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Jan. 23, 2012 9:26 a.m. mguar Reader

Curmudgeon wrote:

loosecannon wrote:

mguar wrote:

In reply to loosecannon: Am I wrong won't longer steering arms equal slower steer rack ratio?

That's definitely a result of the modification and I hope it doesn't become a problem. I won't know if it's a problem until I drive it but according to my computer program, my turning circle is still a reasonable 28.8 feet and my steering ratio is the same as it was before (2.9 turns lock to lock). I think it will be ok but there's still a lot of unknowns with the car.

The steering rack stops are what control the turns lock to lock so no that won't change.

The longer arms will change the total angle the wheel turns in relation to the car (it will be a little less) but probably not enough to massively change the turning circle.

It will definitely change the effort required (it will make it easier to steer).

It will also make the steering a little less twitchy since you will have to turn the steering further to accomplish a given angle.

You said it more accurately. My experience has been to shorten steering arms and move the rack towards the center of pivot.. The result is a faster turn with less hand movement..
(effectively a quicker steering ratio) that's ultra important on really tight twisty tracks like autocrossing tends to be.
Jan. 23, 2012 9:53 a.m. Graefin10 Dork

In reply to loosecannon:

What computer program are you using to help make decisions in your design?
Jan. 23, 2012 1:03 p.m. loosecannon Reader

Graefin10 wrote:

In reply to loosecannon:

What computer program are you using to help make decisions in your design?

Speed-Wiz http://www.speed-wiz.com/
Jan. 30, 2012 5:23 p.m. loosecannon Reader

I took the car for a test drive and after doing some rapid sawing back and forth of the steering wheel, I was not convinced that it would be possible to drive through a slalom without moving my hands on the steering wheel. A cheap and easy fix is adding an Afco 2:1 steering quickener between the steering wheel and rack and pinion steering. It is a beautiful little piece and weighs only 1.8 lbs. Here's a pic of the quickener, it's the blue thing in the middle:

Here's a video of before and after: http://www.youtube.com/watch?v=qjgcCajqJuM
Jan. 30, 2012 6:42 p.m. oldtin SuperDork

Looks like a nice piece! Looks like it will cut down on the flailing. Now you've got power steering by armstrong
Jan. 31, 2012 7:20 a.m. unevolved Dork

I apologize if you've already mentioned this, but how much caster/scrub are you running?
Jan. 31, 2012 12:02 p.m. loosecannon Reader

unevolved wrote:

I apologize if you've already mentioned this, but how much caster/scrub are you running?

No idea on caster and scrub radius is around 2 inches positive. Briget and I drove the car last night and the steering is surprisingly easy. I'm not saying it's easy but it looks like power steering will not be required.
Feb. 13, 2012 7:44 p.m. loosecannon Reader

A bit of background. When the Jag engine let go, a generous friend gave me a recently rebuilt Ford 5.0 that was supposed to have good pistons, cam and ported/polished heads. The problem was that it did not have a roller cam but just an old school flat tappet cam. I found a super cheap but high mileage 1986 5.0 in the paper that had the OEM roller cam in it so I bought that, cleaned it up and stuck it in the car. I had ideas to put a better cam and heads on the 86 5.0 but it turns out to be the one year where Ford used flat top pistons and only 86 heads will work. I decided to pull apart the rebuilt 5.0 out and check out exactly what I have. The bad news is that the heads are a small port, small valve design and reports of being ported/polished were greatly exaggerated. The good news is that the block is set up for a roller cam, the pistons are high quality and have valve reliefs(for big valve heads) and the crosshatch pattern is still in the cylinder walls like it was rebuilt last week. I think I will be hunting for a deal on some good heads and a really aggressive roller cam. Here's some pics of the small ports and the good pistons:
Feb. 14, 2012 10:15 a.m. mguar HalfDork

If you'll put the V12 back in I'll sell you the required repair pieces for less than you'll pay for all that stuff. Or a complete rebuild-able core for $300..
Feb. 14, 2012 4:29 p.m. loosecannon Reader

mguar wrote:

If you'll put the V12 back in I'll sell you the required repair pieces for less than you'll pay for all that stuff. Or a complete rebuild-able core for $300..

