made me spacers to move te bracket.