Fuel Pressure - Page 2

mysweetlx · 08-20-2002, 01:20 PM

I'm currently n/a (gonna be blown or juiced in about 6 months)running 30# injectors w/ Edelbrock Performer heads, TFS track heat intake, 190 # intank pump, etc. I'm adding a AFPR in a few weeks ad want to know what fuel pressure I should put the car at prior to dyno tuning it (just a reasonable # until it gets tuned).....so I can get to the shop.

eatsgmcar · 08-20-2002, 01:22 PM

Yes about 6 more mph in the same day at the track...
i did over 12 run to adjust it. I was adjusting it
even during the elimination (bad idea)

SC

Dark_5.0 · 08-20-2002, 01:22 PM

I was thinking the same thing the 110 mph trap speed is good for low 12's:confused.

Even if he was on street tires hit ET should have been better with a 2.1 60ft.

Very odd.

moponys · 08-20-2002, 01:23 PM

If 38 doesn't work for me, I'm gonna try and raise it up to 60 and see what happens...

I know when I lowered it from 48 to 42, it seemed much slower.

Please let us know the results from the track...

Hyper92GT · 08-20-2002, 01:34 PM

Yes those runs were on street tires BFG KD's very stiff sidewall and the track prep sucked.

60' 2.09
1/8 8.86
mph 80.80
1/4 13.45
mph 110.37mph

I will post my results on Sat. Going Friday night (weather permitting). I expect mph to be down 1-2 due to weight of roll-cage, but et up with new rear suspension (control arms, adj shocks).

Mike

302 LX Eric · 08-20-2002, 01:41 PM

Hyper - going from 80 mph in the 1/8 to 110 in the 1/4 is very impressive. You must be making some serious power. I'm curious, what mods do you have?

With my old 302 heads/cam/intake combo, I would usually go 83 or so in the 1/8 and then 105 or so in the 1/4 - or 22 mph increase. You've got a 30 mph increase!

E

Dark_5.0 · 08-20-2002, 01:47 PM

That looks like the timeslip of someone spraying at the end.

Picking up 30 mph from the 1/8th to the end is unheard of on a car that is only trapping 110.

This whole damn thread is weird

Hyper92GT · 08-20-2002, 01:49 PM

Eric
I wish I could explain it , the car just hauls in 3rd and 4th.
Ususally i trap 83-85mph depending on traction and run 108-110mph consistantly.

I think my car needs more fuel here are some details:
306 sqr. decked block
TRW forged pistions 9:1
Crane cam 270/276 .533/.544
TFS heads, fully ported, manley values hardened rods, dual spring valve
Crane rollers 1:60
70MM T/B
Edlebrock port matched upper/lower
75mm mass air pro-M
pullies/MARCH Ram Air kit
BBK long tubes 1 5/8 with Flowmasters
3;73 gears suspension, cage etc.
MSD 6A, MSD Blaster, 9MM wires etc.
AFPR, 190L/hr pump
Sure some other stuff but you get the idea.

eatsgmcar · 08-20-2002, 03:32 PM

i get only 20.5 mph on the last 1/8 mile...
because of my gear (3.55). Typical mph
gain is around 22 to 24 for a mustang with
3.73 / 4.10 gear (head/intake/cam combo)

If you get 30 mph, well that means your on
street tire, spending more time accelerating
on the last 1/8 because of a lack of traction
on the first 1/8 mile.

SC

302 LX Eric · 08-21-2002, 07:34 AM

I'm running a 3.55 gear and got ~22 mph increase on the big end with my old combo.

Quote:

If you get 30 mph, well that means your on
street tire, spending more time accelerating
on the last 1/8 because of a lack of traction
on the first 1/8 mile.

I agree with this to a point. But, I don't think that if I switched to street tires I would see 8 mph increase. I understand the whole slingshot theory on street tires, but it has its limits.

E

moponys · 08-21-2002, 10:28 AM

Okay guys...

I finally was able to drive my car with the pressure set at 38psi and it ran like crap. When I would rev the engine in neutral, it would backfire every so often. There was no power at WOT. Then when I did what (eatsgmcar) did and set it at 60psi, it ran great. There seemed to be much more power at WOT to the point that when power shifting, the car would get a little squirly when shifting from 1st to 2nd. My car has an aode and usually at the most before, the tires would just chirp but not at 60psi!!!

Talk about weird... I'm gonna have to reverify this by going to the track some time soon...

Thanks,

SlowGT · 08-21-2002, 11:45 AM

60# sure seems high. But I guess I'll be giving it a try if I ever get my car back from Moroso.

I'm new to the power shifting game. Never wanted to do it cause of the rebuild cost. But since I started rebuilding my own, I practice the power shift every chance I get. I'm on my 3rd set of 2nd & 3rd synchros in as many months, but they only cost $12 each. Then figure 3-4 hrs putting them in. Much cheaper than any tranny shop I've ever seen.

