302 build help

dadslx

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Nov 11, 2006
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hello need some help here. building a 89 302 efi motor for the use of a turbo.

what i would like to do since im on a budget. engine is bored over .030.
need to obtain a c/r of 9:1
using gt40 heads ported large valve 1.94 int 1.60ext not done yet just a idea. cc???
trick flow street burner intake with 75mm t/b
stock crank
aftermarket rods forged h or I beam? what length?
forged pistons .030 bore ??? no idea here
f303 cam
any input or ideas would be great.
goal is 450-500 hp 15 psi of boost on a 60 trim
 
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If you go .030 on the block bore then you will need .030 pistons. Go with forged aluminum. I prefer H0Beam rods...I'd ditch the stock crank and get a forged one. And you might as well do a stroker since the engine is already gonna be out and you're doing all upgraded internals anyway. I wouldn't go more than a 331 for a turbo build.

With a set-up like that you can probably make your desired hp with less than 15lbs of boost...
 
Are you using a stock block? If so...don't waste your money putting a forged crank and rods in it. I keep saying, putting a forged rotating assembly in a stock 5.0 block is like parking a Ferrari in wobbly, old shed.

If I were building a high boost, 500+ horsepower shortblock, I would do one of two things.

Put an old, bone stock lowest dollar possible shortblock in there....because it's just gonna go kaboom in time anyway. Or...

buy a Dart block and put in a forged stroker rotating assembly and run the hell out of it....forever.
 
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Are you using a stock block? If so...don't waste your money putting a forged crank and rods in it. I keep saying, putting a forged rotating assembly in a stock 5.0 block is like parking a Ferrari in wobbly, old shed.

If I were building a high boost, 500+ horsepower shortblock, I would do one of two things.

Put an old, bone stock lowest dollar possible shortblock in there....because it's just gonna go kaboom in time anyway. Or...

buy a Dart block and put in a forged stroker rotating assembly and run the hell out of it....forever.
I see your point Jason 302 and I agree to a certain extent. However there is a chance that he'll snap a rod or crack a piston way before he does any damage to the block. So why take a chance? I'm not saying that it's gonna happen either which way. But I am saying that it would be silly to have to replace an engine because you snapped a stock piston when you had the opportunity to put upgraded stuff in there in the first place. If you crack the block then it would be less of a sting IMO. Besides, his hp goal with the setup he has can be attained without high levels of boost if it is tuned properly and if he uses a stroker. And if it's just for street use then I think the stock rotating assembly will be the weak link before the block gives in.
 
yes it is a stock block. Well with the block i have it was free so i wasnt too concerned with what might happen to it. i think with everything said i may just simply upgrade the top end and run a low boost 7-8 psi on the stock bottom. when it finally does go i would way my options out for a new block. keeping the 302 since i will have invested money into top end parts. or maybe just build a top end and save for a dart block or something of that nature then go turbo.
 
Prepped stock rods (ARP bolts) and stock crank will outlive a stock block...the nodular iron crank in a stock 5.0 is a very strong unit for being as light as it is and externally balanced. The rods are also quite strong-despite the tiny 5/16" bolts. That being said, if you gotta stay stock bottom end due to budgetary constraints, get a set of probe fps 2456-030 slugs and they'll yield you about 9.2:1 CR...they mimic factory pistons quite well, bolt on your gt-40s, balance your bottom end, and the F-cam does pretty decent for turbos so I'm told...never tried it though. Go conservative on your tuning and have fun with it, but try to keep the power below 500rwhp.

...if you can save up though, and you want to achieve your hp goal with plenty of breathing room, go for the 4-bolt forged bottom end option. A build 4 bolt shortblock is about $4200 last time I checked, and it'll take whatever kind of power level you can reasonable heave at it...I'm with Jason on this one.
 
But I am saying that it would be silly to have to replace an engine because you snapped a stock piston when you had the opportunity to put upgraded stuff in there in the first place

"snapping" pistons happens due to aggressive tuning...regardless of stock or aftermarket. I received a set of used Diamond slugs from a friends engine to use in my upcoming build...said they were just in need of a cleaning. During the cleaning, we found multiple cracks around the pin boss, and flame pitting around the crown...$800 pistons doneski because someone got too happy with the timing under boost.

If you crack the block then it would be less of a sting IMO

Not really...if you thrash a stock block, there's a reasonable chance of damaging some of the expensive internals...

And if it's just for street use then I think the stock rotating assembly will be the weak link before the block gives in.

