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Old 11-28-2020, 08:45 AM   #201
pcampbell
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Default Vortech supercharger for ~500whp? Si Too big?



Minor issue I just realized the tensioner wonít really take a large pulley because the tensioner uses a 1/2Ē drive square hole to crank down on the belt. If I go larger on the pulley it will cover the square hole unless I go just a tiny tiny bit larger but the clearance is just about as little as I want already.
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Last edited by pcampbell; 11-28-2020 at 08:57 AM.
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Old 11-28-2020, 09:28 AM   #202
stevieturbo
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Make a new pivot bracket with the square or tension adjuster further away.

It's just a simple flat bracket. Bit of time with a grinder would have a new one cut out.
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Old 11-28-2020, 03:05 PM   #203
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Good idea, maybe I can put my plasma cutter to use. I can trace the old bracket and just move the square hole.
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Old 11-28-2020, 03:09 PM   #204
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Obviously if DIY'ing, it doesn't need to be a square hole. Just weld a nut or bolt or something onto the new bracket to allow you to tension it.

But an angle grinder is just as handy, lots of mess to clean up with a plasma. Oddly I just used mine the other day for the first time in about 5 years...
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Old 11-29-2020, 10:43 AM   #205
pcampbell
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Default Vortech supercharger for ~500whp? Si Too big?

I was able to get pretty good tension just by putting my weight into the idler but not sure if itís enough tension. Lots more tinkering to do.

Last edited by pcampbell; 11-29-2020 at 03:28 PM.
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Old 11-30-2020, 12:34 PM   #206
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I moved the bracket and put on the larger tensioner idler pulley to clear the radiator hose. Now the belt is still slipping with the tensioner maxed out. The belt tension is decent , but not huge. Although huge is not necessarily good.

Here's the bracket with the larger idler, positioned so it can swing completely up and out of the way to get the belt on really easily. R&R of belt is like a 60 second process so that is really nice.



I feel like I have some options here:

1) Try a shorter belt. 61.5 instead of 62.0. This will give me more tension with the tensioner maxed out. Cost $9. I'm not super convinced more tension is a great thing though...

2) Try a RPM (Aramid/Kevlar) belt - only comes in 61.5 or 63.0 - 63.0 is too loose. These are actually designed to run LESS tension and do not stretch. $60 or so.

3) Just go 10 rib. I'd really just need to replace 1 idler pulley and replace my passenger side fan because I'm already running 10 rib pulleys on the SC and on the crank. I think I could hold off on replacing the fan for a while since it is cold here now anyway. $60 for belt and pulley.

4) Gear down to a 3.12" supercharger pulley which would obviously draw out the boost to higher RPMs which is effectively less restriction. $109 for a new SC pulley.

I am sort of leaning towards #3 first then #4 if that doesn't work.
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Old 12-02-2020, 05:54 PM   #207
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10 rib parts coming. It was only $40 in a pulley and a belt, so I had to try it. If that doesn't work I can try an RPM (Aramid) Belt. Then if all else fails, I can gear down the SC. One day I will paint these brackets too.

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Old 12-02-2020, 06:21 PM   #208
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A good strong spring tensioner would still go a long way to resolving any slip issues.. Although more ribs is almost always a positive.
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Old 12-11-2020, 06:06 PM   #209
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I got it up & running on the 10 ribs, definitely an improvement but not there. The 10 rib belt is either so much stiffer or slightly smaller, I had to mount the ribbed idler higher up to get it to tighten.

I decided to give the next easier pulley (3.12) a try though. Vortech has one called a "tall offset" which Vortech themselves could not tell me what that meant technically, so I decided to order it up and see for myself.

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Old 12-11-2020, 06:25 PM   #210
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Wouldn't be convinced those slotted belts could offer more traction ?

Although I guess if the belt structure is less inclined to stretch, that aspect would help. Although really you should not be getting any slip with a 10 rib and relatively low power for what a 10 rib can drive.
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Old 12-11-2020, 07:24 PM   #211
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Yeah honestly the belt was for testing the required length more than anything, it was super cheap ($7). I think a straight ribbed belt would be better although the slots are supposed to be good for less than perfect pulley alignment and I'm not sure how perfect mine are. I will keep tinkering!
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Old 12-12-2020, 01:47 PM   #212
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Found this which is kind of interesting - Dyno of the LA Sleeves FA20 stroker with the same Vortech supercharger, also nearly identical pulley gearing that I'm about to switch to, obviously very different motor though but I don't think there is any closer comparison out there.

