Procharger for a 1994 GT
- Thread starter B.mad
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yes we are talking about centrifs..i dont really like turbos in a manual, and roots look weird on a distributor motor.
hmmmm if the power starts letting in the rpm range, that might be to some advantage since i dont want that surge of power going into and during turns, but want the power when im exiting the turn and into a straight. I think best of both worlds is a strong N/A motor with the blower as the adder. which is what i plan to do with a good engine builder and tuner. obviously for street and track you want that power to get you moving through the turns, but you need that power for the straights. hmmmmm...things to think about. But another obvious thing is when i do build the motor up, ill be running it N/A for a while and then slap on the centrif.
also as far as cubes, what do you think its better? i am going to get an aftermarket block and forged internals. but should i keep the 302? do a 306?331? 347? i dont want to do a 351 swap because idk, i like keeping it "original"..its a preference.
DavidBoren
Active Member
I get the whole "keep it original" thing. And on that note, I would keep it at 302ci. I'm a proponent of big heads and little cams, and I value compression over boost. Turbo motors are pathetic when not in boost because of the low compression ratio. So, and this is just me, I would stay around a 9.5:1 compression ratio, maybe even 10:1, and just use relatively low boost. Build the engine to redline above 7k, and drive the p!ss out of it.
Granted, if I was to ever get my hands on a 4-bolt 302w block, I would buy a set of big valve closed chamber Cleveland heads, and I would build a true Boss motor.
Granted, if I was to ever get my hands on a 4-bolt 302w block, I would buy a set of big valve closed chamber Cleveland heads, and I would build a true Boss motor.
DavidBoren
Active Member
I was just going back through this thread, and I saw that you asked about heat soak. Sorry I missed that earlier.
Heat soak is when the heat from one hot part heats up another part. In terms of superchargers, it is usually brought up as an argument against top-mount blowers. Roots-type superchargers produce a lot of heat. And they are generally bolted to the top of the engine. Engines are hot. Heat rises. Supercharger is on top of the hot engine. You get the picture.
If you have ever seen those phenolic spacers for intake manifolds, they are designed to reduce heat soak.
All of this relates to heat being the enemy. And this is why it is crucial that you build a top-notch cooling system. I know you don't plan on running a valley-mounted blower, but any form of boost is going to generate a lot of heat.
Heat soak is when the heat from one hot part heats up another part. In terms of superchargers, it is usually brought up as an argument against top-mount blowers. Roots-type superchargers produce a lot of heat. And they are generally bolted to the top of the engine. Engines are hot. Heat rises. Supercharger is on top of the hot engine. You get the picture.
If you have ever seen those phenolic spacers for intake manifolds, they are designed to reduce heat soak.
All of this relates to heat being the enemy. And this is why it is crucial that you build a top-notch cooling system. I know you don't plan on running a valley-mounted blower, but any form of boost is going to generate a lot of heat.
I originally looking at a 331 stroker kit that will give me 9.7:1 with 58cc heads. would a 331 rev better than a 302? because its a lighter crank?
this was my build list for a road racing motor
ford boss block
forged interals
custom FTI cam
afr 195 heads with upgraded springs
holley systemax intake port matched to heads
and 60lb or 80lb injectors
with a forced injection (not sure which one ill go with)
and possibly a stroker (if i decide to)
i dont know much about cleveland heads
and the advantages...please enlightenDavidBoren
Active Member
Back in 1969 (I believe), Ford took the heads off of the 351 Cleveland and put them on a 302 Windsor motor. The block had 4-bolt mains and was stuffed with forged internals. The heads they used were the big valve, closed chamber heads meant for use with the 4-barrel carburetor.
The Cleveland heads use canted/offset valves, and flow a ton better. They require the use of pistons with matching valve reliefs, and water passages in the head need to be matched to the water passages in the block. And a special intake manifold needs to be used, as well as stepped diameter head studs.
Anyways, Ford named this beast of engine the 302 Boss. It's why the Ford Racing 4-bolt block is called the Boss block. It had big heads and a relatively little cam, and they revved the hell out of it, especially to 1969 standards (6000+rrpm's).
The Cleveland heads use canted/offset valves, and flow a ton better. They require the use of pistons with matching valve reliefs, and water passages in the head need to be matched to the water passages in the block. And a special intake manifold needs to be used, as well as stepped diameter head studs.
Anyways, Ford named this beast of engine the 302 Boss. It's why the Ford Racing 4-bolt block is called the Boss block. It had big heads and a relatively little cam, and they revved the hell out of it, especially to 1969 standards (6000+rrpm's).
DavidBoren
Active Member
Double post. My bad.
And no, a 331 will not rev better than a 302. Generally speaking, your shorter stroke engines will tend to rev easier. Increasing the stroke usually lowers the redline. Granted, there are people spinning 4" stroke 400ci motors above 7000rpms, so it's not to say that you can't spin a 331 just as fast as a 302.