Anyway, my question was: How do you power shift an automatic? I thought you could hold your foot to the floor and let the tranny do the rest. I'm not very familiar with ATs. Actually, I don't know anything about ATs other than they give you a lot more consistency than a MT.

Thanks.

moponys · 08-21-2002, 12:06 PM

I'm not sure if it's really called power shifting but it seems to give me faster times at the track...

I manually shift my aode from with o/d off at around 5800 from 1st-2nd-d. I have a Transgo shift kit in the tranny but it doesn't always shift fast enough on its own...

Some other guys with aods told me that shifting manually would give me faster times...

Now my times aren't that fast but I've never really had my car running in top condition yet...

AJSTANG · 08-21-2002, 07:53 PM

Moponys: I run the same heads and cam but with the Cobra intake. My best setting was at 18 degrees timing /45 psi. I initially set the car up at 14 degrees/39 psi but it was sluggish. The additonal timing and fuel pressure was worth 3 tenths and 3 mph at the drag strip with the same 60 ft and density altitude.

Pkrwud: Your incorrect about the horsepower assumption. Actually the combo is worth more than 350 considering he has the TFS street intake which is better than the Cobra. I could trap 108 mph in my 3500 pound conv. with this set up.

PKRWUD · 08-21-2002, 09:27 PM

Quote:

Originally posted by AJSTANG
Pkrwud: Your incorrect about the horsepower assumption. Actually the combo is worth more than 350 considering he has the TFS street intake which is better than the Cobra.

If you say so. I'm not seeing it. Got a dyno sheet?

08-20-2002, 01:20 PM	#21
mysweetlx Registered Member Join Date: Apr 2002 Location: New York Posts: 248	I'm currently n/a (gonna be blown or juiced in about 6 months)running 30# injectors w/ Edelbrock Performer heads, TFS track heat intake, 190 # intank pump, etc. I'm adding a AFPR in a few weeks ad want to know what fuel pressure I should put the car at prior to dyno tuning it (just a reasonable # until it gets tuned).....so I can get to the shop. __________________ Damn this thing's fast!

08-20-2002, 01:22 PM	#23
Dark_5.0 Registered Member Join Date: Apr 2001 Location: Staging lane Posts: 4,337	I was thinking the same thing the 110 mph trap speed is good for low 12's:confused. Even if he was on street tires hit ET should have been better with a 2.1 60ft. Very odd. __________________ 92' LX-Big brakes, Lots and lots of suspension, GT40X heads, Ported cobra intake, stock cam, Vortech SC trim. 00' Lightning-Stock 88'CRX-13 second ego killer

08-20-2002, 01:23 PM	#24
moponys Registered Member Join Date: May 2001 Location: Antioch, CA 94521 Posts: 181	If 38 doesn't work for me, I'm gonna try and raise it up to 60 and see what happens... I know when I lowered it from 48 to 42, it seemed much slower. Please let us know the results from the track... __________________ N/A 94 GT vert w/aode...12.19 @110 w1.67 60' Some bolt ons

08-20-2002, 01:34 PM	#25
Hyper92GT slow like mud Join Date: Mar 2000 Location: toronto Posts: 180	Yes those runs were on street tires BFG KD's very stiff sidewall and the track prep sucked. 60' 2.09 1/8 8.86 mph 80.80 1/4 13.45 mph 110.37mph I will post my results on Sat. Going Friday night (weather permitting). I expect mph to be down 1-2 due to weight of roll-cage, but et up with new rear suspension (control arms, adj shocks). Mike __________________ 1992 DECH GT Not stock, still slow.

08-20-2002, 01:41 PM	#26
302 LX Eric or '331 LX Eric' Join Date: Jan 1999 Location: Columbus, Ohio Posts: 2,142	Hyper - going from 80 mph in the 1/8 to 110 in the 1/4 is very impressive. You must be making some serious power. I'm curious, what mods do you have? With my old 302 heads/cam/intake combo, I would usually go 83 or so in the 1/8 and then 105 or so in the 1/4 - or 22 mph increase. You've got a 30 mph increase! E __________________ 1991 5.0 LX Coupe - 40,750 miles 331 cu. in. / Tremec 3550 / BFG Drag Radials 12.22 @ 114.31 mph - w/1.89 60'

08-20-2002, 01:22 PM	#22
eatsgmcar Registered Member Join Date: Jul 2002 Location: Pont Rouge, Quebec, Canada Posts: 45	Yes about 6 more mph in the same day at the track... i did over 12 run to adjust it. I was adjusting it even during the elimination (bad idea) SC

