Are claimed AFPR increases valid?
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Are claimed AFPR increases valid?
This is from the FAQ page on this site:
It states a 58 ft lb increase with just this $50 part. The table disagrees and reads a 77.5 ft lb maximum increase. This information seems a bit suspect. Where did these #'s come from and can anyone confirm them? I am going to bolt one of these up, along with a host of other goodies, the weekend after next when the roc comes out of storage. What type of real world increase can I expect to feel?
Q: What fuel pressure setting will give me the best performance?
The stock setting is 42 PSI. Much track testing has showed that any type of increase will greatly benefit both horse power and torque. Here's some dyno testing on a stock 350 motor which substantiates those claims:
42 PSI (stock) 46 PSI 50 PSI
RPM Torq HP Torq/diff HP/diff Torq/diff HP/diff
------------------------------------------------------------------------
2250 237.7 101.8 254.9/17.2 109.2/ 7.4 275.0/37.3 117.8/16.0
2500 241.7 115.1 262.1/20.4 124.8/ 9.7 283.3/41.6 134.9/19.8
2750 241.5 126.5 275.2/33.7 144.1/17.6 297.0/55.5 155.5/29.0
3000 237.1 135.4 278.2/41.1 158.9/23.5 305.5/68.4 174.5/39.1
3250 233.8 144.7 278.9/45.1 172.6/27.9 311.3/77.5 192.6/47.9
3500 241.0 160.6 278.2/37.2 185.4/24.8 309.5/68.5 206.3/45.7
3750 246.6 176.1 283.4/36.8 202.4/26.8 303.3/56.7 216.6/40.5
4000 250.4 190.7 278.3/27.9 212.0/21.3 298.0/47.6 227.0/36.3
4250 251.6 203.6 272.5/20.9 220.5/16.9 289.1/37.5 233.9/30.3
4500 253.5 217.2 257.3/ 4.2 220.5/ 3.3 277.0/23.5 237.3/20.1
4750 245.0 221.6 242.1/-2.9 219.0/-2.6 266.4/21.4 240.9/19.3
5000 227.6 216.7 225.0/-1.4 214.2/-2.5 237.8/10.2 226.4/ 9.7
It shows that by increasing the fuel pressure to 50 PSI, results in maximum torque increase of 58 ft-lbs (along with a much flatter torque curve) and a maximum horse power increase of 19 HP over stock. 46 PSI also provides a noticable increase which should work well for day-to-day street driving. An adjustable fuel pressure regulator (see Chap 5.2) is required to increase the fuel pressure.
The stock setting is 42 PSI. Much track testing has showed that any type of increase will greatly benefit both horse power and torque. Here's some dyno testing on a stock 350 motor which substantiates those claims:
42 PSI (stock) 46 PSI 50 PSI
RPM Torq HP Torq/diff HP/diff Torq/diff HP/diff
------------------------------------------------------------------------
2250 237.7 101.8 254.9/17.2 109.2/ 7.4 275.0/37.3 117.8/16.0
2500 241.7 115.1 262.1/20.4 124.8/ 9.7 283.3/41.6 134.9/19.8
2750 241.5 126.5 275.2/33.7 144.1/17.6 297.0/55.5 155.5/29.0
3000 237.1 135.4 278.2/41.1 158.9/23.5 305.5/68.4 174.5/39.1
3250 233.8 144.7 278.9/45.1 172.6/27.9 311.3/77.5 192.6/47.9
3500 241.0 160.6 278.2/37.2 185.4/24.8 309.5/68.5 206.3/45.7
3750 246.6 176.1 283.4/36.8 202.4/26.8 303.3/56.7 216.6/40.5
4000 250.4 190.7 278.3/27.9 212.0/21.3 298.0/47.6 227.0/36.3
4250 251.6 203.6 272.5/20.9 220.5/16.9 289.1/37.5 233.9/30.3
4500 253.5 217.2 257.3/ 4.2 220.5/ 3.3 277.0/23.5 237.3/20.1
4750 245.0 221.6 242.1/-2.9 219.0/-2.6 266.4/21.4 240.9/19.3
5000 227.6 216.7 225.0/-1.4 214.2/-2.5 237.8/10.2 226.4/ 9.7
It shows that by increasing the fuel pressure to 50 PSI, results in maximum torque increase of 58 ft-lbs (along with a much flatter torque curve) and a maximum horse power increase of 19 HP over stock. 46 PSI also provides a noticable increase which should work well for day-to-day street driving. An adjustable fuel pressure regulator (see Chap 5.2) is required to increase the fuel pressure.