And no, a 331 will not rev better than a 302. Generally speaking, your shorter stroke engines will tend to rev easier. Increasing the stroke usually lowers the redline. Granted, there are people spinning 4" stroke 400ci motors above 7000rpms, so it's not to say that you can't spin a 331 just as fast as a 302.
I knew the whole thing with the 351 heads on a 302 called boss 302, but i didnt know the specifics (till now). with that being said, if i did go the cleveland route, will i need to do a carb swap? because i am not up for that LOL. If i get a boss block, the internals will probably be the weak point. I am not familiar with how the materials differ in terms of revving. I know it has to do with heat. is revving and heat dependent on each other? for example i have a motor that can be revved to 7500 rpm whether it be a 331 or 289 doesnt matter. Will a forged crank take that kind of abuse? and will a "small cam" will give me a linear curve through out the rpm? is the curve in the design of the crank? or how does this work
only reason why im asking is because i want the motor to last as long as possible. i know i know "why build a motor if you're worried about reliability an gas mileage"...but theres nice reliable motors out there so it is possible. I dont want to say money isnt an issue, because i am not rich. But in terms of saving money, it wont be an issue. as long as it isnt like a million dollar motor or something (hyperbole). also this motor is going in a DD, so streetable is an issue. and it wont be revved past 6500 rpm all the time, just when its tracked which will be either 2 times a month on a 1.5 minute course and/or one weekend a month on a 30 min course. The reality is, this motor will se traffic and some street and highway driving a poop ton more than a race.
DavidBoren
Active Member
Simply put, the faster you spin the motor, the more heat you will produce. Forged components are built in a way that allows them to handle the heat associated with high rpm's and/or boost. Forged internals generally last longer, so they would be a wise choice in your quest for reliability.
You seem to want a 331 stroker, so build that. A forged rotating assembly will cost you the same whether it's 302ci or 331ci. You can safely rev both to 6500rpm's with the proper valvetrain.
If you build a Boss motor, with Cleveland heads, you don't have to convert to carb. But... the only Windsor block/Cleveland heads intake manifolds out there are for carburetors. So you have to either have injector bungs welded in and fuel rails made, or use a 4-barrel carburetor type efi system.
You would probably be a lot better off just buying some trick flow or afr heads, unless you are after the novelty of building your own Boss motor... which is wt I want to do.
You seem to want a 331 stroker, so build that. A forged rotating assembly will cost you the same whether it's 302ci or 331ci. You can safely rev both to 6500rpm's with the proper valvetrain.
If you build a Boss motor, with Cleveland heads, you don't have to convert to carb. But... the only Windsor block/Cleveland heads intake manifolds out there are for carburetors. So you have to either have injector bungs welded in and fuel rails made, or use a 4-barrel carburetor type efi system.
You would probably be a lot better off just buying some trick flow or afr heads, unless you are after the novelty of building your own Boss motor... which is wt I want to do.
While stroke increase will usually not allow you to rev as far, most stroker engine kits (331 included) usually changes the position of the wrist pin on the piston, and has longer rods. This means that the working angle that was changed by making it a stroker gets returned back to normal. My 331 stroker revs to 6500, and feels like silk at that engine speed. By comparison my stock 302 felt like it was going to fly apart at 5k rpm. There are a lot more factors to rev limits of bottom end other than just stroke.
Ok, i am getting a little confused on the blocks. Here is the link for reference.
http://www.latemodelrestoration.com...ang-50L-Ford-Racing-Boss-302-Engine-Block-Kit
If i get that block, will the systemax intake i want bolt on? will the afr 195 heads bolt on? what about all the accessories and so forth will it be the same? will everything be the same? minus the block of course. because i want everything to be the same (besides the obvious and the upgrades)
hotmustang95
Active Member
I've never run one but someone I know does. As far as I know everything bolts exactly the same as a regular 302. This motor is just stronger. I've also been told that it still needs to be machined before installing the pistons. More $$$$$
DavidBoren
Active Member
I mentioned that there are 4" stroke engines spinning near the 7k range. So yes, a lot comes into play regarding redline than just stroke length.
And also, yes, there is another $1000 worth of machining that needs to be done to prep an aftermarket block. You should have everything you plan on putting on thr block first, then have the block prepped for and assembled with those parts.
