Low Boost

SSG Pate · October 10th, 2011, 04:26 PM

Hey guys, this weekend at the dyno I was only able to produce around 12PSI on a 2.87 pulley non intercooled which yielded some pretty low numbers. Called Vortech today to see if there might be an issue with my blower they concluded NO, And after checking my serial number I found out that I bought the SI trim V-1 instead of the V-1 S trim I thought I had. Even Vortech concluded that my boost level seemed low. The boost build throuout the RPM and stays steady around 11-12 PSI. I should be much higher then that an ideals? I am still on the Stock vortech inlet,. but even at that there is something going on should be higher boost then I am getting.

Shaun03GT · October 10th, 2011, 04:35 PM

The stock Vortech intake could have a hard time keeping up. The acordian hose sucks, and its pretty restrictive. I say, get a powerpipe, or make your own. stal has a nice write up. Even a Procharger intake setup is better then the Vortech.

Scott2001GT · October 10th, 2011, 05:40 PM

Make a dyno pull without a filter and see what happens

blownstang · October 10th, 2011, 06:06 PM

Oh man. That's even worse. Si trim should be pushing close to 20 psi with that pulley.

Shaun03GT · October 10th, 2011, 06:17 PM

What kind of belt? I know u said 107" long that could be to tight and cause slip. I run a 108" drive rite from advanced and works great. A lot of people run 107.38 gatorback on a 2.87

SSG Pate · October 10th, 2011, 08:00 PM

I have a 107 belt and it seems to be just right, Now I called vortech back and they told me it was just an S Trim again I was like shit which one is it. It dont see to be slipping cause the boost stays constant.

Shaun03GT · October 10th, 2011, 08:02 PM

Try running a Drive Rite 108" Belt, see how it does. If its worse, just return it. Ive returned SOOOO many belts and tensioners with no issues or reciepts lol

SSG Pate · October 10th, 2011, 08:02 PM

I will be buying a power pipe tonight to see if the Vortech intake is the culprit. 430 Is low numbers though. I am also going to look into a intercooler, but dont know where to start on that.

stal94gt · October 10th, 2011, 08:04 PM

That is quite low for a v1si trim. Even though it has a low step ratio it still should make 17-18# non ic. I would watch your boost gauge close cause of the needle looks like it is jumpy it could be a boost leak or belt slip. That small of a pulley can cause slip

Shaun03GT · October 10th, 2011, 08:11 PM

Thats what Im saying.

Nitmare67 · October 10th, 2011, 08:16 PM

SI trim should be making north of 15lbs BUT BUT. Everyone is getting caught up in boost and what THEIR motor does. We dont know what your cam specs are, how much overlap there is, how free flowing the heads are, exhaust system.... The Vortech intake is not THAT bad and IS BETTER THAN A PROCHARGER INTAKE. Procharger intakes may flow a little better but they suck hot air under the hood (not good). I didnt read what kind of maf your running but an HPX would work awesome (I run one in a very strange setup) and then just make your own power pipe. Should cost you about 75 bucks. You wont need any fittings on it if your blow through.

SSG Pate · October 10th, 2011, 08:33 PM

Well none the less there are stock cars with stock heads making more power then me so Im not pointing at the heads now I checked all connections today everything was tight. As far as the gauge went it is a good solid boost reading!! I am going with a power pipe, And looking towards an intercooler although this will drop BOOST, I think I can gain some Power!!

stal94gt · October 10th, 2011, 08:34 PM

I would not be worried about low boost numbers if the hp was there to support it. Last build I did put down 458 hp at 5500 rpm 16 degrees timing and 8#the of boost. Sure it was a 5 speed but that was a standard bore/stroke motor with ported heads and stock cams

SSG Pate · October 10th, 2011, 08:34 PM

Originally Posted by Shaun03GT

Try running a Drive Rite 108" Belt, see how it does. If its worse, just return it. Ive returned SOOOO many belts and tensioners with no issues or reciepts lol

I had a 107.5 it seemed to loose as the tensioner was almost all the way extended. The 107 dosnt stress the tensioner to bad looks about right to me.