Again, a prepped set of stock rods and stock crank balanced with new pistons will outlive the factory block...this I have seen with my own two eyes...too bad I didn't have my camera. Stock balanced 5.0 bottom end H/C/I, and bottle fed...after about a season of low 11s-high 10s, it finally had enough. The loss of oil pressure caused damage to most of the journals on the crank, and overheated the big ends of half the rods...scuffed some pistons...etc. If not for the heat damage, the rods would've been good, and the crank was fine, but would've had to be turned more than the owner was comfortable with.

Just my .02...
 
I think his name is ironhead498...70mm turbo on a cast piston t-bird bottom end with TFS heads and cam pushed over 500rwhp...and didn't miss a beat. But, he also knows good and well it's not going to live long with that setup. And I'd almost throw money down that the block would give before the guts.
 
txstang84...I think it all comes down to preference or what each individual is more comfortable with. I have heard arguments going both ways. I know people who have cracked blocks and I know others who have snapped rods and cracked pistons. I even know some who broke cranks before anything else went. Me personally, I would not worry abouth the block at the OP's desired power level but that's just my opinion. If it were my car I'd upgrade the internals. True, detonation can destroy a piston whether it's forged or hyperute...but a forged piston will take a lot more of a beating than hyperute. That's just what my experiences have taught me, others know or have seen differently...
 
three50won, I'm sure the only point Jason and I were alluding to was that putting forged internals into a stock block is only injecting extra cost into a combination that is likely to fail anyway and take the expensive goodies with it...furthermore, it's my own interpretation that if you put a turbo setup on a car, you'll very likely want to turn up the wick on it one day just to harden the callouses on your behind because you got so used to the power level before. When you do that, *something* on that stock block-regardless of the contents-will fail. If it's the block, and full of expensive forgings, you might take them out with it. But, if he builds up the stock pieces *correctly* (i.e., good rod bolts, main studs, balancing, blueprinting-things you would do with forged internals anyway) with a good set of pistons and tunes it effectively, the engine will live well and provide him with plenty of :D for a significantly lowered cost before it finally gives up the ghost...

6 of one, half a dozen of the other...but the forged internals will only boost the price tag of mangled heap of parts in the long run. We can probably go back and forth on this until our respective keyboards are worn out. My only hope is that we're providing the OP with some good entertainment ;)
 
three50won, I'm sure the only point Jason and I were alluding to was that putting forged internals into a stock block is only injecting extra cost into a combination that is likely to fail anyway and take the expensive goodies with it...furthermore, it's my own interpretation that if you put a turbo setup on a car, you'll very likely want to turn up the wick on it one day just to harden the callouses on your behind because you got so used to the power level before. When you do that, *something* on that stock block-regardless of the contents-will fail. If it's the block, and full of expensive forgings, you might take them out with it. But, if he builds up the stock pieces *correctly* (i.e., good rod bolts, main studs, balancing, blueprinting-things you would do with forged internals anyway) with a good set of pistons and tunes it effectively, the engine will live well and provide him with plenty of :D for a significantly lowered cost before it finally gives up the ghost...

6 of one, half a dozen of the other...but the forged internals will only boost the price tag of mangled heap of parts in the long run. We can probably go back and forth on this until our respective keyboards are worn out. My only hope is that we're providing the OP with some good entertainment ;)
NO, I'm right and you're wrong...hahaha, just kidding pal, and I didn't mean to come off that way earlier. Yea sometimes I forget the cost factor. And I sometimes forget that we're dealing with 2-bolt main blocks. Those blocks aren't exactly the toughest kids on in the neighborhood, hahaha. Sorry if I sounded confrontational...I was at work and half-sleep when I wrote my responses and I failed to look over what I was typing...my bad bro...
 
Not at all dude-I just saw it as asserting your opinion...I was doing the same. 2 bolt 5.0 blocks really can be hit or miss. A friend and I built up a blown/forged 331 in an E7TE block pulled from a salvage yard-it was a truck engine based on the flat tappet cam and HUGE intake. The engine made great power on a very conservative tune and only 6psi boost (460+rwhp...in Dallas..95*, 70% humidity). It was a blast to drive and tons of fun...until it started drinking coolant. We had the heads off the engine on 4 separate occasions IIRC trying to figure out why. After the final time this happened, we top-halfed the engine and I inspected the bores on a whim; up until this time, we figured it was intake or head gaskets failing. The #4 cylinder had a 2+" crack on the thrust side of the cylinder. Long enough that when at TDC, it would drop water in the oil, and at BDC would drink it. We did everything right on the engine build, we even installed the super-trick looking DSS main support system and windage tray. The machinist did everything right...when we later told him about it, he was a little surprised and chalked it up to porosity (a casting bubble) in the cylinder core...basically poop happens. Obviously, that was no consolation for a guy who spent probably $600 just on block prep, $200+ worth of head and intake gaskets, weeks of downtime on the car because of TDYs, 12 hour shifts, other obligations, and need for sleep. Let me also throw in there, this was in a '95 Cobra...and I don't know if you've every had the dubious honor of doing engine work on one of them, but the SN95 5.0s absolutely SUCK to work around. The accessory brackets are huge, bulky, and a PITA to install; seals and hoses aren't made for the oil cooler, so we had to cobble all that crap together, and there were various other inconveniences when compared to a Fox. He finally bought a plain jane forged piston 306 from the local wholesale engine place because of lack of time to build the 331 back up. He optioned it with ARP bolts and we swapped in his old main studs, and a couple other parts salvaged from the old block. After putting everything back together, it still made 420rwhp...with 30 less cubes, and from a basically stock engine with cheap forged pistons.

