Need some engine building advice

[wicked93gs]

Ok, heres the deal, I am wanting to build a 400HP block, but I will use a turbo to get there(probably a GT35R...but I can decide on that later) now...400HP isnt a lot as far as SBF engines go....and I dont want to spend money where its not needed either...I want a block thats good to 450HP(give myself some safety margin) I have heard people say that the stock block can take this...well, that may be so, but I need to rebuild the block anyway....heres my plan, tell me if you think it will work

Roller block(havent decided on which one yet...probably whatever I can find at the junkyard)
GT40-P heads
Sealed power engine rebuild kit w/hypereutectic pistons(this type of piston it has been suggested in maximum boost might work best in a turbo engine, I currently have forged pistons in another turbo engine of mine, but would rather use hypereutectic assuming they will hold up to my power target)
Camshaft-undecided, suggestions are welcome...something mild with higher duration but low overlap....after all, my power is coming from boost, the cam is mainly to change my powerband around
Roller rockers-This is my first pushrod V8 build so I dont really understand what all they do...from my understanding, the stabalize the valve at higher RPM, preventing valve float? If I buy a set, do I need stiffer valvesprings?(for a mild cam) What ratio would I need? What does the ratio even mean anyway?
For 400HP would I need a block girdle?
Can I get away with the stock rods and crank for a goal of 400HP?

As you can see, lots of questions, I'm trying to keep the money in the engine down, but I'm not going to skimp where it will do some good, but theres no reason for me to buy forged pistons when hypereutectic will do, no reason to buy forged rods if the stockers will do...etc, etc, one thing I do want is high RPM valvetrain stability...while I dont plan on revving the engine out too often, I dont want to worry too badly about valve float. I'm not worried about the fuel system right now, I can cover that easy enough with other parts I have around, its all going in a 66 if that makes any difference...MegaSquirt2 for EFI, so I have full spark and fuel control

 

[BarnStang]

THe roller rockers eliminate the friction of stamped steel rockers. THe tip has a roller that rolls on he vave stem, and the center part has roller bearings. Same principle as the roller lifters.
THere are others here that can address the rest better than I can.

 

[hipo_p51]

plan on spending 8 to 10k if u have a shop do the work. sorry to say, but the words 'keep the money down' made me laugh.

 

[thekid760]

If you only want 400-450hp, You can relatively easyily do that with just a 347 stroker engine, you wont need a turbo. Use the money you save from not having to buy the turbo and spend it on quality parts and a custom camshaft.

I'm not an expert but I dont think hyper pistons and boost go well

What are you goals for the car? street, strip, road race, show car?

 

[wicked93gs]

ok, let me make this clear, I am an experienced engine builder, and have built half a dozen turbo engines...just not a pushrod v8....anyway, the car is a street car...maybe a bit of track time now and then...and I know I could get 400HP NA relatively easy...but I like turbos for several reasons, not the least of which is they dont really affect fuel mileage much while no in use...as for the pistons, generally the weak point of any engine is not the pistons, when it comes to boost, rods tend to go first(its not like I'm using nitrous)

now, its perfectly possible IMO to keep the cost down for anyone who does their own work anyway

roller block from junkyard-$75
Engine rebuild kit, $350-$550 depending on piston type
GT40P heads $250 used
Explorer intake and TB $60 used
MegaSquirt2 $250 assembled yourself
misc fuses relays, harness, etc $100
the most expensive part would be the turbo...a GT35R would be ideal, but I can do a couple of standard t3s just as well...easy enough to find in junkyards for $50 a piece....though possibly needing a rebuild, rebuild kits cost $100 or so a piece, so say $250 for a couple rebuilt T3s, or some used 14Bs in good condition which wouldnt need it(I have a good source on mitsu turbos)
so roughly $1600 in parts(plus a lot of fuel parts I already have) and of course I would need to fabricate a manifold, but I can do that too(or alternatively I have a couple friends who can if I dont feel like messing with it) so it can be affordable, I know, I've done it before on other cars, Neons, Supras(NA to turbo conversion),etc, I know you're thinking that for that price I could just stroke out the engine to a 347, which may be true(if you dont factor in the cost of the block and heads) but the driveability on any aggresive NA engine suffers, which isnt the case with turbocharged engines(or at least not with mild turbo setups like this one would be)

anyway, enough ranting on prices, still need my questions answered, mainly internals strength