SSG Pate · October 10th, 2011, 08:36 PM

Originally Posted by stal94gt

I would not be worried about low boost numbers if the hp was there to support it. Last build I did put down 458 hp at 5500 rpm 16 degrees timing and 8#the of boost. Sure it was a 5 speed but that was a standard bore/stroke motor with ported heads and stock cams

The numbers were 431/407 on an auto non intercooled.

stal94gt · October 10th, 2011, 08:36 PM

If your still using the stock bosh bov check it cause it could ne damaged

SSG Pate · October 10th, 2011, 08:38 PM

I have another Bypass valve that seems to be working just fine I have a stiffer spring in it for hogher boost

stal94gt · October 10th, 2011, 08:41 PM

With sc cars you don't use stiffer springs since they need to vent at idle and part throttle

SSG Pate · October 10th, 2011, 08:49 PM

Here is the Bypass valve I am using, I have the middle spring in for like 10-14lbs boost

BYPASS DIVERTER VALVE VORTECH PAXTON SUPERCHARGER | eBay

stal94gt · October 10th, 2011, 08:53 PM

Springs are rated for hg. Turbos require stiffer springs so they don't get sucked open at part throttle allowing for crap to get sucked in. Sc cars vent out constantly so the bov spring needs to be light so it stays open.

October 10th, 2011, 04:26 PM	#1
SSG Pate Premium Member 00 Mustang GT Vert/88 5.0 Join Date: Sep 2010 Location: Tennessee Posts: 1,766 iTrader: 3 reviews	Low Boost Hey guys, this weekend at the dyno I was only able to produce around 12PSI on a 2.87 pulley non intercooled which yielded some pretty low numbers. Called Vortech today to see if there might be an issue with my blower they concluded NO, And after checking my serial number I found out that I bought the SI trim V-1 instead of the V-1 S trim I thought I had. Even Vortech concluded that my boost level seemed low. The boost build throuout the RPM and stays steady around 11-12 PSI. I should be much higher then that an ideals? I am still on the Stock vortech inlet,. but even at that there is something going on should be higher boost then I am getting. __________________ Proud Iraq and Afghanistan War veteran Powered By MMR 4.75L Stroker, Tuned at Kurgan Motorsports

October 10th, 2011, 04:35 PM	#2
Shaun03GT I Post Entirely Way Too Much 2003 Mustang GT 1/8 - 7.92 @ 91.13mph 1/4 - 12.21 @ 115.84mph Join Date: Sep 2009 Location: Weymouth, MA Posts: 13,446 iTrader: 12 reviews	The stock Vortech intake could have a hard time keeping up. The acordian hose sucks, and its pretty restrictive. I say, get a powerpipe, or make your own. stal has a nice write up. Even a Procharger intake setup is better then the Vortech. __________________ Vortech V1 Intercooled @ 11psi 394rwhp/392rwtq @ 9.5psi 415rwhp/400rwtq @ 11psi on Methanol Tuned By: Pete @ Performance Dyno Affordable Supercharger Build Guide Supercharger Info for Noobs

October 10th, 2011, 05:40 PM	#3
Scott2001GT BYAHHHH! 2001 Mustang GT 13.874 Join Date: Mar 2008 Location: Missouri Posts: 14,793 Blog Entries: 1 iTrader: 3 reviews	Make a dyno pull without a filter and see what happens __________________ Precision Turbo\|TurboSmart\|TeamZ\|Strange\|Hellion\|BBK\|SCT\|Edge Converters\|Fairbanks\|CG Fabrications\|Treadstone

