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Why isn't my car fast?


Guest FordMotherFocus

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Guest FordMotherFocus

This is what Im running:

74? camaro 350 c.i. short block rebuild

Including 9.5 flat top pistons

Crower solid roller camshaft .567 lift 288 dur

Crane gold 1.65 roller rockers

Crower solid roller lifters

Trick flow pushrods

DartII heads 2.05/1.60,springs rated to .700 lift

Port matched to intake

Brodix HV1 pro bracket intake ported with heads

Fluid damper SFI balancer

Stock water pump with 160 degree thermo

MSD 6al ignition box

Holley Street Avenger 770

Summit oil pan and melling pump

Billet valve covers / Edelbrock pro-flo

Accell 8.8 mm wires/ plugs

Sanderson QP1000 Headers

Desktop dyno software rates this combo between 464 and 513 horsepower

 

Took my car to the track for the first time and all I could get was a 9.317 at 74.618 (1/8th). I guess with those times I'm pushin around 200whp. Whats wrong? I know nothing about tuning engines. How much does a good tune job usually cost? Could I really get over 400hp with this combo?

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Its sounds like you bought Longs Z. If you still have a 700r4, you should check what kind of gearing you have. Check your differential gears, see what you have, your gears maybe set up for maximum fuel economy. Then check your fuel and timing, is it too rich or too lean. It's like what Phantom said it depends on your gearing too.

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Desktop Dyno doesnt factor in speed nor does it take into account the car; such as the gearing as the previous replies have suggested. Quick question: What rpm did desktop dyno give for peak power/hp? Were you at the peak rpm when you ran the 1/8mile track?

 

From the desriptions of your build it indicates to me you probably have an engine that doesnt really come into power till after the 4k rpm area.

 

If you are running the stock rear end and stock wheels/tires then your 75mph 1/8mile run has not allowed your car to get up on rpm's which is where your cam, intake, cyl.heads need to be.

 

If you dont know your Static Comp. Ratio nor your Dynamic Comp. Ratio then I would merely ask you, "How do you feel your engine is running"?

 

What are the rpm's at the end of your 1/8mile run -vs- the rpm's when you have reached 100mph; and can you tell a difference from the sound of the engine as it reaches the end of the 1/8mile -vs- when you have reached a WOT 100mph?

 

If you feel the engine is strong at the end of a hard accelerating WOT 100mph run....then as the other guys suggested: your problem is most likely your gearing (differential gear ratio, wheels & tire size).

 

Your engine is built for above 4500rpm's and not below it. If you want a strong running car in the 1/8mile track then you will have to alter you gearing, or you could downsize your cyl.heads, intake manifold, camshaft and maybe the carb also.

 

Airflow charachteristics determine how the "ENGINE" will run, whereas "GEARING" determines how your car will run for any particular given track. The two should compliment each other for their specific required intentions.

 

Kevin,

(Yea,Still an Inliner)

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This sounds very familiar! I had the same problem! If you want to run this set up you will need to be running a 3 to 4k stall converter. Also you need gears 3.90 or 4.11 on stock r200 rear end. That is if you are running a Datsun rear end. My set up did not come on until 3200/3500 and really pulled around 4k and up. I personaly got sick of lack of power around town, bad idle, etc..

 

I went from a 244 duration cam at .50 to a 224/230 duration cam at .50 also swapped my victor jr. for a Weiand stealth dual plane intake. Those two changes did it for me.

 

I now have a 2k to 6k set up and love it. I run a 2300/2500 stall and 3.54 gears with 26" tall tires. I may go 3.90's.

 

The launch is powerful now.

 

Remember if you stay with that combo wind that puppy up to 7k to 7.5k before shifting. It sounds like it was made for it!

 

Mike

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Hey Ford Focus I just noticed you live in the Metroplex. There are alot of us V8Zer's in the area. Give me a call sometime and maybe we can meet at the races or something.

 

I have several V8 conversion friends locally,some Datsun and Healy conversions. We just talked about going to the track to settle bragging rights. Of course if Daniel brings his supercharged 383 sbc I do believe we know the outcome of the fastest Z but maybe I could turn his fuel pressure way down. nono.gif

 

Mike

972-422-0858

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If that is Long's motor (ala MYRON), then zfan is correct: it was made to scream. The power will be in the top end. And, like zfan said, swapping out the cam and intake will give it better lower end characteristics, but it begs the question as to what the purpose of the car is going to be: street or strip? Or both?

 

Davy

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Guest Anonymous

Since the subject is on cams and gearing. There is a new Summit cam "package" On E Bay. 204/214 degree @.50 with lift .420/.442 ..112 degree lobe seperation. The current price ($124.00) for all the cam and misc. gear about rivals Summits catalog price($170.00) which now disinterests me..This cam grind is the Edelbrock Performer grind.I have the Edelbrock Performer package in another engine with no complaints about idle and performance. What do you fellows think of this mild grind: 214/224 degree @.50 with lift .442/.465 ...112 lobe seperation.I was thinking this might help "Right Now I drive A Focus" to alter his "circle track engine" . Great parts but at a very high RPM. I want a street engine that goes like hell between stop lights.

