408 Inspection Time - Page 4

fast83 · 04-12-2008, 10:39 AM

wow very nice answer and now I completely understand the situation and why. I do agree 302 is not ment for a truck not near enough torque to get it rolling. WOW IRS now that is insane but wickedly custom nice job. Is there a reason for wanting to go with an AOD obviously you want overdrive for fuel ecomomy but that would be kinda like me wanting an FMX in my truck? I definatly have to say that is a very nice torque non-curve so to speak I am sure not many people can hang light to light. I respect your friends alot as well for having your back, just think some may be quick on the trigger as my intention were not to knock you but to understand you.

Bad as L · 04-12-2008, 06:02 PM

Quote:

Originally Posted by svt2785

You have a number of issues going on here.
Start with the cylinder marks and bearings. Both show clear signs that you are running to much timing. A 408 will need around 28 to 30 total timing max due to the stroke, rod length and that small of cam. A 408 piston moves pretty slowly at the top and bottom of the stroke. I don't know what your static compression is but assuming it is over 9.5 to 1 you will have an lot of dynamic compression with a pretty early intake closing afforded by the short duration of the intake lobe. That's why your torque numbers are high at a low RPM range. The bearings are getting pounded because you have to much timing lead. Some scuffing is pretty normal but excessive timing is increasing the side loading. the proof is in the rod bearings

Heads: The guide wear is from improper valve train geometry. You either have to long or to short a pushrod. Go to a site like Miller Engineering to find out how to properly set the rocker arms. AFR 185's are notorious for poor rocker positioning. You will need a set of Isky adjustable guide plates to get it right or you can expect to continue to have guide problems. Your Machinist should have picked up this problem in an instant and if he is any good he should know how to correct the problem.

Felpro intake gaskets are junk. plain and simple. Try to find a set of Victors which are graphite over a steel core.

I don't mean to nit pick but a long stroke short rod motor has a quicker moving piston with less dwell time at the top of the stroke (TDC) and a relatively slower moving piston with longer dwell time at the bottom of the stroke (BDC). In other words a 408 has a shorter piston dwell time and a quicker moving piston at TDC than a stock 351 does but a longer dwell time and a slower moving piston at BDC.

The timing the motor needs will be dictated by the combustion chamber shape/cylinder head (among other things) more so than piston speed.

fast83 · 04-12-2008, 06:33 PM

I am not sure of the 408 configuration but I am pretty sure that atleast on a 393 stroker there are 2 ways to get that stroke a stock 5.9 rod and a 6.2 rod if this is also true for a 408 then both of you guys can be correct

but seriously is this correct with the 408

Sportruk · 04-12-2008, 08:38 PM

I have the Eagle rotating assembly with 6.2" I-Beams. It's been my belief that a stroked engine is going to give you a longer dwell time at TDC and BDC over stock. The longer rod improves the rod ratio and helps to reduce the side loading on the cylinder wall. The dwell timing at TDB and BDC is the same. A long stroke will have increased piston speeds due to the longer rotational travel of the increased arc radius, but at the same time, it reaches the end of the stroke sooner, making it stay there longer.
svt2785, thanks for pointing me in the direction of Miller Egnineering. Excellent tech info on Mid-Lift design theory. It further confirms my thoughts on the geometery. There was a write up, years ago, in the Mustang Performance Handbook that desribed the same principle but didn't go into depth, other than say you should be at this point at 50% of lift. By the looks of some pictures when I got the engine from the builder, the push rods are to short.
Unforunaitely, without a way to adjust the pushrod fulcrum point, it's impossible to get all the benifits of Mid-Lift design. I can only concentrate on the valve side of the rocker, to minumize guide wear.
Early on, I did have detonation issues and have brought the timing down in the 32* total range. I will further work on the timing when I get it back running and retune it.
My static comp ratio is 9.67/1, with a dynamic ratio of 8.4/1. From what I have read, I am nearing the upper end of dynamic CR range on 91 octane.
Thanks for the help.

svt2785 · 04-12-2008, 09:26 PM

Quote:

Originally Posted by Bad as L

I don't mean to nit pick but a long stroke short rod motor has a quicker moving piston with less dwell time at the top of the stroke (TDC) and a relatively slower moving piston with longer dwell time at the bottom of the stroke (BDC). In other words a 408 has a shorter piston dwell time and a quicker moving piston at TDC than a stock 351 does but a longer dwell time and a slower moving piston at BDC.

The timing the motor needs will be dictated by the combustion chamber shape/cylinder head (among other things) more so than piston speed.