You're going to have to give up on the V12, I have already sold off some of the parts and the car has been modified in such a way that putting it back in would be very difficult.
Feb. 14, 2012 6:00 p.m. loosecannon Reader

Update: I have a set of ProComp aluminum heads, Comp Cams steel roller rockers and XE282HR grind roller cam on the way (thanks Phil at www.fasttoys.net). The heads have 2.02/1.6 valves, bigger ports and are 42 lbs less than my iron heads. The cam is pretty wild with .565 in/.574 ex lift, 280 in/292 ex duration. I have no idea what power this combo will make but It should be significantly higher than what I have now. I have been searching Ford forums for what others with these parts have made on the dyno or on the dragstrip and based on that, I am hoping for 275-300 hp at the wheels.
Feb. 14, 2012 10:27 p.m. mguar HalfDork

loosecannon wrote:

Update: I have a set of ProComp aluminum heads, Comp Cams steel roller rockers and XE282HR grind roller cam on the way (thanks Phil at www.fasttoys.net). The heads have 2.02/1.6 valves, bigger ports and are 42 lbs less than my iron heads. The cam is pretty wild with .565 in/.574 ex lift, 280 in/292 ex duration. I have no idea what power this combo will make but It should be significantly higher than what I have now. I have been searching Ford forums for what others with these parts have made on the dyno or on the dragstrip and based on that, I am hoping for 275-300 hp at the wheels.

Find out the flow numbers and lift and duration on the cam plus whatever compression you have and I'll run it through the engine analyzer.
Feb. 15, 2012 11:49 a.m. loosecannon Reader

mguar wrote:

loosecannon wrote:

Update: I have a set of ProComp aluminum heads, Comp Cams steel roller rockers and XE282HR grind roller cam on the way (thanks Phil at www.fasttoys.net). The heads have 2.02/1.6 valves, bigger ports and are 42 lbs less than my iron heads. The cam is pretty wild with .565 in/.574 ex lift, 280 in/292 ex duration. I have no idea what power this combo will make but It should be significantly higher than what I have now. I have been searching Ford forums for what others with these parts have made on the dyno or on the dragstrip and based on that, I am hoping for 275-300 hp at the wheels.

Find out the flow numbers and lift and duration on the cam plus whatever compression you have and I'll run it through the engine analyzer.

Thanks :) I'll give you what I have been able to dig up: Cam specs 282 in/290 ex duration, 232 in/240 ex @ .050, .565 in/.574 ex lift, 112 degree lobe separation. Compression ratio approx 9:1. The heads: INT EX .1-71 55 .2-127 104 .3-178 132 .4-222 165 .5-253 180 .6-279 181 .7-287 182

I am waiting for an e-mail back from Pro-Comp on how much I can shave the heads.
Feb. 15, 2012 4:26 p.m. loosecannon Reader

I just measured things and assuming the heads are actually 60 cc, my compression ratio will be 9.46:1.
Feb. 15, 2012 6:31 p.m. mguar HalfDork
In reply to loosecannon: There are several points I guessed at.. for example I assumed you had 9"x 1.5 primary pipes w/25" collectors (that's typical according to the computer) Actual length and size will help with accuracy.. I'm also assuming you can adjust the fuel air mixture and timing to optimum.. The computer informed me the lifters would pump up (assuming they are hydraulic)
```
Anyway Peak Horsepower is 368 with average of 147.
```
Pk torque is 293 with average at 131

The average isn't really valid right now since I don't know what sort of operating range you're at Right now it's from idle to peak RPM.

If you operate at say 3400-7000 RPM. I can tighten up to those specs and get you more accurate information
Feb. 15, 2012 6:38 p.m. mguar HalfDork

Running it through the analizer program here' the recommendations.. You will need a minimum of 27 #'s/hr injectors.

The stock intake runners are hurting your performance.

Too much cam duration on the intake side.

exhaust headers need to be larger in diameter..
Feb. 15, 2012 6:41 p.m. mguar HalfDork

OOPs peak Horsepower is at 6600 RPM which is past factory redline Peak torque occurs at 6600RPM indicating the engine is over cammed..
Feb. 15, 2012 8:03 p.m. loosecannon Reader

The cam operating range is supposed to be 2500-6500 rpm. The header info is about right, the headers are shorty so some tubes are 6" and some are 17". Not sure about collector length because the headers attach to the 2.5" side pipes. I have a Tweecer so I can put any tune in it and change the redline, too. I have 24 lb/hr injectors and an unported Explorer (GT40) intake. What about the intake runners is hurting me? I am not a stranger to a die grinder and have even had thoughts of building my own upper intake manifold. My idea is to port the lower GT40 manifold then build a box with velocity stacks inside it that will bolt onto it, then have the TB straight out the front instead of the passenger side like it is now. Oh yeh, did you put in the calculator that the engine is a 306 cid?
Feb. 15, 2012 8:19 p.m. Moving_Target New Reader

loosecannon wrote: I have 24 lb/hr injectors and an unported Explorer (GT40) intake. What about the intake runners is hurting me? I am not a stranger to a die grinder and have even had thoughts of building my own upper intake manifold. My idea is to port the lower GT40 manifold then build a box with velocity stacks inside it that will bolt onto it, then have the TB straight out the front instead of the passenger side like it is now. Oh yeh, did you put in the calculator that the engine is a 306 cid?

