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Discussion Starter #1
weather was pretty damn hot.

Combo is trickflow heads, trickflow R intake w/ 1" spacer
Buddy rawls custom cam, 1-3/4" longtubes, 3" exhaust

pro-m 80mm plastic mass air, 30# injecters, stock A9L ECU, 70mm T.B., AFM power pipe

Underdrive pullies, no power steering, no smog stuff etc)

TCI Streetfighter AOD(manual etc) 3800 stall, 3.73 gears, 26" tall et drag (not spinning)

Race weight 2975 with me in the car (2780 with me out !)

60' 1.759
330 5.170
1/8 8.026 @ 85.34
1000 10.547
1/4 12.738 @ 103.21

Issues :

Had a fan belt problem, it wants to walk forward and off the pullies

Car seemes to launch pretty hard, and goes completly straight...
I was only shifting around 5800 rpm

Fuel pressure set to 32psi vacuum off as per mustangworks's fuel system analyzer

timing at 18 degrees base with a mixture of 87 and 94 gas (no detonation)

Car has some sort of fuel problem, it DUMPS fuel into the cylinders during starting, and I suspect during nomral running too. Someone said it could be air temp sensor on the lower manifold ? If it goes screwy the car will think its running at -40 degrees and dump fuel in.

Car seems to fall on its face in third gear (third is 1:1 its an AOD remember)

Can someone compare my times to other heads/cam/intake cars in 1/8th mile ? My goals are high 11's at around 114 mph

I'm only gaining 17mph in the last 1/2 of a track. 12.7 @ 103 seems to me that it's running pretty strong off the line and then dies in the last 1/2...

Car is not running out of fuel as im running an a1000 pump and a fuel cell with -8 line
 

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Hmm, have you gone through the basics? Compression test, verify all cylinders are firing with no busted plugs....all injectors fully seated....your tune sounds very close to what it will like, maybe a tad more fuel pressure but it should still run much faster. The shifts should probably be higher as you know, but thats not going to give you 10mph. Have you ran codes on it? Easy enough to throw a new act/ect on there and see if it helps you out. Humidity and heat can knock you back 5mph if its really bad, but there still seems to be an issue here.
 

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I would play with the fuel pressure also at least put it to stock specs. Are you sure it isn't detonating? It could be and your not hearing it. that would kill your top end power(plus your motor). On a average most cars pick up at least 20 mph in the second half of the 1/4 mile. My aod car runs a much slower ET than you with a higher MPH. It is much heavier with way less stall. I have a 1/8 mile speed of 83 to a trap speeed of 105. I would bump the fuel pressure and run some high octane fuel Just to see if it helps.
 

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Discussion Starter #4
I havent had a chance to pull the plugs yet. planning on doing that tommarow since i store the car at my parents house.

Hopefully it wasnt detonating but hey you never know... exhaust was way too damn loud so I couldn't hear much.


I figure i'm losing power above 4000 rpm from first gear onwards, even the 1/8th mile trap speeds seems a bit low.

I tried running the fuel PSI at 40 psi and the car chokes out and dies when idling as soon as it warms up.
 

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jonathan said:
Issues :

Had a fan belt problem, it wants to walk forward and off the pullies your belt tensioner may be going bad, usually an idler pulley throws the belt off the car, other times the tensioner does

Car seemes to launch pretty hard, and goes completly straight...
I was only shifting around 5800 rpmWhy is that an issue?

Fuel pressure set to 32psi vacuum off as per mustangworks's fuel system analyzer that seems fine to me

timing at 18 degrees base with a mixture of 87 and 94 gas (no detonation) thats alot of timing try 14* inital

Car has some sort of fuel problem, it DUMPS fuel into the cylinders during starting, and I suspect during nomral running too. Someone said it could be air temp sensor on the lower manifold ? If it goes screwy the car will think its running at -40 degrees and dump fuel in. Our cars with our sefi systems do not have cold start injectors, when we start the ecciv fattens up the mixture like a carbs choke thermostat would close the air horn. are your pipes black? the CPU may be in defualt mode due to maybe an air temp sensor or a bad 02(more usual), are the o2s stock?

Car seems to fall on its face in third gear (third is 1:1 its an AOD remember) what gears do you have, is that a lockup convertor did you get a sheet from the manufacturer saying its usual slippage percent?

If you are planning to run 11s you should get some useful guage like an egt sensor
 

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I have the same weight as you basically, and turn a 12.0 @ 114 quarter currently.

in the 1/8 I'm usually around 7.7 @ 89.x, probably needs to be a 7.6x @90.x to squeak the 11.x I've been looking for.


that intake is too big for a 302, swap it for a performer rpm.


edit: I run my 30# injectors at 37-38 PSI vac-off, spun 318 rwhp raw at that value.


try more fuel (in 2 psi increments)
 

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O2 sensors have nothing to do with start up period. Air charge sensors are major in start up. Doesn't matter what his converter slip is, or lock up or non lock up his MPH is way off.
 

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2stangs69-91 said:
O2 sensors have nothing to do with start up period. Air charge sensors are major in start up. Doesn't matter what his converter slip is, or lock up or non lock up his MPH is way off.
you need to reread my post. did i say anything about 02s doing anything with startup? slippage, bad heat and a pig rich car will give you a low mph.

93chp is right on with the intake i just saw that. unless your cam is around 310 duration and .590 lift and you have 11.5:1 that intake is hurting you.

BTW were you staging deep?
 

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so slipage bad heat and pig rich wouldn't effect the ET and 1/8 mile times? I do agree with the manifold choice. but I seriously doubt that intake would effect MPH since that is what it is all about. It would hurt low end and 60 foot times alot more.
 

