Full race 300 ???'s.

[MUDICE1970]

I've been tinkering with the Idea of a full race 300 and I've got a lot of questions. For those of you who have done this how much HP is possible (with no power adders) with the design of the head. I've need to be bumping the 500 HP range to be competitive in what I want to do. The competion are all over 400 HP in lighter vehicles with better weight transfer so I'm at a disadvantage right off the bat. Some of my ?'s are How much HP can the block and stock rods stand? Is anybody running 240 rods in the 300 ? Are they as strong as the 300 rods ? Is there any HP gain with the longer rod? Does anyone have any flow numbers of a head that has been ported to the max. I've got a lot more questions but these will tell me if I can even get into the ball game and then I can go from there. Thanks for the help. Later Vick

 

[80broncoman]

I have no idea about flow numbers. The stock block,crank, and rods will hold much more HP than the stock non-crossflow head will allow.
You find a lot of info by using the search button on this site.
Look close at any input from French Town Flyer AKA "FTF"
He has gotten more HP out of 300s than anyone here.

 

[StrangeRanger]

IIRC, he's right in the 500 HP range with his altered.

 

[Mustang Boy]

i think i remember seeing someone selling a 500+hp 300 in the for sale section a couple of months ago so i know its possible and Azcoupe(admin for this forum and owner of www.classicinlines.com ) is in the developing stages of making an aluminum head for the big six and there is a sticky about it in the big six section. this will help the flow issues of using a stock head

 

[Thad]

You said some thing about weight transfer. That can be changed, totally different science than engine building.

At one time sixes were the choice for certain "Gas" classes. Allowed engine set back was 25% of wheel base measured from center of front spindle to first spark plug. A six would have two cylinder and the weight thereof past where an V-8 or 4 bangers would end. This moves clutch and trans and their weight back toward the rear wheels. Say +/- 10 -11" back.

In a light chassis race car that is a bunch.

 

[MUDICE1970]

What I'm looking at is mud racing. To run competive in the 4/6 cylinder class my only option is the 1st generation Bronco. It is the only thing that is the same width as the small trucks. ( You need to stay the same width so you don't have to cut a new set of ruts every time you go through the pit ) There are 4or5 Toyotas and a couple S-10 Blazers that run real strong. The Toys are allowed to use a turbo that they won't let us run on a Ranger/Bronco II and the S-10's got all out 4.3's. According to the rules I've got to run a factory combination but I think I can get by with a 300 in the 1ST gen Bronco. I've got to leave the engine in the stock location and it has to be street legal. I can get rid of the heater box and some other things but it has to have all lights, a driver side wiper, and exhaust to at least the rear axle. Were susposed to run a stock suspension but I can get away with some changes to get it to hook and launch better as long as it is fairly stock looking. As far as the cross-flow head I think it's out of the question, I don't think I could ever sneek that past tech. I've also got to run a cooling system so that probably lessens my porting a little but I plan on running alcohol so that might make a little of that back up. I'll try the search function and see what I can find. Thanks for the help. Later Vick

 

[StrangeRanger]

The 300 would be an EXTREMELY tight fit in a Gen I Bronco. The engine is huge by comparison to the stock Falcon six. It would stick out like the proverbial sore thumb. A 250 on the other hand is very nearly a bolt-in other than the requirement for a custom oil pan. It would take someone who knew about Falcon sixes to spot the difference. I do not think you could pull 2 HP/CID out of a 250 though.

 

[82F100]

Mudice, can you give us some more specifics on the class guidlines for the class you want to run?What type of racing Mud, sand, or pavement?Remeber a early bronco has a short wheelbase and that should be a consideration.As for the 250 it might be a better choice Does10's is reaching near the 500hp at the flywheel with a cast Oz head and turbo.

 

[Does10s]

Does10's is reaching near the 500hp at the flywheel with a cast Oz head and turbo.

Come on Rich.....we're only making a little over 400hp at the flywheel.

I'll let you know when we reach 500!

Will

 

[MUDICE1970]

This is mud racing. This past year the pits ranged anywhere from 4" to 3' deep. The 4/6 cylinder class rules say: Any size DOT tires, Body Frame and Drive must be of the same make, No aftermarket blocks or heads, Factory type suspensions (lifts and traction bars OK), and you have to keep the truck street legal. Lights, at least a driver side wiper, and exhaust to a least the rear axle. As long as the truck is fairly close to the way it came from the factory there isn't any static. Like staying with the inline-6 and not a V-6 in the GEN 1 Bronco. They have got pretty flexible sence they are letting the Toy's run the chargers. ( Nobody can catch them so there's nobody to complain )
What my thoughts were on my build, I'm using my experence with FE's and the work I've done with a buddy of mine on his small block Chevy's, is a .060 over block with 240 rods and custom pistons with around 14:1 compression ratio. Port the head for all I can get and put the biggest valves in it that I can shoe horn in there, with all the cam the head will flow. In the FE world, I'm quessing it is the same with all engines, if I can get the head to flow 250 on the intake and around 220 exhaust I can get the HP I'm looking for but if it won't flow that then I'm just beating a dead horse. Thanks for the help, Later Vick.

 

[80broncoman]

If u cant move the engine back do the next best thing :
Move the front axle forward! By hacking the fenders this can be hidden some. Or even cutting and make the fenders longer will hide it even better.
Just don't think you are gona move it 18 inchs and hide it, that is just too much.

 

[82F100]

Does10's, our little calculator on the website says 450-454HP depending on which formula you use, So I'm off 50 hp( at the flywheel)LOL

 

[lyonsy]

hey
ok so rule is visually standerd.
can you do what ever you want to the engine?
could you for instance cut the top out of the intake port and weld a section in.
this is what the rally guys do to the 2L pinto for rallying works pretty well to.
can you run alchole/methnol?
could you possible turbo a smaller engine like a 3L?
drift

 

[MUDICE1970]

I was planning on pushing the enging as close to the firewall as I can. (I think as tight as the 300 is gonna be in there that won't be too noticable) I'm gonna run R-85/15 Buckshots (37" tall) on the front with probably 4" of lift, so I've got to cut the fenders a bunch and my intensions were too try to slip the axle forward an inch or two (SHHHHHH don't tell anybody) and with all the cut in the fenders it shouldn't be noticable. I'm gonna run 38.5-11.00 Boggers on the rear with 2" of lift. With the combination of everything I've got planned to do it will help my hooking but I think (I could be wrong) the V-6 S-10's and 4-banger Toys will have better weight transfer just because the engines are so much shorter, but that is just a guess. As far as cutting the intake port were you talking about making the port taller to increase flow or did I miss something. Thanks for the input, Later Vick.

 

[MUDICE1970]

OK I just read the rest of your post. No turbo because it didn't come from the factory with one. I'm pretty much stuck with a Ford inline six with no power adders. I think I can sneek and run alcohol but I won't swear to it. Later Vick

 

[lyonsy]

hey
yep cut the top out and weld an extra section in to make the port larger will lose down low but up high will become a monster.
find ouy if you can run methnol if you can there is around a 100hp gainto be had when done properly
drift

 

[goinbroke2]

Cut the top? How about cut the bottom of the intake and add a section and then it will be hidden unless someone looks closely?

 

[6pack]

450HP is achievable with a stock head. About 290cfm is max for a cast head. A full roller 300 with webers, 3-2barrels or FI should make 400+. I have a some HP 300 stuff if interested.