Bad as L,

Nit picking is OK. You are correct of course regarding the piston dwell at the top of the stroke ( I need to edit my own posts more carefully). However the low rod ratio of this combination means the piston moves away from BDC slowly trapping a higher % of cylinder volume. Regardless of combustion chamber shape if the intake valve is closing pretty early, which his cam will, the result will be some pretty high dynamic compression. Unless his static CR is under 9:5. Bottom line he's beating rod bearings and needs to either back up his timing or find some higher octane fuel. All the theory means nothing. Believe the results. The dynamic compression developed is directly related to the intake closing and it is going to be the most significant factor in determining the timing and fuel requirements IMO. Thanks for the come back.

fast83 · 04-14-2008, 04:33 PM

well what I have always understood is it would depend on if it is a long rod stroke or a short rod stroke mathamaticlly is perfectly logical would have different rod speed and dwell time one would be higher rpm motor one would be lower rpm motor. does anyone have any further info on this?

Sportruk · 04-22-2008, 11:35 PM

Update time. Things are going slow, but I'm taking the time to further understand the rocker geometery. I modelled the valve train in Solidworks and found that by increasing the push rod .100", I have increased lift by .0065" and brought the rocker to proper geometery. The roller tip rolls a total of .025" across the valve tip.

I rolled out my old 351 and found that it had the .100" longer rods I needed and they are quality hardened rods with pressed in ends instead of the welded balls. The guide plates were also .010" less in width to improve the rocker centering on the valve tip.
The dial indicator confirmed the modelling exactly.

The cam card shows lift at the lifter as .321" and at the valve as .512" with a 1.6/1 rocker, but actual measuring is .5342", so it's better than originally thought.
I got the bottom end sealed up and the heads are on.
I sent some parts out for ceramic coating. The top of the intake is ceramic coated and the bottom side has an insulating coating done.

The finish wasn't as shiny as I hoped, but Mothers Billet polish brings it up beautifully. I'm only half done so far.

The exhaust is also ceramic coated and the inside is done with a different insulating coating. It will keep the exterior from loosing it's brightness and keep the heat in the pipes. Yes, I even did the cat, but Shhh, it's a camouflaged straight pipe.

I ordered a new dogbone, so I hope to have the engine put together on the weekend, then redo the tranny lines before it goes back in.

tbonemcniel · 04-23-2008, 12:05 AM

looks awesome shawn!

madramper · 04-23-2008, 07:19 AM

Lookin' good!

fast83 · 04-23-2008, 11:14 AM

very nice I like the way the intake is comeing for you

95Blitz · 04-24-2008, 02:55 AM

Quote:

Originally Posted by Sportruk

Yes, I even did the cat, but Shhh, it's a camouflaged straight pipe.

.

hehehe I like it.

Sportruk · 05-02-2008, 11:28 PM

Well, I haven't gotten very far. I mucked up one of the lifters and had to order a new one.
I got the intake finished and just finishing up polishing the tensioner. I just put the lifters in and ready to seal it up. Then change the tranny lines and drop it back in.
Note to anyone buying a set of stock 5.0/5.8 roller lifters. Don't get the from any of the aftermarket cam companies. They are cheapest from the local auto parts supplier. You can only buy them in 4 packs and I only needed one, so I wasn't going to Ford at $35 each x4. Comp cams was 3 weeks delivery. I ordered Mellings lifters at the supplier for $13 each x4. They are identical to the Comp Cams lifter. That's Canadian pricing, so cheaper for you guys.
Anyways, the other thing wasting my time was the buying of an '08 FX2 and an '08 Mustang V6 Pony for the wife. Ordered them last Saturday and still waiting. It's driving me nuts. Took a couple days to bring them in from another dealer and their prep guy has been sick. Looks like next Monday now.
The Stang is Vista Blue and charcoal interior.
This will be mine with 20" painted wheels.

tbonemcniel · 05-04-2008, 04:46 PM

that's a good lookin dd for ya. sellin ur old '97-03 bodystyle truck i assume?

Sportruk · 05-04-2008, 05:01 PM

Ya, the silver '97 goes tomorrow. I've had it for 9 years. There nothing really wrong with it, just time for a new one.

Sportruk · 05-20-2008, 11:32 PM

Well, it's alive. Got it finished up on Monday. I still haven't hit the road, but it sounds good.
I hope to have it tuned up for next Sunday. The local Mustang club is having a dyno day and I want to see how it's doing since the fuel system upgrade last year and the changes I recently made.
While putting it back together, it got new Taylor wires, MSD cap, rotor and Blaster TFI coil. The starter was upgraded to a '94 stocker.It sounds so much better while starting. The old one was having a hard time starting the engine when it was hot.
In the Bling department, I polished up the tensioner, made a new fitting for the PCV valve and repolished the existing aluminum.
When it came time to start it, I preprimed the oil pump, dropped in the dizzy, eyeballed the rotor to cap and bolted it down.
It cranked about 3 turns and fired right up. The timing was only a few degrees retarded and I set it at 12*. A/F ratio was still bang on from last year.
I just need to cleanout the box, as it gathered lots of junk from the winter.
Hopefully it's not raining tomorrow and it can roll out to meet the new pair, out in the driveway.