They are making 408whp @ 17.77psi and 6500rpm and about 440whp @ 7000rpm and ~20psi on e85.

https://www.lasleeve.com/assets/imag...0tK08gF0x4Xv3k

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Old 12-20-2020, 08:13 PM   #213
pcampbell
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Default Vortech supercharger for ~500whp? Si Too big?

I just ordered a Gates "RPM" belt which is supposed to be the best - very little stretch. I also am working on an additional brace to reduce the bracket flex.

Last edited by pcampbell; 12-21-2020 at 05:22 PM.
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Old 01-17-2021, 07:13 AM   #214
pcampbell
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Default Vortech supercharger for ~500whp? Si Too big?

Still waiting on Gates belt.

Looks to me like Iím maxing out my Cobb 255 pump or right on the edge . A little surprised but looking at this chart, I probably need about 64 gph at 62psi and closer to 70 gph at 64psi. Right at the cross hairs of where it is on the edge for 62psi and definitely below it for 64psi.

What I am seeing is afr rising at the top end and not going down when I add more fuel. I had the same experience when I started off using an outback XT fuel pump but it took me a while to figure out the issue.

Iíll probably just do a drop in 340 for now.

http://www.tanksinc.com/pdf/4_series...flow_chart.pdf
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Old 01-17-2021, 11:57 AM   #215
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Quote:
Originally Posted by pcampbell View Post
Found this which is kind of interesting - Dyno of the LA Sleeves FA20 stroker with the same Vortech supercharger, also nearly identical pulley gearing that I'm about to switch to, obviously very different motor though but I don't think there is any closer comparison out there.

They are making 408whp @ 17.77psi and 6500rpm and about 440whp @ 7000rpm and ~20psi on e85.

https://www.lasleeve.com/assets/imag...0tK08gF0x4Xv3k



Something interesting I noticed here. They gained nearly 100hp going from 5500rpm to 6500 rpm. I think their belt was slipping pretty badly after that ,I would have expected 500whp by 7500rpm.
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Old 01-26-2021, 07:07 PM   #216
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I put my Gates "RPM" belt on, on a cold day , promptly pegged my MAF sensor before my set redline even. This is a 3" Outer diameter MAF housing with an honeycomb air straightener.

Will the car drive OK if I swap to a 3.25" OD (76mm inner diameter) MAF housing? I do believe the air straightener helps out with drivability quite a bit but I dunno. Is this too big of a MAF housing?

The other thing question is will it be OK to use a 3.25" OD MAF housing, but reduce it down to 3" AFTER the MAF housing??? I don't think I have room to run 3.25" OD behind the MAF housing to the supercharger. It sounds like in theory I'd get about 19% more top end reading with the 76mm ID housing... so that would get me to around 475 whp perhaps?

fwiw It looks like the Perrin BIG MAF does reduce diameter right after the maf housing.

Last edited by pcampbell; 01-26-2021 at 07:45 PM.
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Old 01-27-2021, 07:51 AM   #217
pcampbell
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Default Vortech supercharger for ~500whp? Si Too big?

Is a blow through MAF something I should consider?
I donít really understand the advantage other than I can do a BOV instead of a BPV.

A fancy PMAS blow through MAF sensor setup is like $300 bucks. They said it is good for way more power than I can make if installed in a 3Ē tube. I am not sure if that is 3Ē ID or OD. Anyway they say 800whp on a 3Ē tube.

Last edited by pcampbell; 01-27-2021 at 07:56 AM.
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Old 01-28-2021, 09:21 AM   #218
pcampbell
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Default Vortech supercharger for ~500whp? Si Too big?

I ordered a 3.33Ē pulley. Itís a pretty big difference in gearing compared to 3.12Ē. This one will put the compressor impeller at 55000 rpm (20? 21? Psi) at 7300 rpm instead of 6850rpm.

Iím having some weird ecu issues I need to figure out.

Idc and pulse width arenít increasing above 300g/s yet afr stays rich enough (from the meth injection???) to go all the way from 4.5v MAF to peg it at 5.0. Seems to be the 300g/s MAF limitation but I donít know.
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Old 01-29-2021, 07:12 PM   #219
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Anyone know what a 76mm MAF housing is good for in terms of rough g/s or WHP? I am thinking it should be good for around 500g/s?

My 69mm is pegged somewhere between 450-500 g/s I don't know how accurate these readings are right this sec because I suspect my injectors and/or fuel pump may not be keeping up.