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2stangs69-91 said:
so slipage bad heat and pig rich wouldn't effect the ET and 1/8 mile times? I do agree with the manifold choice. but I seriously doubt that intake would effect MPH since that is what it is all about. It would hurt low end and 60 foot times alot more.
No I think he should be running 7.70s. The problem might be with his 3.73s, when it goes into d it might be out of its powerband, which would be short with a mis-matched intake, Any track based high rpm streetcar with aod should be running 4.10s to 4.56s. Yet he did say that he was shifting @ 5800, which really means the intake needs to be changed
 

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its not a high rpm set-up. it was not intended to be. the intake flow and cross section (although large) was part of the equation for the valve events.

I say, keep tuning and learning the set-up. seat time is important. with a 3800 stall the set-up ought to be laying 60' times in the mid 1.60's, but the effective gearing and tire dia may be preventing that somewhat.

tuning, learning a launch technique, honing in on the best shift rpms, are going to take it on down in the times. it could respond favorably to a little higher shift.

The total advance is most likely going to end up being in 30-34 degree range. so whatever that equates to in the initial setting, will be a good starting point.

also, remember, the rpm stuff was matched to the 26" tire. the intent was to trade off for the 28's when running the bottle. this was an attempt to get the most into the set-up without restricting the set-up to the higher rpms when using nitrous and hurting the low rpm response when running without the bottle.

thats because with the low rpm limit you wanted and the 3.73's, it was going to have to take a change in tire diameter when running in the 10's with large nitrous system.

you are effectively running a ratio with 3.73's. this will be effecting the launch.

The set-up was spec'd at being right on the edge. because the rpm capability needed when you start throwing the bottle at is going to be so much different than non-nitrous, that attempting to cam it based on those rpms was going to hurt the n/a response badly. thats where the gear change or rather tire change for the NOS blast were going to be needed.

I stick to my guns and say that things are changing from the initial requirements on the cam. it will do what you want, but you have to work it within the criteria that was originally planned.

in additon you have be tuned pretty well, and you have to learn where the set-up wants to be driven.

Buddy
 

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I just read my post and I goofed. I meant to say I don't agree with the manifold choice. If the entire setup was ment to be a NOS deal then I can understand. Regardless of all that a 17 mph pickup in the second half is pretty weak so something in the tune is way off. I am sticking to my possible detonation and low fuel pressure statement. Even if adjusting your fuel pressure up causes a rich idle condition it is only going to be that way untill the computer learns to lean it down as much as possible.
 

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2stangs69-91 said:
[BEven if adjusting your fuel pressure up causes a rich idle condition it is only going to be that way untill the computer learns to lean it down as much as possible. [/B]
only true at part throttle positions were the EEC-IV uses it's adaptive strategy.

At, WOT, it uses a stock table and adjusting the fuel pressure has a direct effect on air fuel ratio. I've seen it myself countless times on the dyno, driven the car 100's of miles, and repeated the same gains at the track.

You're 100% right about non-WOT operation, though.


Thinking about the TFS-R intake, I still say too big but this combo has much bigger problems than that right now--- missing 10+ mph is not going to come from an intake swap.

Firing order? burnt plug wire? compression/leakdown? got spark?
 

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Ya, o2's aren't a wot thing, they only effect the mixture at part throttle.
 

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well your combo is a high reving setup..so far i can see a few things..with a 302 those heads and that intake you should be shifting at 7k..what was the shift point according to your cam maker..
32psi is too low for fuel..you should allways try to keep it around the 40psi range..if 40 psi is too much then you need a progremable ECU or to get the right size injectors
 

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Discussion Starter #16
I havent pulled the plugs yet but im 99% sure all plugs are firing right.

I have faith in the combo as does buddy and i wont be changing intakes.

The ACT could be bad... the car doesnt idle well at 40 psi but i havent tried flooring it. I'm going to be swapping ECU and the air temp sensor tommarow. Also I have to install some sort of idler pully because I'm only running crank, waterpump and alternator... and the belt doesnt wrap around the waterpump enough, so it's slipping.

Need to get some 26" slicks... The ones I used were borrowed, I need to buy some new ones.

As for the lack of torque with a TF-R intake, that isnt the problem... As soon as I punch it the car pulls hard... To further attest to this, how can I be running 12.7's at only 103mph unless the car was pulling really hard at the start, and going weak at the top end... If the TF-R was the problem you'd think I would be gaining mph near the end.

Buddies cam so far has been REALLY good, so good infact that at 18 degrees base timing the cam sounds stock hehe. at 10 degrees base with idle set around 700rpm it has a bit of a lump to it, but nowhere enar what an e303 cam has.

Keep in mind also I only got 1 clean run. The valve body is semi manual, meaning it will shift on its own in d, but when I do the 1 - d - 1 shuffle, it will shift exactly when I tell it to... unfortunatly I keep forgetting to pull it back to 1, so its shifting from 1 to 2 to 3 all in about 20 feet.

The one clean run I got (12.7) I was concentrating on operating the shifter so much that I wasnt watching the rpms. So even though there is still definatly something up with the motor, a lot of it is just seat time. I havent been in my mustang down the strip since fall of 2000. :p

Anyways thank for the help guys im gonna put a snap on scanner on the car tommarow and see exactly whats going on.
 

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no way on the converter issue of to much slipage.
 

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why do you say that? look at his 1/8 mile mph compared to his 1/4

judging by the 1/8 et and MPH the car should run 12.50s @ 108 in the 1/4

is the convertor a non lock up? my guess is that it is
 

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Discussion Starter #20
correct, converter is a non lockup, but the guy who built it builds converters for 7 second mustangs, and he custom built it for me... also the stall speed was recomended by buddy rawls.
 
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