 

[dcstang67]

I happen to have a complete balanced rotating assembly I am looking to get rid of. I just upgraded my engine and I have all this stuff to sell. The crank is a stock srank ground .010/.010. Eagle I beam Rods good for 600HP, Speed pro Forged Pistons .030 over Approximate compression 10.13:1 with a 58.2cc head. You will need new bearings and rings. Let me know if you are interested. I dont know how much it will cost to ship. [email protected]

 

[mrmustangman357]

what happened with all your work on the SHO motor?

 

[ForceFed70]

With what you are going to spend on an aftermarket block and required machining, it really doesn't make sense to cheap out on the internals.

Cheap internals = cheap (stock) block. Either pony up the additional money, or go with the stock block. If you are serious about only 450HP, then go with the stock block (get a 302 with factory hyper's and call it a day). If you think you'll end up turning up the boost (we all do), then either spend the money on aftermarket block with good internals or build a 351W instead. A 351W can handle 600HP with mostly stock internals (only need to upgrade the pistons).

 

[wicked93gs]

what happened with all your work on the SHO motor?

Someone broke into my garage at my old place and stole it and my hoist both...it pissed me off pretty badly...I didnt have the heart to start again

as for the 450hp...I dont need this to be the fastest car out there...hell, my neon is built for 600HP, and I dont run more than about 250(still havent turned up the boost even after a year, too many little issues like wheelspin, more boost is useless until I can get the power to the ground, FWD sucks sometimes). I would like to build a 351, but I hear they are a tight fit in a 66...not to mention a bit heavier, besides, 400 is enough for this car, just going to be a fun daily driver, looks like a stock rebuild will be sufficient for the first round

 

[stonecoldtx]

You can reach 400 naturally aspirated with a 5.0L easily, and without suffering drivability issues.

The Ford Racing 5.0L crate engines put out 340HP, 345 or 390HP, depending on the engine

M-6007-X302B uses the "B" cam rated at 345HP, and M-6007-X302E uses the "E" cam, which is rated at 340HP; they are identical other than the camshafts used.

Both engines use the Aluminum GT40 "X306" heads with 1.94" intake valves, which flow a bit better than iron GT40's or GT40p's

The M-6007-Z302Z crate engine is rated at 390HP and uses the "Z304DA" heads with 2.02" intake valves along with the "Z303" camshaft; this engine also has a 10.0:1 compression ratio, where the other two have a 9.0:1 compression ratio.

Bottom line--with a set of AFR 165 OR 185 heads and a little better camshaft (like maybe an XE264HR, for example), you can make 400HP naturally aspirated, with ZERO drivability issues!

You also can get a set of those heads relatively reasonably priced. I saw a guy selling two sets of NEW AFR 185's on another forum last week for $1150 per pair, and you can get a set of them used for less than that.

Camshaft is around $250, and you can get a shortblock practically anywhere for $100-$350, so if you found a set of use AFR 185's for, let's say $1100, you would have a total of around $1600 in a longblock that would easily achieve the 400HP mark, and be dead reliable; with tuning, a light right foot and the right gearing, you'd probably come pretty close to achieving the same fuel economy as a standard box stock longblock.

If you want to use a turbo, that's fine . . . but if your goal is 400HP, you can do that with a completely stock longblock and around 6-8lbs of boost, OR you can build up the engine I've outlined and achieve the same thing for the same money.

 

[brianj5600]

A junk yard 5.0 and a MPT-70. 400hp and 500tq.