Building a 302 / 3.00" stroke / 8,500 RPM, V-8 Car Options

[drive-ability]

I have started gathering parts to build a large journal 302. This is the engine this car needs to really work. The 350 is made to move a truck, where as a 302 makes the best balance of HP and torque. Ya the parts are expensive about 3 times the cost of a 350 but you only live once. (IMG:style_emoticons/default/beerchug.gif)
I'll keep you V-8 guys posted!

[Twystd1]

I will remind my friends with Z06 Corvettes, They got burned by Chevy with a 400 HP truck engine... (IMG:style_emoticons/default/yappin.gif) (IMG:style_emoticons/default/hitfan[1].gif)

On the other hand.. I assume you are going with the later model 302 roller motor as you are gunna spin it to 8.5K.
Or are you going the old school flat tappet route?

What kind of HP and Torque you looking for?????

Clayton


PS: I never should of sold my 91 Ford Pickup. I loved that 302 engine. (IMG:style_emoticons/default/burro.gif)

[messix]

I will remind my friends with Z06 Corvettes, They got burned by Chevy with a 400 HP truck engine... (IMG:style_emoticons/default/yappin.gif) (IMG:style_emoticons/default/hitfan[1].gif)

On the other hand.. You gunna use a later model 302 roller motor? As that would make the most sense to me. Especially with EFI if ya like the cosmetics and performance of EFI. The little fords can be a great platform for performance.

What kind of HP and Torque you looking for?????

Clayton


PS: I never should of sold my 91 Ford Pickup. I loved that 302 engine. (IMG:style_emoticons/default/burro.gif)

he's not gonna build a "fff"ford ya big dummy!

he's gonna build a high reving sbc 302 [4" bore x3" stroke.

the "spensive part is the crank [custom grind now], the valve train, the rods [gonna have to go with 4130 "H" beams], forged main caps w/splayed 4 bolt/stud, and no reason not to use aftermarket aluminum heads. 8500 rpm and 400 -500 hp easily done with $$$$$$!

[marks914]

I'm doing one right now as well.
Large journal 302 crank, 350 4 bolt block, modern valvetrain and heads.
It should fit the weight and gearing car better, even with the tall gears than the 305.
Hey driveability, where'd yo uget a large journal 3 inch stroke crank? I was just lucky.

Once you have the crank, the rest is standard 350 stuff. My engine builder saved me some dough by moving the wrist pin on a set of 327 pistons instead of using 302 units, saved about $300.
The other trick is to use L-99 5.94 inch rods and you can use 350 pistons.
Or use L99 crank and rods in a LT1 350 w/ 350 pistons block for a modern 302

Mark

[Crazyhippy]

I've driven a few 350ish HP 302 914's and they are FUN!!! Still have tq down low (not quite as much) and they just pull and pull and pull and then you shift.

If i was building a SBC i'd try to do a 350 the hard way... 327 crank in a 400 block. still spin 8k rpm but more displacement and more power. The Siameesed bores are a PITA, but do-able.

BJH

[Andyrew]

Sweet!!
I definately will be watching this....


Andrew

[drive-ability]

I have been talking to the engine builder, he's a corvette specialist(older ones) and the cost is (to me) quite high. He doesn't come cheep, I am looking at around 4,700 bucks just for the short block. That may be a bit steep but he will do it correctly. The trigger has not been pulled yet. I will have to think hard about this. I know I won't be happy with the car without that combo. I went to school with a guy who had a factory DZ, 302, running a huge cam and 12 to 1 CR. That engine ran incredible. In fact he kept it maintained so well (and babied it too) it lasted over 100k miles. Right now my engine and trans are out of the car and I am doing a lot of Little up grades to the engine compartment wiring, that will take some time. I hope to decide on the engine within a month, if not I will likely go with a G.M. 350 partial short block, maybe a ZZ4 lower end. In the mean time I am driving a 76 Fiat X19 with maybe 70 hp, I have to rev it to 5k between shifts to stay with traffic, 4200 rpm at 65 mph. (IMG:style_emoticons/default/driving.gif)

[Crazyhippy]

Can do alot better than a ZZ4 for the $$$
Want to be sure to use Alu heads, and a lil work makes the edelbrock's work pretty well for the $$.

You having a 930 box already means you dont have to go small displacement. you can build a 350 to turn 8500 rpm's but the extra tq is too much for the 901.