October 10th, 2011, 06:06 PM	#4
blownstang Hardcore Enthusiast Join Date: Jun 2010 Location: Chicago, IL Posts: 2,551 iTrader: 1 reviews	Oh man. That's even worse. Si trim should be pushing close to 20 psi with that pulley. __________________ 2003 DSG Mustang GT 5spd Full Bolt On's, Suspension, Built Rear, V1 S N/A: 266/300, 3,550lbs, 13.44 @ 100.5 1.77 60' Non-intercooled: 356/371, 3,575lbs, 12.81 @ 110.47 1.86 60' Intercooled: 362/370

October 10th, 2011, 06:17 PM	#5
Shaun03GT I Post Entirely Way Too Much 2003 Mustang GT 1/8 - 7.92 @ 91.13mph 1/4 - 12.21 @ 115.84mph Join Date: Sep 2009 Location: Weymouth, MA Posts: 13,446 iTrader: 12 reviews	What kind of belt? I know u said 107" long that could be to tight and cause slip. I run a 108" drive rite from advanced and works great. A lot of people run 107.38 gatorback on a 2.87 __________________ Vortech V1 Intercooled @ 11psi 394rwhp/392rwtq @ 9.5psi 415rwhp/400rwtq @ 11psi on Methanol Tuned By: Pete @ Performance Dyno Affordable Supercharger Build Guide Supercharger Info for Noobs

October 10th, 2011, 08:00 PM	#6
SSG Pate Premium Member 00 Mustang GT Vert/88 5.0 Join Date: Sep 2010 Location: Tennessee Posts: 1,766 iTrader: 3 reviews	I have a 107 belt and it seems to be just right, Now I called vortech back and they told me it was just an S Trim again I was like shit which one is it. It dont see to be slipping cause the boost stays constant. __________________ Proud Iraq and Afghanistan War veteran Powered By MMR 4.75L Stroker, Tuned at Kurgan Motorsports

October 10th, 2011, 08:02 PM	#7
Shaun03GT I Post Entirely Way Too Much 2003 Mustang GT 1/8 - 7.92 @ 91.13mph 1/4 - 12.21 @ 115.84mph Join Date: Sep 2009 Location: Weymouth, MA Posts: 13,446 iTrader: 12 reviews	Try running a Drive Rite 108" Belt, see how it does. If its worse, just return it. Ive returned SOOOO many belts and tensioners with no issues or reciepts lol __________________ Vortech V1 Intercooled @ 11psi 394rwhp/392rwtq @ 9.5psi 415rwhp/400rwtq @ 11psi on Methanol Tuned By: Pete @ Performance Dyno Affordable Supercharger Build Guide Supercharger Info for Noobs

October 10th, 2011, 08:04 PM	#9
stal94gt I Post Entirely Way Too Much 2003 mustang v6 ;) slow Join Date: May 2010 Location: eglin afb florida Posts: 10,197 iTrader: 2 reviews	That is quite low for a v1si trim. Even though it has a low step ratio it still should make 17-18# non ic. I would watch your boost gauge close cause of the needle looks like it is jumpy it could be a boost leak or belt slip. That small of a pulley can cause slip __________________ bone stock from the factory!

October 10th, 2011, 08:11 PM	#10
Shaun03GT I Post Entirely Way Too Much 2003 Mustang GT 1/8 - 7.92 @ 91.13mph 1/4 - 12.21 @ 115.84mph Join Date: Sep 2009 Location: Weymouth, MA Posts: 13,446 iTrader: 12 reviews	Thats what Im saying. __________________ Vortech V1 Intercooled @ 11psi 394rwhp/392rwtq @ 9.5psi 415rwhp/400rwtq @ 11psi on Methanol Tuned By: Pete @ Performance Dyno Affordable Supercharger Build Guide Supercharger Info for Noobs

