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Discussion Starter #1
The car is a 66 mustang with a C-4 and 3:55 gears. I have had the engine rebuilt several times and it still ends up being a dog out of the hole and over all the car is not that impressive on performance.
I have taken the engine out to give it one last try but this time we are putting a T-5 behind it. Listed below are the components I have and I would like any suggestions or comments that people have.
- Holley 600CFM Mechanical Secondary
- Performer RPM Intake
- Stock Ported 289 Heads
- Flat top pistons with 4 valve reliefs
- Current Camshaft is a Comp Cam 270H (the cam may be my problem)
- HIPO cast iron manifolds - unfortunately these have to stay
- 2 inch stainless dual exhaust with an H
pipe.

If anyone has a proven receipt, I would appreciate some advice. My thoughts were to raise the compression to 10:1 along with changing the cam to maybe a 268 or 260 from Comp Cam or go with a roller.
Thanks for any help.
 

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On 2002-02-21 13:48, strobels wrote:
The car is a 66 mustang with a C-4 and 3:55 gears. I have had the engine rebuilt several times and it still ends up being a dog out of the hole and over all the car is not that impressive on performance.
What mods have you done to the C-4?

What kind of times have you ran, and what do you want to run???
 

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headers headers headers. i know you said the exhaust manifolds have to stay, but that and a T5 and its a totally different car.
 

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Did you go with bigger valves in those heads? If not, those tiny exhaust valves combined with the restrictive exhaust manifolds is hurtin' ya bad!
 

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The dog out of the hole syndrome is caused by a mismatch between the rpms the motor wants to run at and the rpms your transmission, gears and tires are allowing it to run at. When you come out of the hole if you are not at your torque peak when you leave the motor will just fall flat on its face. Essentially, all 289/302's are dogs out of the hole, LOL. Thats why you want 4.56 or lower gears and a launch rpm between 4500 and 5000.
 

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Discussion Starter #6
Thanks for all the input and I agree that the little 289 does not have alot of torque on the bottom end.
As far as the exhaust valves go, I do believe we went to larger intake and exhaust. What we should have done is bought a set of World Product heads instead of sticky money into the 289 heads but that is water under the bridge.
The C-4 was completely redone with a reverse valve body along with putting a TCI 2400 or 2500 rpm stall, but when you tried launching the car, the converter would engage at a lower RPM probably due to poor torque curve of the cam. The C-4 is out and up for sale. The sad thing is that the car was not driven over a couple hundred miles a year because it was such a dog.
I am thinking about putting Crane Cams roller conversion in the motor.
 

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Get your T-5 put in and get a set of headers and 2 1/2" exhaust. You'll notice quite a difference when installing the five speed. When I went from a auto to 4 speed, I couldn't believe the difference. It was like a whole new car. Felt like I had 100 more horses.
 

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The RIGHT port work on the heads is good... Either that, or get an aftermarket set. A set of AFR 165's sure would look nice on the engine.

If you want to keep the 289 heads, I specialize in porting them. I did my heads. I charge $350 for porting only if you're interested. Properly set up, they can work really well with your combination. Money back if you're not satisfied.

As for the cam.... A Comp Cams XE262H would be nice. It has an intake duration about like the 268 High Energy, with a little extra exhaust duration. The split pattern will be nice with the manifolds and street exhaust.

As for the exhaust system, you need more. The stainless is indeed pretty, but the 2" system is choking the engine. I'd like to see 2.5" on the car. You DEFINITELY need a good set of tailpipes... and the only ones worth having are Flowmaster MANDREL bent units. Muffler shops cannot do mandrel bending. The pipe gets crushed anytime they make a bend... and the tight bends required to make tailpipes crushes the pipes down to nothing. The Flowmaster units aren't crushed at all, and measure a free-flowing 2.5" in diameter. They are only $99 from summit, and are the best hundred bucks you'll spend on the car. Be careful with muffler length. There isn't much room under an early mustang, so long mufflers will put that first tailpipe bend too close to the axle. Edelbrock RPM mufflers sound really good, and are what I've got on my car.

You'll like the stickshift. It makes the car feel MUCH quicker.


GET THE FLOWMASTER TAILPIPES!!!!

Good Luck!

_________________
Mike Burch, 66 mustang real street
302 4-speed 289 heads, 10.63 @ 129.3
http://www.geocities.com/carbedstangs/cmml_mburch.html
http://www.fortunecity.com/silverstone/healey/367

<font size=-1>[ This Message was edited by: n2omike on 2/22/02 8:21am ]</font>
 

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dont be so quick to abandon that combo.
Project 11.99, before it was what is is, had a similar combo... ported 289 heads, stock 289 bottom end (miserable 8.7:1 compression)
similar cam, rpm intake, and 650 double pumper.

however with a t5 and open 3.55 gears. Car went 12.80's on McRearys, and ran very well on the street.

To me you problem is probably,well definately the cast manifolds, to begin with. you simply have more air going in that you can expel.

Secondly the T5 will help immension, as you will go to a 3.35 first gear from what a 2.4 somthing on the C4.


Why must you have those manifolds? A Try Y or short header will actually make the exhaust sounds less harsh and offer no problems for clearance.
 

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Discussion Starter #10
Thanks again for all the information, you guys are truely helpful.

The car is actually my fathers car and for what ever reason, he must have a thing against headers. He likes the cast iron manifolds since at the time, they were hard to come by.
He wants to stay with the current exhaust set up since he has some $$$$ in not only the manifolds but also the stainless exhaust system. Unless we could sell the current system, it would be hard to swallow the thought of putting on a whole new exhaust system.
Thanks again.

Scott
 

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One more thing to do is check your dist. advance curve. a slow curve,(fairly common on that motor) will very much dog that combo out.
 

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Discussion Starter #13
I will be selling the Tranny and Convertor, most likely seperate. I will let you know when I decide to get rid of it. I will let you know very soon.

Scott
 

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That is a very basic combo that should run well. I used the 351W firing order 270 Magnum Comp Cam in my fairly heavy '68 Falcon wagon I had in the 80s. Ran 13.20s with .030" over reman short block with 4 valve relief flat top pistons, stock reman '69 351W heads(unported), Rhoads lifters(added low end torque), Performer 289 intake, 650DP, 1 1/2" long tube headers and glasspacks bolted to the collectors(yuck!), 3.55 geared 8" traction lock rear, stock C-4 with stock converter(Rhoads really helped it launch once installed), Duraspark ignition, and regular 60 series 14" radials(don't remember the exact size). Before I put the Rhoads lifters in, it was a dog out of the hole but after installing them, it came alive at launch. The 650 DP helped the launch too compared to the 600 vacuum secondary POS which ran well but never offered the response or power at launch compared to the 650 DP. Quick advance with lite springs and 1" open spacer under the carb. It weighed 3770 without me in it which was weighed at Little River Academy Raceway south of Temple, TX. Got great gas milage and was about as mild as you can get and still have respectable ETs. Unfortunately I used the stock retainers and locks and eventually dropped a valve trashing the whole engine but your combo should be running much stronger than you say it is. If your pistons are sitting in the cylinder .020-.050" at TDC, then that might be your problem for most cast flat top pistons are short on compression height so you actually lose a great deal of power compared to the same compression with a dish at "0" deck. Make sure that cam isn't installed 4 degrees retarded and for god sakes, use Rhoads lifters with that tight converter. You'll be surprised at the difference it makes with launching.
 
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