The 302 is a neat motor, but you dont need to limit yourself to keeping small displacement. Explain to your motor builder you want a high RPM motor, and are only moving 2500lbs. Let him build a motor from there (course we want to know what his plans are)

BJH

[dakotaewing]

I have been talking to the engine builder, he's a corvette specialist(older ones) and the cost is (to me) quite high. He doesn't come cheep, I am looking at around 4,700 bucks just for the short block. That may be a bit steep but he will do it correctly. The trigger has not been pulled yet. I will have to think hard about this. I know I won't be happy with the car without that combo. I went to school with a guy who had a factory DZ, 302, running a huge cam and 12 to 1 CR. That engine ran incredible. In fact he kept it maintained so well (and babied it too) it lasted over 100k miles. Right now my engine and trans are out of the car and I am doing a lot of Little up grades to the engine compartment wiring, that will take some time. I hope to decide on the engine within a month, if not I will likely go with a G.M. 350 partial short block, maybe a ZZ4 lower end. In the mean time I am driving a 76 Fiat X19 with maybe 70 hp, I have to rev it to 5k between shifts to stay with traffic, 4200 rpm at 65 mph. (IMG:style_emoticons/default/driving.gif)

I hope for that kind of money you are getting a brand new 3" forged crank -
I am not talking about an NOS DZ crank -
There are a few companies that are making them, and they run about $1500 -
Good luck with your project -

[wbergtho]

I'll be keeping my eye on this one.....Hmmm....8,500 RPM? That will sound fantastic!

[andys]

Did I miss something; I didn't see mention of him wanting to spin to 8500RPM. That will be an expensive valvetrain; if you want it to last that is.

Andy

[KELTY360]

Did I miss something; I didn't see mention of him wanting to spin to 8500RPM. That will be an expensive valvetrain; if you want it to last that is.

Andy

Check the thread title. (IMG:style_emoticons/default/cool_shades.gif)

[wbergtho]

Let's see....8500 RPM coupled to a 930 gearbox....that's about 220MPH in a vacuum....now add into the equation the aerodynamic drag CD and you have a car that could go very fast! I'm guesing it will be crazy fast in 1st and 2nd gear....then the drag starts to really pile up. I shift my LS6 @ 6800 RPM and can't break 60 mph in 1st....with my 930 box. You'll be able to do so.

[andys]

Did I miss something; I didn't see mention of him wanting to spin to 8500RPM. That will be an expensive valvetrain; if you want it to last that is.

Andy

Check the thread title. (IMG:style_emoticons/default/cool_shades.gif)

You're right; my bad. Kept re-reading the thread and paid no mind to it's title. Sorry, had a senior moment there!

Andys

PS: wbergtho is right on with the gearing comment. That 930 gear spread is well suited to a torquey motor. I vote you stay with a nice 327 or 350 and not worry about huge and expensive RPM. FWIW.

[byndbad914]

Driveability - I would be scared of a short block that was under $5K and meant to live at 8500rpm. I built a number of small block Chevy race engines including my own and can promise you I built either 3 or 4 302s (can't recall if we used a 400 block and spacers on one - I think I actually built one of the 302 cranks into a 400 block by getting fuzzy - about 6-8 yrs ago).

I did one for a "budget" and in the end I think the stock rods were the weak point and couldn't handle it even with ARP bolts, shotpeened and blah blah. 8500rpm is a LOT of rpm guys! Think of what it takes to make a NASCAR engine live at that rpm for a few hours of running (now they are above 9K but just a few years ago at 8500rpm those engines had serious guts).

And by "live at 8500" I mean put $$ in the crank, rods (really strong steel I-beam or H-beam, but H-beams can be heavy - mine were), pistons and valvetrain.

And wait until you have to change the chrome-silicon spring set each year if you really run it up to that rpm a few track days. Maintenance on an 8500rpm motor is not cheap as that will take a pretty serious cam.

If you want a 302 to live at 8500rpm, it is going to cost you some bucks frankly. I have about $10K in my destroked 400 (353 cubes with 327 crank - a combo I built a ton of for circle track motors and another member mentioned this combo earlier) and I only run it up just over 7300rpm and really don't have anything exotic - stock 400 block that I machined for splay-main 4-bolt caps 2-4, stock 327 steel crank, Eagle 6" H-beams, SRP off-the-shelf (OTS) flattops, Canfield 195cc heads (with serious port work now), cheap(er) Probe shaft-mount rockers, solid tappet Elgin cam that was $60, so forth. Nothing really that outstanding, tho' all the parts are right to spin to 8500rpm, but not live there. The cam won't get it to 8500rpm, but the other parts would go there a couple times (IMG:style_emoticons/default/biggrin.gif)

I built a DZ302 to shift between 8500-9000rpm for a 69 Z/28 the guy used for drag racing. Big roller cam, big heads (220cc IIRC), crower crank, ti valves on the intakes, Jesel shaft mount rocker arms, etc. The short block was definitely not cheaper than $5K - the Crower crank was about $1500. I think that was about a $15K carb to pan but it lived at that rpm no problem. I used aluminum rods in that one IIRC. That or another high rpm 302 I did for a Z/28 was a steel I-beam rod motor.