Porting info for the intake manifold if you're interested. Courtesy of tmoss:

http://www.eectuning.org/forums/viewtopic.php?f=17&t=17146&sid=d396814ba81...
Feb. 15, 2012 8:57 p.m. loosecannon Reader

Moving_Target wrote:

loosecannon wrote: I have 24 lb/hr injectors and an unported Explorer (GT40) intake. What about the intake runners is hurting me? I am not a stranger to a die grinder and have even had thoughts of building my own upper intake manifold. My idea is to port the lower GT40 manifold then build a box with velocity stacks inside it that will bolt onto it, then have the TB straight out the front instead of the passenger side like it is now. Oh yeh, did you put in the calculator that the engine is a 306 cid?

Porting info for the intake manifold if you're interested. Courtesy of tmoss:

http://www.eectuning.org/forums/viewtopic.php?f=17&t=17146&sid=d396814ba81...

That article shows that the GT40 intake is really good when ported but doesn't tell me what I have to do to get it to flow. Does it need to be extrudehoned or can I do it with a die grinder?
Feb. 15, 2012 9:06 p.m. Moving_Target New Reader

Derp. I thought the first link had the porting info in it. Try this one:

http://www.eectuning.org/forums/viewtopic.php?f=17&t=14018
Feb. 16, 2012 12:34 a.m. loosecannon Reader

That is a very helpful article, thanks I will begin porting once my heads arrive
Feb. 16, 2012 8:32 a.m. mguar HalfDork

In reply to loosecannon:

In porting less is more.. Leave the heads alone.. Match the intake to the heads. Shape is everything.. Straight is good. When air goes around corners it's critical that the corners are properly shaped.. Look at mandrel bends and aim to replicate that flow pattern.. The intake length needs to be multiple of the charge length. The plenum works best if it follows the Helmholzt (sp?) resonance theory.

Don't go at it with the idea of if you just open things up it will be better. Carefully match ports. Use go, no-go gauges. (Bent wire works fine) Do the final port work with sanding rolls not cutters.. The level you can control the cutters determines the depth you should switch from cutters to sanding rolls..

Regarding your "headers" Sorry, those are not headers. They are tubular exhaust manifolds.. Proper "headers have a size (length and width) determined by the camshaft. I'll put in the variations you gave me and note how much power you lose.. Reality will be worse since I'll need to assume which tube is which.

Note the firing order and compare when exhaust opens on adjacent cylinders. It could be 90degrees apart or 270, or 180.

The goal of Headers is to time pulses so they work efficiently extracting exhaust gas.. (an object in motion tends to remain in motion)
Feb. 16, 2012 8:42 a.m. mguar HalfDork

OK here's the shocking power difference.. (even I was appalled by the difference) Original horsepower with 9" headers = 368hp Torque = 293 ft.pds.

With your tubular exhaust manifolds = 274hp Torque = 218 ft.pds.

Add 3 hp and 3 ft.pds torque for the .030 overbore.. to 306.13 cu.in
Feb. 16, 2012 9:00 a.m. mguar HalfDork

In reply to mguar: You can gain more useful information if you tell me the operating RPM range. What sort of RPM were you turning the last time you were on track? From what to what..

In a perfect world I could time the length of time you're at say 4200 rpm to 4600rpm compare it to the amount of time you're at other rpm ranges and make suggestions based on actual numbers..

Best way to acquire that information is to have a video camera pointed at the tach and show some of the track. Time under braking doesn't change based on power, Time spent coasting doesn't count either. Only time under acceleration..

The printout comes in a numbers formula and a graph. Since the graph can be a time/Power graph it's simple math to do the calculations.required for actual improvement.. (assuming the car can be made to handle to achieve the time goals)..

At one time I had my favorite tracks plotted in and could make a relatively small change and note a serious improvement in lap times..

3 horsepower gain at the right place could take more than a second off my lap times at Elkart Lake. (4 mile race track with 3 long straights and 14 corners) Whereas a 30 horsepower gain at peak RPM only made a tenth of a second difference.

The old addage horsepower sells motors toque wins races really does apply.. I know you don't want to hear this but that V12 was a torque monster. Print out the power/torque of that and compare it to your Ford.. (wish I could figure out how to send these numbers to you Via E-mail..

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