LT1 D1sc only making 9 lbs.
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From: Lexington, KY
LT1 D1sc only making 9 lbs. my newly setup 355 lt1 has a d1sc with 7.65/3.4 pulley combo and is only making 9lbs at like 5500 and holding steady at that. any ideas on what to do about this? i think it should be making about 13-14 at 6500 but im not sure.. is my cam hurting me? its a custom blower cam
236/246 .624/.630 114
236/246 .624/.630 114
Thread Starter
11 Second Club
iTrader: (12)
Joined: Apr 2007
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From: Lexington, KY
no idea, the dyno was not reading correctly the day i went... dynod 1568 hp lol.
355 lt1, ported stock casting lt1 heads, ported lt1 intake, twin 58mm throttle body, 1 3/4 hooker long tubes, true dual 3 " exhuast, 9.5:1 c/r, 2.02/1.6 valves, above stated cam..
anything else?
currently rev limiter is set to 6200 because of whatever is causing the boost to stop or drop off.
355 lt1, ported stock casting lt1 heads, ported lt1 intake, twin 58mm throttle body, 1 3/4 hooker long tubes, true dual 3 " exhuast, 9.5:1 c/r, 2.02/1.6 valves, above stated cam..
anything else?
currently rev limiter is set to 6200 because of whatever is causing the boost to stop or drop off.
That's a maxed out pulley combo. Meaning at 6700rpm your impellar speed is 61807rpm of a recommended max of 62000.
I think you may have some belt slip. Boost should keep building with rpm. You can try running the EPP crank pulley that's an inch bigger. That would let you run a 3.8 pulley to put you at 62000rpm at 6650rpm. Or try a 3.4 Reichard Racing pulley.
I think you may have some belt slip. Boost should keep building with rpm. You can try running the EPP crank pulley that's an inch bigger. That would let you run a 3.8 pulley to put you at 62000rpm at 6650rpm. Or try a 3.4 Reichard Racing pulley.
Thread Starter
11 Second Club
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From: Lexington, KY
That's a maxed out pulley combo. Meaning at 6700rpm your impellar speed is 61807rpm of a recommended max of 62000.
I think you may have some belt slip. Boost should keep building with rpm. You can try running the EPP crank pulley that's an inch bigger. That would let you run a 3.8 pulley to put you at 62000rpm at 6650rpm. Or try a 3.4 Reichard Racing pulley.
I think you may have some belt slip. Boost should keep building with rpm. You can try running the EPP crank pulley that's an inch bigger. That would let you run a 3.8 pulley to put you at 62000rpm at 6650rpm. Or try a 3.4 Reichard Racing pulley.
i am going to look into adding another idler on the bracket to get some more belt wrap on the blower pulley.
That's a maxed out pulley combo. Meaning at 6700rpm your impellar speed is 61807rpm of a recommended max of 62000.
I think you may have some belt slip. Boost should keep building with rpm. You can try running the EPP crank pulley that's an inch bigger. That would let you run a 3.8 pulley to put you at 62000rpm at 6650rpm. Or try a 3.4 Reichard Racing pulley.
I think you may have some belt slip. Boost should keep building with rpm. You can try running the EPP crank pulley that's an inch bigger. That would let you run a 3.8 pulley to put you at 62000rpm at 6650rpm. Or try a 3.4 Reichard Racing pulley.
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Verdad Gallardo my newly setup 355 lt1 has a d1sc with 7.65/3.4 pulley combo and is only making 9lbs at like 5500 and holding steady at that. any ideas on what to do about this? i think it should be making about 13-14 at 6500 but im not sure.. is my cam hurting me? its a custom blower cam
236/246 .624/.630 114
236/246 .624/.630 114
Make sure all intercooler clamps are tight.
Try making a run without the air filter installed to see if the filter is causing a lot of restriction. The supplied ProCharger air filter is good for about 12-14 psi on most applications before it gets too restrictive, but it is a good place to start. Just don't suck any debris in there!