04-14-2008, 04:33 PM	#51 (permalink)
fast83 Registered User Join Date: Sep 2007 Location: bryan, Texas Posts: 268 View this user's gallery iTrader: 0 / 0%	well what I have always understood is it would depend on if it is a long rod stroke or a short rod stroke mathamaticlly is perfectly logical would have different rod speed and dwell time one would be higher rpm motor one would be lower rpm motor. does anyone have any further info on this? __________________ this is all you will see

04-23-2008, 12:05 AM	#53 (permalink)
tbonemcniel Oil Field Trash Join Date: Mar 2005 Location: Bryan, TX Posts: 736 View this user's gallery iTrader: 0 / 0%	looks awesome shawn! __________________ 1993 F-150 Lightning - Street Toy 2003 F-150 Harley-Davidson - Cruiser/Tow Pig 1978 Bronco - Off Road Toy 2008 F-250 - Work Truck/Daily Driver

04-23-2008, 11:14 AM	#55 (permalink)
fast83 Registered User Join Date: Sep 2007 Location: bryan, Texas Posts: 268 View this user's gallery iTrader: 0 / 0%	very nice I like the way the intake is comeing for you __________________ this is all you will see

05-04-2008, 04:46 PM	#58 (permalink)
tbonemcniel Oil Field Trash Join Date: Mar 2005 Location: Bryan, TX Posts: 736 View this user's gallery iTrader: 0 / 0%	that's a good lookin dd for ya. sellin ur old '97-03 bodystyle truck i assume? __________________ 1993 F-150 Lightning - Street Toy 2003 F-150 Harley-Davidson - Cruiser/Tow Pig 1978 Bronco - Off Road Toy 2008 F-250 - Work Truck/Daily Driver

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04-12-2008, 10:39 AM	#46 (permalink)
fast83 Registered User Join Date: Sep 2007 Location: bryan, Texas Posts: 268 View this user's gallery iTrader: 0 / 0%	wow very nice answer and now I completely understand the situation and why. I do agree 302 is not ment for a truck not near enough torque to get it rolling. WOW IRS now that is insane but wickedly custom nice job. Is there a reason for wanting to go with an AOD obviously you want overdrive for fuel ecomomy but that would be kinda like me wanting an FMX in my truck? I definatly have to say that is a very nice torque non-curve so to speak I am sure not many people can hang light to light. I respect your friends alot as well for having your back, just think some may be quick on the trigger as my intention were not to knock you but to understand you.

04-12-2008, 06:33 PM	#48 (permalink)
fast83 Registered User Join Date: Sep 2007 Location: bryan, Texas Posts: 268 View this user's gallery iTrader: 0 / 0%	I am not sure of the 408 configuration but I am pretty sure that atleast on a 393 stroker there are 2 ways to get that stroke a stock 5.9 rod and a 6.2 rod if this is also true for a 408 then both of you guys can be correct but seriously is this correct with the 408

04-12-2008, 08:38 PM	#49 (permalink)
Sportruk Registered User Join Date: Mar 2006 Location: Brampton, Ont, Canada Posts: 2,054 View this user's gallery iTrader: 0 / 0%	I have the Eagle rotating assembly with 6.2" I-Beams. It's been my belief that a stroked engine is going to give you a longer dwell time at TDC and BDC over stock. The longer rod improves the rod ratio and helps to reduce the side loading on the cylinder wall. The dwell timing at TDB and BDC is the same. A long stroke will have increased piston speeds due to the longer rotational travel of the increased arc radius, but at the same time, it reaches the end of the stroke sooner, making it stay there longer. svt2785, thanks for pointing me in the direction of Miller Egnineering. Excellent tech info on Mid-Lift design theory. It further confirms my thoughts on the geometery. There was a write up, years ago, in the Mustang Performance Handbook that desribed the same principle but didn't go into depth, other than say you should be at this point at 50% of lift. By the looks of some pictures when I got the engine from the builder, the push rods are to short. Unforunaitely, without a way to adjust the pushrod fulcrum point, it's impossible to get all the benifits of Mid-Lift design. I can only concentrate on the valve side of the rocker, to minumize guide wear. Early on, I did have detonation issues and have brought the timing down in the 32* total range. I will further work on the timing when I get it back running and retune it. My static comp ratio is 9.67/1, with a dynamic ratio of 8.4/1. From what I have read, I am nearing the upper end of dynamic CR range on 91 octane. Thanks for the help.