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Car: 1986 pontiac TA
Engine: 360 HSR
Transmission: 700r4 3300 yank converter
Axle/Gears: 3.27 9 bolt
Re: Are claimed AFPR increases valid?
Originally posted by Dustin Mustangs
This is from the FAQ page on this site:
It states a 58 ft lb increase with just this $50 part. The table disagrees and reads a 77.5 ft lb maximum increase. This information seems a bit suspect. Where did these #'s come from and can anyone confirm them? I am going to bolt one of these up, along with a host of other goodies, the weekend after next when the roc comes out of storage. What type of real world increase can I expect to feel?
This is from the FAQ page on this site:
It states a 58 ft lb increase with just this $50 part. The table disagrees and reads a 77.5 ft lb maximum increase. This information seems a bit suspect. Where did these #'s come from and can anyone confirm them? I am going to bolt one of these up, along with a host of other goodies, the weekend after next when the roc comes out of storage. What type of real world increase can I expect to feel?
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From: Manassas VA
Car: 04 GTO
Engine: LS1
Transmission: M12 T56
An AFPR is simply a rough tuning tool. Nothing more, nothing less. Could you potentially pick up a couple tenths w/ one. Yes if you know what you are doing and actually TnT rather than put it on, bump it up and forget it.
Re: Re: Are claimed AFPR increases valid?
Originally posted by mrr23
depends on engine. my 350 with the 19lbs/hr injectors i had set at 52psi. at the dyno day i just went to i needed to bring it down to 43psi and i picked up 5 hp off that.
depends on engine. my 350 with the 19lbs/hr injectors i had set at 52psi. at the dyno day i just went to i needed to bring it down to 43psi and i picked up 5 hp off that.
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Re: Are claimed AFPR increases valid?
Originally posted by Dustin Mustangs
This is from the FAQ page on this site:
It states a 58 ft lb increase with just this $50 part. The table disagrees and reads a 77.5 ft lb maximum increase. This information seems a bit suspect. Where did these #'s come from and can anyone confirm them? I am going to bolt one of these up, along with a host of other goodies, the weekend after next when the roc comes out of storage. What type of real world increase can I expect to feel?
This is from the FAQ page on this site:
It states a 58 ft lb increase with just this $50 part. The table disagrees and reads a 77.5 ft lb maximum increase. This information seems a bit suspect. Where did these #'s come from and can anyone confirm them? I am going to bolt one of these up, along with a host of other goodies, the weekend after next when the roc comes out of storage. What type of real world increase can I expect to feel?
that the 58 ft lbs is a peak TQ value difference. Look at the blue highlighed areas below.
Stock#s @4500RPM peak TQ 253.5 TQ 217.2 HP
46psi/FP @3250RPM peak TQ 311.3/77.5 TQ 192.6/47.9 HP
The difference between 253.5 TQ and 311.3 TQ is 57.8 or rounded of to 58 ft lb.
Yes, this is from TPIS's Insiders Hints book.