And also, yes, there is another $1000 worth of machining that needs to be done to prep an aftermarket block. You should have everything you plan on putting on thr block first, then have the block prepped for and assembled with those parts.
everything minus the procharger..thatll be last lol. i just wanted to make sure it was the same bolt ons. i figured ill need some machining done, but not that much
DavidBoren
Active Member
It might actually be worth funding a 4-bolt shortblock. You can find a complete shortblock, with high volume oil pump, for $3000... knowing it's done right is worth the peace of mind.
http://www.roushyatesparts.com/boss-302-rotating-assembly-kit-p/ryp-boss302a-kit.htm
http://www.roushyatesparts.com/boss-302-rotating-assembly-kit-p/ryp-boss302a-kit.htm
ba#97
Well-Known Member
I don't want to rain on the parade here or anything or get off your original topic but I agree with Rich. and here is why. what makes you think that even when you have enough experience to handle the power, that 350hp wouldn't be enough on the road course? based off what I've read you've had maybe a handful of days out on track in a car with a little more hp. that doesn't necessarily mean that you know how to drive a car with hp on track. (nothing against your driving ability, for all I know you're great). it takes tons of hours on track to learn all the skills you'd need to properly handle a car with 300+ hp on track let alone 500. I see you say you don't want to go with some over the top n/a build to get the hp numbers you want. ok....well instead of doing an over the top n/a build or from what I am reading your intent to do an (in my opinion) over the top f/i build...why not leave the car as is and run it into the ground at the track. the amount of money you want to spend on this build for hp #'s that you don't even need can go straight to spending more time on the track. that's just my .02.
what it honestly sounds like to me is you aren't really as interested in having a track day toy as you're having a cool street car. if that's your goal than go for it. because sadly if you don't take some of the advice that the VERY experienced road racers have on here, your investment in the super charged motor and car you like, you may find out scares you on track, or blows your motor from the heat, or becomes too hard to maintain at a track day, or worse yet....you end up in the fence because you couldn't tame the beast you may have preemptively put yourself into.
I personally think what you need to do is focus on experience on track and having fun. once you're comfortable with your car and know the limit of what you have now, as well as the limit of the coures you're on and are comfortable running around others, then go balls to the wall.
what it honestly sounds like to me is you aren't really as interested in having a track day toy as you're having a cool street car. if that's your goal than go for it. because sadly if you don't take some of the advice that the VERY experienced road racers have on here, your investment in the super charged motor and car you like, you may find out scares you on track, or blows your motor from the heat, or becomes too hard to maintain at a track day, or worse yet....you end up in the fence because you couldn't tame the beast you may have preemptively put yourself into.
I personally think what you need to do is focus on experience on track and having fun. once you're comfortable with your car and know the limit of what you have now, as well as the limit of the coures you're on and are comfortable running around others, then go balls to the wall.
ba#97
Well-Known Member
I'm not saying it's a bad idea. but I am saying it is a bad idea at your experience level. just get out there and have fun.
hottwheels04
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that looks like a nice 331 setup on motor alone that would be around 350-400rwhp easily, so with a blower wont take much to make 500rwhp even on pump gas 8psi of boost should be right around 500rwhp. stock block is the weak link though after 450-500rwhp. I would be safe on it or do a aftermarket block
Ok let me say it again to you because either you didnt read it or i didnt say it properly. lets get something straight here, you and rich are BOTH RIGHT. I am not arguing that you are wrong, i am not saying i am a bad ass driver and i have a shit ton of experience because i dont. I have mentioned it before and i will mention it once more: this build will not take place until about 5 years or so from now. What does that mean exactly? that from now and that time, i will be attending track days, i will be building my suspension, my drivetrain, etc etc, improving my skill and getting experience. All WHILE I HAVE A STOCK MOTOR. of course i want a nice street toy, who doesnt? but i also like to beat my cars up, and i sure as hell not going to do this on the street. What does that mean? IT MEANS IM GOING TO TRACK MY CAR.
I know im being an ass here, but it kinda bugs me when people tell me things that i already know. I am not stupid. I am not going to strap myself to a 600RWHP car and go balls out. with what i have now its a handful. but when i get experience i want something faster and faster and faster (until i hit my 600RWHP mark). I am 20 yo (going to be 21 in a couple months), i might be young and inexperience but i am sure not stupid. I know how to test my limit's and respect my car(s). THis is my plan within the next 5 years (if you care)
rebuilt and completely upgrade my suspension, tires, brakes and chassis
take care of all exterior and interior cosmetics
completely rebuild and upgrade my drivetrain
rebuilt my motor and get a nice N/A build with everything i want (minus the s/c)
then after i am going to s/c it.
do you see what i mean? i know what i am doing (in a sense), i am not going all out, i think suspension is more important in a track than a motor. i dont even have the cash to do a build like that. so it just doesnt make sense for you to assume i am going to go all out before i have experience. I reallllly appreciate you and rich looking out for me, honestly because i am a complete stranger and you actually i guess kinda care for a strangers well being. that right there is character. But i would also really appreciate it if you didnt assume i was that stupid, and instead ask some questions before jumping to conclusions.