08-20-2002, 01:47 PM	#27
Dark_5.0 Registered Member Join Date: Apr 2001 Location: Staging lane Posts: 4,337	That looks like the timeslip of someone spraying at the end. Picking up 30 mph from the 1/8th to the end is unheard of on a car that is only trapping 110. This whole damn thread is weird __________________ 92' LX-Big brakes, Lots and lots of suspension, GT40X heads, Ported cobra intake, stock cam, Vortech SC trim. 00' Lightning-Stock 88'CRX-13 second ego killer

08-20-2002, 01:49 PM	#28
Hyper92GT slow like mud Join Date: Mar 2000 Location: toronto Posts: 180	Eric I wish I could explain it , the car just hauls in 3rd and 4th. Ususally i trap 83-85mph depending on traction and run 108-110mph consistantly. I think my car needs more fuel here are some details: 306 sqr. decked block TRW forged pistions 9:1 Crane cam 270/276 .533/.544 TFS heads, fully ported, manley values hardened rods, dual spring valve Crane rollers 1:60 70MM T/B Edlebrock port matched upper/lower 75mm mass air pro-M pullies/MARCH Ram Air kit BBK long tubes 1 5/8 with Flowmasters 3;73 gears suspension, cage etc. MSD 6A, MSD Blaster, 9MM wires etc. AFPR, 190L/hr pump Sure some other stuff but you get the idea. __________________ 1992 DECH GT Not stock, still slow.

08-20-2002, 03:32 PM	#29
eatsgmcar Registered Member Join Date: Jul 2002 Location: Pont Rouge, Quebec, Canada Posts: 45	i get only 20.5 mph on the last 1/8 mile... because of my gear (3.55). Typical mph gain is around 22 to 24 for a mustang with 3.73 / 4.10 gear (head/intake/cam combo) If you get 30 mph, well that means your on street tire, spending more time accelerating on the last 1/8 because of a lack of traction on the first 1/8 mile. SC

08-21-2002, 10:28 AM	#31
moponys Registered Member Join Date: May 2001 Location: Antioch, CA 94521 Posts: 181	Okay guys... I finally was able to drive my car with the pressure set at 38psi and it ran like crap. When I would rev the engine in neutral, it would backfire every so often. There was no power at WOT. Then when I did what (eatsgmcar) did and set it at 60psi, it ran great. There seemed to be much more power at WOT to the point that when power shifting, the car would get a little squirly when shifting from 1st to 2nd. My car has an aode and usually at the most before, the tires would just chirp but not at 60psi!!! Talk about weird... I'm gonna have to reverify this by going to the track some time soon... Thanks, __________________ N/A 94 GT vert w/aode...12.19 @110 w1.67 60' Some bolt ons

08-21-2002, 11:45 AM	#32
SlowGT Registered Member Join Date: Jun 1999 Location: Columbia Co, PA Posts: 303	60# sure seems high. But I guess I'll be giving it a try if I ever get my car back from Moroso. I'm new to the power shifting game. Never wanted to do it cause of the rebuild cost. But since I started rebuilding my own, I practice the power shift every chance I get. I'm on my 3rd set of 2nd & 3rd synchros in as many months, but they only cost $12 each. Then figure 3-4 hrs putting them in. Much cheaper than any tranny shop I've ever seen. Anyway, my question was: How do you power shift an automatic? I thought you could hold your foot to the floor and let the tranny do the rest. I'm not very familiar with ATs. Actually, I don't know anything about ATs other than they give you a lot more consistency than a MT. Thanks. __________________ Old Slow GT New Slow GT--> under construction Latest Addition: 95 Cobra R, #73, bone stock, ~6100 miles.

08-21-2002, 12:06 PM	#33
moponys Registered Member Join Date: May 2001 Location: Antioch, CA 94521 Posts: 181	I'm not sure if it's really called power shifting but it seems to give me faster times at the track... I manually shift my aode from with o/d off at around 5800 from 1st-2nd-d. I have a Transgo shift kit in the tranny but it doesn't always shift fast enough on its own... Some other guys with aods told me that shifting manually would give me faster times... Now my times aren't that fast but I've never really had my car running in top condition yet... __________________ N/A 94 GT vert w/aode...12.19 @110 w1.67 60' Some bolt ons

08-21-2002, 07:53 PM	#34
AJSTANG Registered Member Join Date: Nov 2000 Location: Maryland Posts: 123	Moponys: I run the same heads and cam but with the Cobra intake. My best setting was at 18 degrees timing /45 psi. I initially set the car up at 14 degrees/39 psi but it was sluggish. The additonal timing and fuel pressure was worth 3 tenths and 3 mph at the drag strip with the same 60 ft and density altitude. Pkrwud: Your incorrect about the horsepower assumption. Actually the combo is worth more than 350 considering he has the TFS street intake which is better than the Cobra. I could trap 108 mph in my 3500 pound conv. with this set up. __________________ '91 Notchback TFS Heads(stage 2), B-451 Cam, V2-Si trim, TKO-600

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