...then some clown stole the car.

Sorry for the hijack and long-winded reply. Just thought I'd throw out the personal experience.
 
Go to all the trouble of building a respectable car and then someone steals it. That sucks man. I've never had a car stolen from me but I know I'd be devastated if it happened to me. I think I'd feel a bit violated...because to me your car is yourself.

Anyway, yea the dart block is the best way to go. I went out on my patio and looked at my bare 351W block sitting outside in all it's 2-bolt glory...not confidence inspiring for most folk to say the least...
 
Hey guys. i was just wondering.. i should make my own forum, i am new to the forums, Ever to be honost.. anyways along time ago about 12 years ago i had a 1966 coupe hardtop with a 302 bored .20 over with a weiand highrise alum intake a carter afb 650cfm "some where around 650 i forget what it was on the stamps" and im thinking a RV cam with stock distr runing single points and a accell coil, no msn <--- "ment MSD," or anything, anyways with a C4 tranny, dont know if it was ever rebuilt or a shift kit in it when i got it from my brother who had got it from his boss and burger king, a woman owned it and the intake formed a leak of colant due to straight water in the radiator, anyways my brother bought the car for $1000 and i fixed the car for him and had the intake repaired, never noticed anything was wrong when it was fixed, anyways with a B&M shifter,
i bought it about 2 years later for $900 off of him, it could go 60mph in first, 80 in 2nd and 135 in 3rd but was kinda slow getting to 135 once you got to 125, and had stock manifolds,
i could get the wheels off the ground about a inch or to after i installed traction bars on it, i "Was" getting 20mpg going 70-75mph down the interstate, "between phoenix and tucson arizona where i lived at the time"
but if i got in it and was heavy on the foot it would get around 5 mpg lol, anyways i was wondering what would be best. i just got a 1965 mustang coupe with the stock inline 6 and small c4 4 bolt lugs, for $1200, it runs and drives yes after i put a autolite 1101 carb on it because the one that was on it the venturi was melted and you cant find them anywhere and the carb was $50 off ebay, it needs floor pans and trunk pans with the rear valence and rear frame rail, other then that the whole car is in once piece with nothing missing.. the inside does need restored but its just all faded and crappy paint job done by prev' owner, but for the price i couldnt pass it up, i have a 302 shortblock complete stock bore from a 1979 capri, with the duraspark 2 dist, i want to rebuild it and put a good rv cam or a little bigger in it thats going to be around $800 here in campbell, MO. and the machine work on the steel stock heads that i am trying to pass on, ebay has a set of alum heads with 210 runners, 2,02 exh 1.80 intake valves with springs but no rocker arms for $399
so i still need a intake a carb and a few more things to get it running, or get a 1990 mustang LX with a 302 in it that runs and has everything so it runs with a good size cam in it with a C4 tranny for $1000?
i could just set the motor in the car and hook it up and im driving with a 302, or put the time and the $1000 into the 302? i will need around $1600-1800 in the motor alone to make it running if i go that route.. but is it better to do it yourself and know whats in it or just get it running? the running 302 has the stock shorty headers on it that came in the mustang the motor was pulled from before installed into the 90 lx, it does not look like the stock motor,, looks like a 4 cyl car made into a v8, anyways. what should i do? and is it better to go roller or stay hydralic lifters? some engine machine shops say stay away from roller while some say those alum heads i talked about with a E303 cam would be a screaming demon, im not sure what to do. besides that.. all the engine install and putting together i do myself so all the money would be parts and machine work on block/heads,
 
