88 XR7 6.8L 420ci V10

Topic: 88 XR7 6.8L 420ci V10 (Read 6450 times) previous topic - next topic

88 XR7 6.8L 420ci V10

June 12, 2007, 12:21:18 PM

I want the FPP V10 Ford offers in their Power Product line. It is 31" wide compared to the 302 which is 22". It is rear sump so I think it will clear. The hood clearance however will be a problem. The only reason why the engine is soo tall is the stupid intake manifold. Unfortunaly not enough people have theses engines so finding aftermarket manifolds is impossible. Since I am going for a sleeper, the hood will have to be custom. What kind of hood options are we looking at? Currently I pulled the latch and put in hood pins in front. I kept the hinges on back as hood is kinda heavy:hick: Since the v10 is a modular engine, I can only bore it out to .03 over. Bore/stroke is 3.55x4.17 which is 415ci. I can bore out the piston to 3.58 and increase to 420ci. I am afraid of increasing rod length as the this block has deep side skirts for durability. With that being said, I am looking at forced induction or additives. Nitrous seems easiest, though a turbo sounds nice. Stock v10 eats about 450cfm, so it might be smarter to start with 2 turbos with a mild tune. First thing's first though, I want to rework the stock heads and get them breathing better. I could swap out for the newer v10 heads which have 2 intake ports and 1 exhaust. Not sure if it would be worth it or not, but if the head was designed to flow 2 valves worth of air, most likely it was designed to flow more air internally also which means more cavity space and less amount of metal to grind. So I would have head start. As for the radiator, the v10 is only 1" longer than the 302v8! So there is plenty of room for a massive 4-6core radiator. The transmission will fit any of the modular family (4.6/5.4/6.

so that means, i can put a 2003-2004 ford cobra t56 tremec 6speed transmission. This one is an expensive one. Used on ebay looks at about 1k-1.5k. Oh by the way, the reason I decided with v10 instead of the 460 is because the 460 weighs about 750lbs as the v10 was only 640lbs. Yet it puts out more power. Stock 302 is in mid 400's so I will need to beef up the suspension a little more. New springs/shocks from a buddies fast body he is going to sell me for 100 bucks! Let me know if I forget stuff or what you think about this project!
thanks

88 XR7 6.8L 420ci V10

Reply #1 – June 12, 2007, 02:42:52 PM

The V10 will not even come close to fitting under a stock, or even a cowl hood. MM&FF magazine had an article on one in a Mustang, and even with a 4" cowl the guy had to cut the hood to make it fit. Don't forget you'll have to use hydraulic power brakes as well, as the wide Modular won't clear a vacuum booster.

Sounds like an interesting project, but there are easier ways to make big-block type power - a stock 460 might weigh 750 pounds, but I'd bet one with alloy heads and intake would be lighter than that V10 and make more power to boot, plus it would be far cheaper to build and install. A 427 stoker Windsor would be even lighter...

88 XR7 6.8L 420ci V10

Reply #2 – June 12, 2007, 03:54:50 PM

I had one of those V10's. It was a DOOOOOOOGGGG. That POS couldn't get out of it's own way let alone tow. Stick a 5.4 4V or a 4.6 3V in there instead, they both make more power even in n/a form.

88 XR7 6.8L 420ci V10

Reply #3 – June 12, 2007, 03:57:59 PM

if its one inch longer then a 302 then those must be some small ass pistions!

88 XR7 6.8L 420ci V10

Reply #4 – June 12, 2007, 04:23:10 PM

408 CI will be enough of engine if you just buy all the good performance parts to go with it.

88 XR7 6.8L 420ci V10

Reply #5 – June 12, 2007, 05:17:05 PM

yikes...as sick of an idea it is im not sure its the best way to go. you could have a custom sheetmetal intake made up. i know someone who managed to fit a 5.4 DOHC under the stock hood of a 04 mustang gt. i have no idea how much taller physically the V10 is. no doubt the truck intake is out. as far as i know the V10 is basically the 5.4 stretched out. its not much longer and should be the same width. Carm is correct in that you would need to convert to hydrobost but that isnt to bad realy. that or manual brakes. i would think that would lick grundle on the street but some guys do it. apparently you allready realize you need to get into the bottom end of it with forged inturnals if you want some serious boost with reliability. thats gonna put a hurtin on the wallet. i know how much it costs to forge a 4.6 DOHC and im not looking foward to it. likely you are gonna want some custum cams for it as the stockers are geared for towing. god bless you if you can afford it. i agree with aerobird. id look into a 5.4 DOHC. id run a custom intake. perhaps the ausi boss 290 intake on a built up aluminum navigator block. give boss330 raceing a call. al papito is the freaking man whith this stuff....who knows, he may know a thing or 2 about the V10 as well. not trying to dog you ar sway you. id love to see something like that done up. reguardless man. good luck.