I personally did'nt notice a 60 Ft Lb of torque difference. Maybe 20ft lbs of TQ at best. It seems that this was another attempt by TPIS to sell parts with exaggerated claims. -I would love to go from my stock HP @ 230 to 249 and go from 320 TQ to 380 TQ. That would be the best bang for the buck mod out there if it were true.
https://www.thirdgen.org/newdesign/faq/thirdgen.shtml
<FONT COLOR="red"><pre>
42 PSI (stock) 46 PSI 50 PSI
RPM Torq HP Torq/diff HP/diff Torq/diff HP/diff
------------------------------------------------------------------------
2250 237.7 101.8 254.9/17.2 109.2/ 7.4 275.0/37.3 117.8/16.0
2500 241.7 115.1 262.1/20.4 124.8/ 9.7 283.3/41.6 134.9/19.8
2750 241.5 126.5 275.2/33.7 144.1/17.6 297.0/55.5 155.5/29.0
3000 237.1 135.4 278.2/41.1 158.9/23.5 305.5/68.4 174.5/39.1
<font color="#0000FF">3250</font> 233.8 144.7 278.9/45.1 172.6/27.9 <font color="#0000FF">311.3/77.5 192.6/47.9</font>
3500 241.0 160.6 278.2/37.2 185.4/24.8 309.5/68.5 206.3/45.7
3750 246.6 176.1 283.4/36.8 202.4/26.8 303.3/56.7 216.6/40.5
4000 250.4 190.7 278.3/27.9 212.0/21.3 298.0/47.6 227.0/36.3
4250 251.6 203.6 272.5/20.9 220.5/16.9 289.1/37.5 233.9/30.3
<font color="#0000FF">4500 253.5 217.2</font> 257.3/ 4.2 220.5/ 3.3 277.0/23.5 237.3/20.1
4750 245.0 221.6 242.1/-2.9 219.0/-2.6 266.4/21.4 240.9/19.3
5000 227.6 216.7 225.0/-1.4 214.2/-2.5 237.8/10.2 226.4/ 9.7
</pre></font>
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Last edited by whiteroc; Mar 19, 2002 at 02:31 PM.
Supreme Member
Joined: Oct 2001
Posts: 1,392
Likes: 4
From: orlando, fl usa
Car: 1986 pontiac TA
Engine: 360 HSR
Transmission: 700r4 3300 yank converter
Axle/Gears: 3.27 9 bolt
Re: Re: Are claimed AFPR increases valid?
Originally posted by mrr23
depends on engine. my 350 with the 19lbs/hr injectors i had set at 52psi. at the dyno day i just went to i needed to bring it down to 43psi and i picked up 5 hp off that.
depends on engine. my 350 with the 19lbs/hr injectors i had set at 52psi. at the dyno day i just went to i needed to bring it down to 43psi and i picked up 5 hp off that.
It's all dependent on how far off you are too begin with. Will it replace a properly tuned chip, NO. But it can help you out in between chips if you don't burn your own. Mrr23 picked up 15 ftlbs, I picked up 10 hp and 15 ftlbs at the peaks. There were ploaces I picked up 40 ftlbs, but the initial a/f was way off. So basically if your tuneing is perfect, you will see no gains. But if your off, or the original regulator is off, then yes you can see huge gains.
Supreme Member
Joined: Oct 2001
Posts: 1,392
Likes: 4
From: orlando, fl usa
Car: 1986 pontiac TA
Engine: 360 HSR
Transmission: 700r4 3300 yank converter
Axle/Gears: 3.27 9 bolt
Re: Re: Are claimed AFPR increases valid?
Originally posted by mrr23
depends on engine. my 350 with the 19lbs/hr injectors i had set at 52psi. at the dyno day i just went to i needed to bring it down to 43psi and i picked up 5 hp off that.
depends on engine. my 350 with the 19lbs/hr injectors i had set at 52psi. at the dyno day i just went to i needed to bring it down to 43psi and i picked up 5 hp off that.
well had to bring it back up to 49psi. either the wideband o2 was reading wrong or the tech was wrong about threadings. took it to www.vincihiperformance.com they have a dynojet and was was wanting to compare the differences. i ran my codes and got lean exhaust. made 5 runs and figured out 49 psi was best.
www.fl-thirdgen.org/mrr23-dynosheet.html
here are the differences.
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