October 10th, 2011, 08:16 PM	#11
Nitmare67 Hardcore Enthusiast Join Date: Feb 2010 Posts: 1,391 iTrader: 0 reviews	SI trim should be making north of 15lbs BUT BUT. Everyone is getting caught up in boost and what THEIR motor does. We dont know what your cam specs are, how much overlap there is, how free flowing the heads are, exhaust system.... The Vortech intake is not THAT bad and IS BETTER THAN A PROCHARGER INTAKE. Procharger intakes may flow a little better but they suck hot air under the hood (not good). I didnt read what kind of maf your running but an HPX would work awesome (I run one in a very strange setup) and then just make your own power pipe. Should cost you about 75 bucks. You wont need any fittings on it if your blow through. __________________ 99 Mustang GT 446rwhp, Vortech Aftercooled, Killer Chiller @12lbs, HPX, 3.73s, MGW, Battery Relocation, Intercooler Tank Relocated, CF DF clutch, Steeda Quick Release Quadrant, 75mm TB, Ported C&L Plenum, Stock PI Cams Advance 4 degrees, Pro Chamber

October 10th, 2011, 08:33 PM	#12
SSG Pate Premium Member 00 Mustang GT Vert/88 5.0 Join Date: Sep 2010 Location: Tennessee Posts: 1,766 iTrader: 3 reviews	Well none the less there are stock cars with stock heads making more power then me so Im not pointing at the heads now I checked all connections today everything was tight. As far as the gauge went it is a good solid boost reading!! I am going with a power pipe, And looking towards an intercooler although this will drop BOOST, I think I can gain some Power!! __________________ Proud Iraq and Afghanistan War veteran Powered By MMR 4.75L Stroker, Tuned at Kurgan Motorsports

October 10th, 2011, 08:34 PM	#13
stal94gt I Post Entirely Way Too Much 2003 mustang v6 ;) slow Join Date: May 2010 Location: eglin afb florida Posts: 10,197 iTrader: 2 reviews	I would not be worried about low boost numbers if the hp was there to support it. Last build I did put down 458 hp at 5500 rpm 16 degrees timing and 8#the of boost. Sure it was a 5 speed but that was a standard bore/stroke motor with ported heads and stock cams __________________ bone stock from the factory!

October 10th, 2011, 08:36 PM	#16
stal94gt I Post Entirely Way Too Much 2003 mustang v6 ;) slow Join Date: May 2010 Location: eglin afb florida Posts: 10,197 iTrader: 2 reviews	If your still using the stock bosh bov check it cause it could ne damaged __________________ bone stock from the factory!

October 10th, 2011, 08:38 PM	#17
SSG Pate Premium Member 00 Mustang GT Vert/88 5.0 Join Date: Sep 2010 Location: Tennessee Posts: 1,766 iTrader: 3 reviews	I have another Bypass valve that seems to be working just fine I have a stiffer spring in it for hogher boost __________________ Proud Iraq and Afghanistan War veteran Powered By MMR 4.75L Stroker, Tuned at Kurgan Motorsports

October 10th, 2011, 08:41 PM	#18
stal94gt I Post Entirely Way Too Much 2003 mustang v6 ;) slow Join Date: May 2010 Location: eglin afb florida Posts: 10,197 iTrader: 2 reviews	With sc cars you don't use stiffer springs since they need to vent at idle and part throttle __________________ bone stock from the factory!

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October 10th, 2011, 08:49 PM	#19
SSG Pate Premium Member 00 Mustang GT Vert/88 5.0 Join Date: Sep 2010 Location: Tennessee Posts: 1,766 iTrader: 3 reviews	Here is the Bypass valve I am using, I have the middle spring in for like 10-14lbs boost BYPASS DIVERTER VALVE VORTECH PAXTON SUPERCHARGER \| eBay __________________ Proud Iraq and Afghanistan War veteran Powered By MMR 4.75L Stroker, Tuned at Kurgan Motorsports

October 10th, 2011, 08:53 PM	#20
stal94gt I Post Entirely Way Too Much 2003 mustang v6 ;) slow Join Date: May 2010 Location: eglin afb florida Posts: 10,197 iTrader: 2 reviews	Springs are rated for hg. Turbos require stiffer springs so they don't get sucked open at part throttle allowing for crap to get sucked in. Sc cars vent out constantly so the bov spring needs to be light so it stays open. __________________ bone stock from the factory!

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