sorry, have been having a bad time. last night sunday 1-22-2012 at 6:40PM i lost my son "in the picture with me" to a fight against Childhood Brain Cancer called a DIPG, he only lived 9 months after he was diagnosed with cancer in the brain stem on april 5th 2011, today we go meet with the funeral home, yes i shouldnt even be on this.. but it really helps clear my mind and thinking of his "in memory of" car, it has been the hardest 9 months of our lives and im sure it only will get worse for a short time untill we get used to it, anyways back to the forum, there was lots more that i posted but i guess it was to long, better to buy a crappy "but running" 302 with a C4 tranny already and a duraspark2 ignition already or start from a bare "but complete" block rebuild and have to buy a intake and carb and all that stuff.. more less around $1800-$1900 into the motor or $1600 into a motor and tranny.. "btw i can get a C4 about 45 minutes from here from a 79 302 car for $50 that still works great" im not sure what i should do,, money is the real issue, $2000 is about all i have at this moment, "the money is from my income tax refund" anyways R.I.P Matthew!
http://www.caringbridge.org/visit/matthewbrown6
 
I am sorry about your son.

thanks, today and tomorrow will be the hardest days while we lay him down for the last time, we will miss him.

anyways, so many motors out there.. so many options! i guess before you start anything you really need to know what it is you do want and not just jump into everything, i guess im going to build my own engine but the thing is, do i go roller? or do i go hydraulic? i can get a complete roller block with gt40P heads and a tranny with the computer and wiring for $600, im almost ready to jump all over that one. it was from a 97 explore, and its a complete engine.. with the injecters intake everything.. alt, powersteering pump a/c the whole kit. but its been sitting for a few years and both need gone though, so theres more $$$, the block i have i can get all the machine shop work, complete engine rebuild kit and heads worked on <the stock or ones i buy and bring in> for $800, but there is always needing to buy a intake and carb, i am really good at adjusting my own carb and timing, i used to do it by ear with my old stang and it ran like a dream, i can get alumium heads 210 runners 2.02 exh, 1.80 intke, for $399 + free shipping,, but then i still have to buy rocker arms, but my understanding someone said a roller motor and a e303-f303 cam would make major hp and torque more then a hydraulic cam motor would, with just the alum heads, anyways i'll get back to this later, thanks, any comments welcome! i know how the forums are now adays.. lol lots of comflict between others on what is better and whats not.. haha all is welcome!
 
What's the end goal/wants for the car to achieve?

Be careful with the 210cc aluminums for that cheap...they're probably bare castings and need all parts-plus, anything that cheap...well, I think you see where I'm going with this. And if you're using stock pistons, they might need to be notched. Honestly, the GT40P heads aren't bad-they will limit you, but they're tons better than their predecessors. If you just gotta have aluminum though, look for a set of trick flows, edelbrock, or holley...they're all decent heads, will behave well on the street, and accept all factory accessories...AFRs are nice too if you can find a good price on them. I'm not saying the inexpensive ones you mentioned won't work-I'm just a little leary of something *that* cheap for such a major component.

The FRPP alphabet cams are ok if you're not looking to maximize your combo, need to keep lift numbers down, or can't swing the extra for a different cam (I bought a new in box F cam for $110 a few years back for a project engine-used ones can be had cheaper) . Everybody and their brother and jack leg cousin used to have E cams...they'll give you a little lope, and better power than stock but it's not like you'll turn it into a barnstormer. The F cam is a little bigger and will give some improvement, but you're still dealing with older single pattern cams that can't maximize power in most cases with a good set of heads. Standard flat tappet hydraulic cams just have the disadvantage of needing to be broken in on first start up. I've also seen a couple of them go flat if you don't use the correct oils-not isolated incidents. Many of the major oil companies have removed heavy metal compounds from their oils to reduce emissions (zinc, manganese)...with older engines using flat tappet cams which were made of comparitively softer materials, these compounds lubricated the lobes and staved off premature wear. So, you have to be aware of what kind of oil you're using....just stay roller and you'll avoid the whole thing.

If you're planning to run carbed with a duraspark type dizzy, get one from autozone or wherever that fits an '85GT...with the steel gear. If you run a standard iron gear, it will eventually shave down because roller cams are made of harder materials. I think I paid $65 for a reman'd one and that was including the core charge since I didn't have a turn-in part.

There's much more to it, but the '97 explorer engine would be a good investment. There's quite a few folks on here using them and they run great...

Edit: I'd almost suggest keeping the EFI unless you just don't feel like tackling the wiring and fuel system upgrades...they're not difficult, but can be time consuming...if you do some searches on here, I think you might find one or two folks that have dropped the EDIS explorer 5.0s into their Mustangs. The headers that come with that engine may not fit; if tri-y's fit GT40Ps, I'd go for those since I know they'd fit a classic 'stang...just a thought.