Forged Internals

Reply #6 – June 13, 2007, 11:21:54 AM

The crank is stock forged with split pin journals. It should hold up to 600hp safely. I want a v10 over v8 because of the way it winds up. When you look at the power dyno's of these engines, the represent peak and continuous. These engines don't wind up the same every time like v6/v8. Another reason I want it is because there is more potential, let money doesn't become an issue. Also, how many cougars have v10? I got a buddy with a 2004 SVT cobra and its a 4.6 dohc with 15psi, its around 470hp. But without spending alot more money, it wont go any higher. Granted the v10 does have small pistons (3.58" at greatest). But with a turbo or two, a v10 beats v8 by numbers any day. I do realize all modular Ford truck engines are dogs. Even the lightning, it still doesn't compare weel with a v6 turbo syclone. Hell my 05 GMC Sierra with v6 will stay with the Ford 5.4L v8 on the highway! Its the way they let these engine's breath. They will flow more air if you let them, but after the environmental act, air flow/fuel cost was decreased by means of air restriction/stupid thermocool systems and EGR junk. The v10 came in a NON-PI and PI which is Power Immprovement. Its about another 20+hp from stock i believe with or without the EGR. Aluminum heads on v10 would be nice but they are prototype on the new Shelby. These engines put around 355hp at 3300rpm and 455lb-ft peak trq at 3250rpm. Cam will change that, bring torque closer and increase hp. The rods and piston's I hear are junk, but some -18cc forged pistons would hold up the nitrous i want, some eagle rods will match. Hardest thing about this engine is to finding parts, getting 8 pistons is easy but 10? I would liek to increase rod length and stroke in the engine but I am affraid of the deep side skirts will get in way. Howe safe is it to mill side skirts to fit longer rods? I guess depends on depth of piston, If I go with shortest piston possible borderlining oil consupiton through rings, I can suffeciently be able to increase rod length, in return more torque, which has always been my favorite part of engines. Combined with stage3 head work and bigger valves. I think I can break 500hp without additives(nos/turbo/sc). When changing air flow on a v10 it is a more profound advance than a v8 because of the extra two cyl. V10's respond to bolt ons better than v8's just becaus eof this fact.

88 XR7 6.8L 420ci V10

Reply #7 – June 13, 2007, 12:56:11 PM

If you want to put in a V10 just to put in a V10, more power to you. However, if you think the V10 is inherently superior to a stroked 351...I've got some ocean-front property in TN I'd like to sell you.

A V10, V8, I4 will all respond similarly to an increase in charge flow.

Similarly?

Reply #8 – June 13, 2007, 04:02:46 PM

Uhm not quite... I4 revs different than a v6 similarly a v6 revs different than a v8. if you don't beleive me or are just to ignorant to know. ask some one who drives a inline4 and feelhow it revs then feel a v6 then a v8 what it seems is that as the crank increases in length, the recoil of piston 10 to piston1 is greater than those why a v10 requires a forged crank from stock! when a v8 is fed, it is not as crisp as a v6, this is because of a shorter crank, jsut as a inline 4 in a honda is extremly crisp. as the crank length increases, so does lateral stress on the crank, thus requireing not only a forged crank but also angled studs in main caps! this is a very tough motor!

88 XR7 6.8L 420ci V10

Reply #9 – June 13, 2007, 04:31:11 PM

An engine is just an air pump.

88 XR7 6.8L 420ci V10

Reply #10 – June 13, 2007, 06:53:27 PM

Quote from: ztrane;154012

Uhm not quite... I4 revs different than a v6 similarly a v6 revs different than a v8. if you don't beleive me or are just to ignorant to know. ask some one who drives a inline4 and feelhow it revs then feel a v6 then a v8 what it seems is that as the crank increases in length, the recoil of piston 10 to piston1 is greater than those why a v10 requires a forged crank from stock! when a v8 is fed, it is not as crisp as a v6, this is because of a shorter crank, jsut as a inline 4 in a honda is extremly crisp. as the crank length increases, so does lateral stress on the crank, thus requireing not only a forged crank but also angled studs in main caps! this is a very tough motor!

5.4's have forged cranks and four bolt mains too, at least the one I took apart in an '00 F-250 that spun a bearing did...

As for crank lengths - inline 4 and V8 cranks are almost the same length. The only difference in length between an inline four crank and a V8 crank is that the rod journals on the V8 are wider. V6 cranks are generally shorter than both.

Usually what determines how "crisp" an engine revs is its stroke - a shorter stroke engine will rev higher and faster than a long stroke engine. The V10 is a long stroke engine (I believe same stroke as 5.4) and will not be rev happy without major modifications. The two extra cylinders in a V10 are also gonna give you two extra cylinders' worth of friction and pumping losses.