04-22-2008, 11:35 PM	#52 (permalink)
Sportruk Registered User Join Date: Mar 2006 Location: Brampton, Ont, Canada Posts: 2,054 View this user's gallery iTrader: 0 / 0%	Update time. Things are going slow, but I'm taking the time to further understand the rocker geometery. I modelled the valve train in Solidworks and found that by increasing the push rod .100", I have increased lift by .0065" and brought the rocker to proper geometery. The roller tip rolls a total of .025" across the valve tip. I rolled out my old 351 and found that it had the .100" longer rods I needed and they are quality hardened rods with pressed in ends instead of the welded balls. The guide plates were also .010" less in width to improve the rocker centering on the valve tip. The dial indicator confirmed the modelling exactly. The cam card shows lift at the lifter as .321" and at the valve as .512" with a 1.6/1 rocker, but actual measuring is .5342", so it's better than originally thought. I got the bottom end sealed up and the heads are on. I sent some parts out for ceramic coating. The top of the intake is ceramic coated and the bottom side has an insulating coating done. The finish wasn't as shiny as I hoped, but Mothers Billet polish brings it up beautifully. I'm only half done so far. The exhaust is also ceramic coated and the inside is done with a different insulating coating. It will keep the exterior from loosing it's brightness and keep the heat in the pipes. Yes, I even did the cat, but Shhh, it's a camouflaged straight pipe. I ordered a new dogbone, so I hope to have the engine put together on the weekend, then redo the tranny lines before it goes back in.

04-23-2008, 07:19 AM	#54 (permalink)
madramper Supporting Vendor Paid Member Join Date: Jun 2002 Location: Alloway, NJ Posts: 11,493 NLOC member #: 937 View this user's gallery iTrader: 43 / 100%	Lookin' good!

05-02-2008, 11:28 PM	#57 (permalink)
Sportruk Registered User Join Date: Mar 2006 Location: Brampton, Ont, Canada Posts: 2,054 View this user's gallery iTrader: 0 / 0%	Well, I haven't gotten very far. I mucked up one of the lifters and had to order a new one. I got the intake finished and just finishing up polishing the tensioner. I just put the lifters in and ready to seal it up. Then change the tranny lines and drop it back in. Note to anyone buying a set of stock 5.0/5.8 roller lifters. Don't get the from any of the aftermarket cam companies. They are cheapest from the local auto parts supplier. You can only buy them in 4 packs and I only needed one, so I wasn't going to Ford at $35 each x4. Comp cams was 3 weeks delivery. I ordered Mellings lifters at the supplier for $13 each x4. They are identical to the Comp Cams lifter. That's Canadian pricing, so cheaper for you guys. Anyways, the other thing wasting my time was the buying of an '08 FX2 and an '08 Mustang V6 Pony for the wife. Ordered them last Saturday and still waiting. It's driving me nuts. Took a couple days to bring them in from another dealer and their prep guy has been sick. Looks like next Monday now. The Stang is Vista Blue and charcoal interior. This will be mine with 20" painted wheels.

05-04-2008, 05:01 PM	#59 (permalink)
Sportruk Registered User Join Date: Mar 2006 Location: Brampton, Ont, Canada Posts: 2,054 View this user's gallery iTrader: 0 / 0%	Ya, the silver '97 goes tomorrow. I've had it for 9 years. There nothing really wrong with it, just time for a new one.

05-20-2008, 11:32 PM	#60 (permalink)
Sportruk Registered User Join Date: Mar 2006 Location: Brampton, Ont, Canada Posts: 2,054 View this user's gallery iTrader: 0 / 0%	Well, it's alive. Got it finished up on Monday. I still haven't hit the road, but it sounds good. I hope to have it tuned up for next Sunday. The local Mustang club is having a dyno day and I want to see how it's doing since the fuel system upgrade last year and the changes I recently made. While putting it back together, it got new Taylor wires, MSD cap, rotor and Blaster TFI coil. The starter was upgraded to a '94 stocker.It sounds so much better while starting. The old one was having a hard time starting the engine when it was hot. In the Bling department, I polished up the tensioner, made a new fitting for the PCV valve and repolished the existing aluminum. When it came time to start it, I preprimed the oil pump, dropped in the dizzy, eyeballed the rotor to cap and bolted it down. It cranked about 3 turns and fired right up. The timing was only a few degrees retarded and I set it at 12*. A/F ratio was still bang on from last year. I just need to cleanout the box, as it gathered lots of junk from the winter. Hopefully it's not raining tomorrow and it can roll out to meet the new pair, out in the driveway.