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Guest FordMotherFocus

My car has the stock rearend(r200) in and I think it is 3.54. Also stock wheels and tire size. I feel my car is running real poorly. Right now the dash is out so I have no idea what rpm I was shifting at and the msd has a 6k plug in it. As for the desktop dyno, this is just what long told me, so I don't know. I want a car that will run 12s but still pull an Ls1 on the street. I would love to meet up with some local guys and see everyones setup. I moved to Corinth two days ago(1 minute from Denton) ten minutes from North Texas Dragway. Good place to meet and race.

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RightNowIDriveAFordFocus

first thing youve got to do is get that engine running correctly, here read and learn.

 

http://www.bob2000.com/carb.htm

 

http://www.nastyz28.com/perftune.html

 

http://www.centuryperformance.com/vacuum.htm

 

http://www.bgsoflex.com/holley.html

 

http://www.shockley.net/holley-jets.asp

 

after you get it running correctly in its presant form, you can assess what needs to change

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A tach is a 'must' of you want to get the most out of the performance of the car. Not knowing what rpm you are shifting at is almost like not using headlights at night: you have an idea of where you are going, but you don't get there as efficiently. If you are relatively new to performance V8's or even to the particular cam grind in that car, then just shifting by the sound the motor makes without a tach is a mistake. See if you can get a tach hooked up, then go from there. The ideas about the cam grinds above are pretty good, especially regarding streetability. The last one mentioned (Summit K-1103 grind) is a '350 hp' cam.: the torque starts down low, which is great for the street, and the hp tops about 5500 to 6000 rpm if I remember correctly. You engine combo can handle a lot more cam, but if it is streetability you are looking for, that particular grind is a decent one for cheap that will do very well at the stop light grand prix. Now, there are other cam manufacturers, like Crane and Comp Cams, that make great cams--you can call their tech lines and discuss what you have and what you want it to do, and they can give you some great suggestions. Just food for thought.

 

Davy

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Guest FordMotherFocus

Thanks for the great info guys. The only reason I am at the track without a tach is I have new car fever. I guess I really need to figure out what I really want my car for: drag, street, or parking lots and cones?

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Guest Anonymous

You didn't mention if those times were made burning the tires the whole time or if it just hooked and thats what it really has HP wise. I'm not good enough with quarter mile performance numbers to know that, if I recall MPH is a indication of HP particularly if its later in the track, but if the 60' time which I guess is the key to drag racing I gather is not super good either through loss of traction or low HP then your times will be disappointing. It sounds like you have the hardware to run a good time, though. As mentioned get a tach, find out the characteristics of your motor and what the cam likes RPM wise and if it is still building power when you were shifting. Good luck with it, it sounds like it has alot of potential.

 

Regards,

 

Lone

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if thats longs with the myron motor, that car is capable of way better than that, just gotta practice, that car has some firepower, but you gotta be able to put it down by learning how to get it down, mess wit it, im sure that car is faster than that.

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  • 2 weeks later...

Hey Guys, Kevin brought the Z over to my house last night. We ran a compression test and got 160 to 165 lbs from the five cylinders we tested.

Man is it hard to get to those angle plugs with those Sanderson headers.

 

There are a few problems with the car,first if Myron could get cam specs it would really help. Cam does not seem that radical.

 

The car has no tach or speedo so this hurts but he had it dynoed and it fell off after 4500 rpm's. This seems odd, the dyno shop changed jets for him and got an increase in power but is real far off from acceptable.

 

The carb needs work but most of all i think his HEI needs serious attention. Could be bad coil or advance etc. is sticking but car seems to have a serious miss to it.

 

If anything the carb maybe a little bit lean but not bad. We drove car to my favorite get into it and bang gears spot. It ran what I would guess to be 14 even 15 second 1/4 mile performance.

He really needes a tach as I said earlier. The car obviously has 12 second potential.

 

The car has great potential but needs some ignition work. I recommended he go to Compitition Machine of Plano and see Mickey..He built my engine and Im very happy with it.

 

Kevin's a good guy and has a good car like the rest of us he will learn as he goes on with his project. Kevin if you read this go to Mickey and tell him Mike with the purple v8 Z sent you.

 

If you want I can meet you over there.

 

Good luck and if you need help holler!

sorry we ran out of daylight.

 

Mike

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Kevin, If they try to talk you into a dual plane intake, I have an almost new Edelbrock RPM Air-Gap dual plane I will let go for 100 bucks, thats half the price of a new one.

 

Mike

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Kevin,

 

Talked to my friends about your problem and most think it could be your HEI. It is stock isnt it?

My friends said that stock HEI dies at 4500 rpm's real loss of power plus could be that built in coil that is causing that miserable miss in there.

 

They agreed your build should be hot in that car and if possible do not change a thing motor wise.

 

They said 12's should be easy with your set up.

 

Cheers Mike

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