Believe me - you will never get the 6.8 to generate the same kind of power a 410-427CI stoker Windsor would generate. The Windsor has aftermarket parts out the wazoo, while the V10 has very few. Just in cylinder heads you've got about two dozen choices for a Windsor...

88 XR7 6.8L 420ci V10

Reply #11 – June 13, 2007, 07:34:23 PM

Quote

As for crank lengths - inline 4 and V8 cranks are almost the same length. The only difference in length between an inline four crank and a V8 crank is that the rod journals on the V8 are wider. V6 cranks are generally shorter than both.

it...i was gonna say that. nice point Carm

88 XR7 6.8L 420ci V10

Reply #12 – June 14, 2007, 04:13:32 AM

What is your goal? Max HP and TQ?
I am all for building a better mousetrap, but sheesh....
As others have said, you can build a 302 or 351 based engine that will blow away your V-10, normally aspirated or power-assisted. The parts and technology are easily and cheaply available. It will be lighter and fit your chassis and body.
Now, if you are really Bill Gates and just want to be different, go ahead.

88 XR7 6.8L 420ci V10

Reply #13 – June 14, 2007, 04:29:11 AM

well on the topic to provide some input with v10.... to my knowledge... 5.4= stroked 4.6 and 6.8 is 5.4 with 2 more cyls... rods and pistons interchange from 5.4 to 6.8 check this out http://www.sullivanperformance.com/YVS450/tech/tech.htm that may be able to help some more... i was lookin at whipple and kenne bell superchargers for them... no longer made hope this helps if ya got any more questions feel free to ask and ill see what kind of input i can provide

88 XR7 6.8L 420ci V10

Reply #14 – June 14, 2007, 11:15:33 AM

Don't mean to rain your parade here, but you have misinformation out the wazoo.

It should hold up to 600hp safely - No, not really. Remember when Ford built the GT(40 not Mustang)? The Navigator cranks kept failing like mad because of an over-chamfered transfer area on the crank snout. That is why the GT, and now the Shelby GT500, have a completely different crank. This fix never made it to the lengthened V10 crank. Hot Rod had a very in-depth article on this problem and engineering fix. In fact, Ford's "Boss" V10 Mustang test car had a 1-off billet crank because they blew the original in the exact same manner.

I want a v10 over v8 because of the way it winds up - Again, as mentioned, stroke is what gives an engine it's rev characteristic, not type/size/# of pistons.

Another reason I want it is because there is more potential, let money doesn't become an issue - Unless you custom make everything out of billet one piece at a time, a 5.4 will rock the V10's world dollar for dollar and HP for HP. And this is being admitted by a public mod-motor hater.

Granted the v10 does have small pistons (3.58" at greatest). But with a turbo or two, a v10 beats v8 by numbers any day - No. Put the exact same 2 turbos on any engine with greater efficiency and it will kick the V10's butt. A 5.7 LS1 with one turbo would rock a V10 with 2 of the same turbo. It's all about total cfm. IIRC, even the stock 3V 4.6 heads flow more total cfm to 8 cylinders then the PI V10 heads flow to 10. Just an air pump.

They will flow more air if you let them, but after the environmental act, air flow/fuel cost was decreased by means of air restriction/stupid thermocool systems and EGR junk - No, it's called engineering on the ports and configurations. There's a reason the cathedral chamber LS1 heads outflowed all other production ports, they were designed too. Ford FINALLY has some head flow down in the 3V heads.

Aluminum heads on v10 would be nice but they are prototype on the new Shelby - The GT500 uses a 5.4 V8. Even cutting them open for another cylinder wouldn't work to put them on the V10. And the GT500 uses the same head as the GT(40 not Mustang)

These engines put around 355hp at 3300rpm and 455lb-ft peak trq at 3250rpm - When pigs fly. The V10 is a dog. It's been criticized, over-rated, sued over, and recalled. A 5.4 tows better then the V10. It's a motor and Ford knows it.

Cam will change that, bring torque closer and increase hp - First find somebody to make cams for it.

I can suffeciently be able to increase rod length, in return more torque, which has always been my favorite part of engines - Rod length has nothing to do with torque production. Given identical ci's and bore/stroke on identical engines with the only difference being rod length, nothing changed. And this was on 600HP big blocks. Do some research, there's a lot of nice technical books floating around by world renowned engine builders about this.

Combined with stage3 head work and bigger valves - By who? The 4.6 still doesn't have serious aftermarket head support (porting only, no 100% aftermarket heads STILL) who's going to make a V10 head?

When changing air flow on a v10 it is a more profound advance than a v8 because of the extra two cyl - Except the V10 will never outflow the 3V or 4V heads for the V8's in total cfm, so it will never make more power.