Make sure the bypass valve only has a slight air gap when in the closed position. We had one several years ago that had too large of a gap when closed, and we picked up two psi when we swapped it out.
Check for belt dust on the blower to see if you can detect whether the blower belt is slipping. A new blower belt needs to be retightened after a half an hour, as they stretch out. If the belt isn't tightened and it slips, it then has a tendency to slip easier as it gets what I call "greasy".
You might need to remove the intercooler tubing from the blower and at the throttle body, and cap each end of the tubing. Install a schrader valve into one end and pressurize it to check for boost leaks. Caps can be purchased in the plumbing section of a hardware store. You can probably pick up the valve at a local auto store. Several years ago we had a GTO that wasn't making the boost we knew it should be, we found a pin hole in an intercooler weld.
Your valve springs could also be bleeding off boost if they are not strong enough. Hopefully you find the problem, it can be perplexing to say the least. Bob
Did your kit come with the flexible tube that connects to the rear of the supercharger on the inlet side? if so, look at that. Mine back in the day was doing the same thing and the tube was collapsing under boost, I removed it (and like Bob says, make sure there is no debris that can be sucked up), the boost shot up from like 7lbs to around 14 lbs, I made one out of steel but I think they sell them now.
Thread Starter
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From: Lexington, KY
i replaced my air filter today, massive difference in feel of the car havent checked boost gauge yet but i suppose its up 1-2 lbs.
i have the epp hard inlet pipe for the d1sc. got rid of the orange stuff long time ago.
belt slip, oh yes. my pretty new engine was COVERED in dust after like 700 miles of driving. i cranked it down a bit since then and it felt better after doing that (THIS WAS LIKE LAST WEEK I DID THAT).
ANYWAYS, im running 2 6 rib gates belts, think that is hurting me any?
ill report back on boost levels on the way home from work tonight.
thanks guys.
i have the epp hard inlet pipe for the d1sc. got rid of the orange stuff long time ago.
belt slip, oh yes. my pretty new engine was COVERED in dust after like 700 miles of driving. i cranked it down a bit since then and it felt better after doing that (THIS WAS LIKE LAST WEEK I DID THAT).
ANYWAYS, im running 2 6 rib gates belts, think that is hurting me any?
ill report back on boost levels on the way home from work tonight.
thanks guys.
I went from the hard plastic ATI inlet tube to a custom metal inlet tube, and put a large air filter from EPP on it and saw a difference from 9#'s to 14#'s of boost (and about 100 RWHP on the dyno). I didn't have belt slippage because I already had the ASP pulley, but if if you also where getting belt slippage that would just add to it.
Sounds like you have everything worked out, but I thought I'd thow in my .02 cents as I was in the same boat in my D1SC LT1.
Sounds like you have everything worked out, but I thought I'd thow in my .02 cents as I was in the same boat in my D1SC LT1.
I went from the hard plastic ATI inlet tube to a custom metal inlet tube, and put a large air filter from EPP on it and saw a difference from 9#'s to 14#'s of boost (and about 100 RWHP on the dyno). I didn't have belt slippage because I already had the ASP pulley, but if if you also where getting belt slippage that would just add to it.
Sounds like you have everything worked out, but I thought I'd thow in my .02 cents as I was in the same boat in my D1SC LT1.
Sounds like you have everything worked out, but I thought I'd thow in my .02 cents as I was in the same boat in my D1SC LT1.
Thread Starter
11 Second Club
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From: Lexington, KY
basically, i had the front bumper off, and the d1sc air filter setup is right in front of the drivers fender liner. well i drove back from shop (200 miles) with the front bumper off (trailored it there....) and uh.. now i have BIG holes in my fender liners where they rubbed the tires from the wind at 80mph. well ALL that crap caked my air filter.
so...
didnt know it would do THAT with the boost....
edit, k/n 3.5 inlet, 7" long, 5 inch to 4" taper.
so...
didnt know it would do THAT with the boost....
edit, k/n 3.5 inlet, 7" long, 5 inch to 4" taper.
Heres the inlet tube
Here's my air filter (best picture I got, but its still not very good)