BTW, I think Eagle is making a 302 crank now, but if you are serious about 8500rpm, I don't know if I would trust the Eagle tho' I have built some serious motors with their cranks. By the time you find a stock crank and machine it, lightweight the counterweight, etc and do a heat treat of some sort, probably could just get a Crower crank or similar quality and pay the $1500-$2K.

I have $1100 in my 327 crank to get it down to 42lbs. The 302 crank is lighter to begin with, but to spin that rpm I would pendulum cut/bullnose and knife-edge/drill the rod journals and run a quality light steel I-beam rod and an OTS SRP piston. That = $$.

Not trying to rain on anyone's parade, but I can't tell you how many times I had guys come in wanting to build 302s that spin 8500rpm - which seems to be everyone's magic # for that combo, tho' really closer to 9-9500 is where that engine would work best based on rod/stroke ratios, etc.

Lastly, if you assume you want to drive this thing around town periodically, that cam won't make any real power below 6000rpm. My car is too obnoxious to drive with a big tappet cam that maxes the outputs between 5100-7300rpm. Below 3K it will lug the light 914 around the track no problem, but when it gets up to around 5K it takes off like a raped ape straight to 7300 when my shift light comes on.

FWIW.

[drive-ability]

(IMG:style_emoticons/default/icon8.gif) Well I chickened out (IMG:style_emoticons/default/drunk.gif) Looking at the cost was one factor but mostly I built this car to be a nice driver. For now I am going with a G.M. crate long block and use my heads and a different cam. This will cost under 2K and work perfect for everyday driving. I will however be sourcing the other parts for the 302 and maybe in a year or so it will be ready. You guys know and have said 8k is hard on a small block and can get expensive. Funny thing is my wife is all for it but I had to draw the line for now... (IMG:style_emoticons/default/icon8.gif) (IMG:style_emoticons/default/icon8.gif) (IMG:style_emoticons/default/icon8.gif) (IMG:style_emoticons/default/icon8.gif)

[Dr. Roger]

Let's see....8500 RPM coupled to a 930 gearbox....that's about 220MPH in a vacuum....now add into the equation the aerodynamic drag CD and you have a car that could go very fast! I'm guesing it will be crazy fast in 1st and 2nd gear....then the drag starts to really pile up. I shift my LS6 @ 6800 RPM and can't break 60 mph in 1st....with my 930 box. You'll be able to do so.

=-)

did u see that top gear episode where the bugatti did it's top speed of over 250MPH?

he said it took only 300HP to get to 150MPH but a total of 1,000HP to get it over 250MPH.

food for thought. =-)

[Twystd1]

302 Ford...

302 Chevy.

I biffed that one... HARD... LMAOAMyself....

Clayton

[byndbad914]

I think that is a good choice for now IMO and knowing what you have been looking for up to now which is a good, smooth riding streeter car.

Down the road a really badass combo is a 400 block and 350 crank (the big bore helps to unshroud the valves on a good aftermarket head and with the 3.48 stroke you can get a 6" rod in there and good rod/stroke ratio). Built a couple of those - one for another 69 Camaro drag car (built a lot of ripping small blocks for 69 Camaros!) With the 930 trans you could use a "big but streetable" hyd roller cam, shift just under 7K, the motor would sound fantastic, run forever and should be able to push 500HP on pump gas if built right. 377 cubes assuming .030" over 400 block. SRP has an OTS piston for that combo - go flattop and 11:1 and run 91 pump gas.

That would be the engine I would recommend for a street 914 with a 930 trans. The only reason to shorten the stroke is to spin it and that just isn't a "street" way of thinking. I almost built that for mine but I really like to spin 'em so I went short stroke. Streeter would have been 377 for that light car.

[Crazyhippy]

Let's see....8500 RPM coupled to a 930 gearbox....that's about 220MPH in a vacuum....now add into the equation the aerodynamic drag CD and you have a car that could go very fast! I'm guesing it will be crazy fast in 1st and 2nd gear....then the drag starts to really pile up. I shift my LS6 @ 6800 RPM and can't break 60 mph in 1st....with my 930 box. You'll be able to do so.

=-)

did u see that top gear episode where the bugatti did it's top speed of over 250MPH?

he said it took only 300HP to get to 150MPH but a total of 1,000HP to get it over 250MPH.

food for thought. =-)

914 aerodynamics @ 160 makes the back tires so light they spin instead of making you go faster (IMG:style_emoticons/default/headbang.gif) This was In Renegade's "peal" and no, Scott wasn't in the car (IMG:style_emoticons/default/happy11.gif) (IMG:style_emoticons/default/mueba.gif) REALLY scary feeling, you dont do anything fast from there.