There is some weird stuff I am seeing on my ECU, trying to find the hidden "300 g/s" limit, which I am way over, but IDC/IPW is not being calculated right above 300g/s.

So I need to find this 300g/s limit, probably a new AEM 340 fuel pump and a new bigger MAF housing.

I think an AEM 340 on the SC application will be good for around ~475whp.

Last edited by pcampbell; 01-29-2021 at 07:41 PM.
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Old 02-15-2021, 12:28 PM   #220
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Iím thinking if either going Dimemod SD or PMAS MAF. Pmas is more expensive but I think maf for cruising would be nice. The PMAS setup is calibrated sl in theory you just plug in the MAF g/s. Hopefully not a lot of tuning. The setup Iím looking at is good for like 700 g/s. Plenty!
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Old 03-02-2021, 08:37 AM   #221
pcampbell
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Default Vortech supercharger for ~500whp? Si Too big?

Any suggestions on what is going on here - noise occurs around 0:47 , and sounds like launch control timing cut , does NOT sound like any factory limiter such as rev limiter fuel cut which is much slower and softer.

Occurs only at wot or close to it. Iím sort of hoping Iím just dumping too much water meth in and it is killing the spark or quenching combustion.

I originally thought it was the belt slipping and then gripping repeatedly but now Iím not so sure.


I have actually re done the belt setup here to include a HD spring tensioner. So far Iím happy with it , if I can figure out the ďexplosionsĒ under wot!!!!

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Old 03-02-2021, 08:44 AM   #222
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Quote:
Originally Posted by pcampbell View Post
Any suggestions on what is going on here - noise occurs around 0:47 , and sounds like launch control timing cut , does NOT sound like any factory limiter such as rev limiter fuel cut which is much slower and softer.

Occurs only at wot or close to it. Iím sort of hoping Iím just dumping too much water meth in and it is killing the spark or quenching combustion.

I originally thought it was the belt slipping and then gripping repeatedly but now Iím not so sure.

https://youtu.be/SKvDH_j90zQ?t=39

I have actually re done the belt setup here to include a HD spring tensioner. So far Iím happy with it , if I can figure out the ďexplosionsĒ under wot!!!!

https://youtu.be/XjwD5S4C-lw
Were you logging?

Could be anything that causes misfire, not enough timing, injectors maxed, plugs gapped wrong, coil packs dead etc. You've gotta narrow it down 1 by 1
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Old 03-02-2021, 02:24 PM   #223
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Stick a camera on the tensioner. IMO, there is a high risk of the belt touching itself there under heavy load.
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Old 03-03-2021, 07:13 AM   #224
pcampbell
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Default Vortech supercharger for ~500whp? Si Too big?

Quote:
Originally Posted by stevieturbo View Post
Stick a camera on the tensioner. IMO, there is a high risk of the belt touching itself there under heavy load.


I will see if I can figure out how, short of doing it in a dyno. Have you ever heard of belt slip or touching act like this sort of aggressive on/off thing that I get?

Last edited by pcampbell; 03-03-2021 at 07:41 AM.
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Old 03-03-2021, 07:19 AM   #225
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Default Vortech supercharger for ~500whp? Si Too big?

Quote:
Originally Posted by blurred View Post
Were you logging?

Could be anything that causes misfire, not enough timing, injectors maxed, plugs gapped wrong, coil packs dead etc. You've gotta narrow it down 1 by 1

I am logging.

This happens at relatively low load and boost so it shouldnít be injectors or fuel pump. It happens almost right at 2.0 load somewhere in the 4000rpm range every time only when at WOT or very close .

Also if I floor it at say 5000rpm (above where this usually happens), it doesnít happen.

The timing does ramp up aggressively in the range of where the problem happens , because it is usually where water / meth injection starts. As a test of course I tried unplugging water meth controller altogether, no change. So, I may have too much ignition timing change in too short of a time?

I also tried changing the plugs and putting them to 0.20Ē just to see what happens , no change. The fact that if I get past this ďproblem rpm rangeĒ I can make power with more fuel and boost and water/meth makes me think perhaps not ignition component related like plug , wire or coil.

This car uses a single coil pack and I have a spare I can try (it takes 5 minutes to swap ) and also willing to buy a new one if convinced that is the problem. The plug wires are relatively new but again not a huge deal or price to replace if needed.

Last edited by pcampbell; 03-03-2021 at 07:44 AM.
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