OK, I'm not stupid but I have been out of the engine building thing for quite a while and this will be my first 302 build. I have a stock 79 302 from a truck with around 10,000 miles on a rebuild. I am looking to get 300 horses from this engine. I don't want it to be to radical just a weekend cruiser with a pretty good lopey idle. I need some one to provide me with a parts combination that will get me this HP rating, also what are the best heads to look for that can be found in the junk yard or used. I need to keep cost to a minimum, I'm funding two projects. I need carb, intake, cam and head combination info. Thanks for any help.
3310 Holley Wieand X-Cellerator LT Headers 270H Comp cam 71-73 351w heads I highly recommend doing some home porting on the heads along with screw in studs, plates, hardened pushrods, and roller rockers. Use the springs in the cam kit. You can also use Chevy valves in these heads, but if you go to wild with the heads, you will get close to the price of aftermarket heads with parts and machine work. Not equal to, but close. Use flat top pistons and a mandrel bent dual exhaust. You will find this combo will work best with 3.40 to 4.11 gears. If you are running a C4, a converter will add to performance, but is NOT manditory. Any larger a cam, then the converter will be manditory just to idle in gear. This cam is a single pattern and will have a mild and rythmic lope. If you want a rough lope, without getting to wild with the cam, then you can use a dual pattern cam. They tend to idle more erracticly even when they average the same duration. That is what will shake your car at lights. Comp makes dual pattern cams under the XE brand. Look for one with duration @ .050" less than 224 on the exhaust side. The intake will be lower. You need to keep it reasonable for this combo and for a stock converter. You go to wild and you will need more head, exhaust, and gear to get the best from it. Good luck Dave
The options are plenty and up to your own finances. My thoughts on it would be to use early 351 heads and a RPM manifold with Holley 650 vacumm secondaries for street use. A cam that I used and got good results with was an Erson hydraulic, with 286 duration and .514 lift. Installed at 4 degree's advanced, duraspark ign. and good coil along with Hedman long tube headers and flowmaster mufflers. Speed Pro flat top pistons with four valve reliefs. Block should be decked and the bore a bit larger oversize by about a .001 to .002. 2400 to 2600 stall convertor and a 4.11 gear in the back. Don't know if it will produce 300hp but mine ran like a scalded dog and at red lights the rumpity rump scared off a lot of show off's. The C4 had a mild shift kit installed and a trans cooler. You could also go roller like the E303 cam and GT40 heads too. Lots of other ways too, along with roller rockers and stuff like that. Going to have to get some sticky tires and a posi to take advantage of the mods. There are other block mod's and some ign changes that can be done but then all my secrets would be out. he he he.
Thanks guys, nice to have a few people around that have been there and know what to expect........do you think I can get by with the recent rebuild on this motor (10,000 miles) or start from scratch. It has 20 over pistons flat top TRW with valve reliefs but every thing else is unknown.
I would take a compression or leak down test to check rings etc. Would also remove the pan and check a bearing or two, change the oil pump to a Mellings high volume and make sure the pickup screen is clear. Using a dial indicator or feeler gage, check the end play on the crankshaft, should be around .004 to .008. Look at the cylinder walls for scoring and such. If you are satisfied go for it and put in the cam and whatever heads you choose, be sure and clay the piston and check for adequate valve clearance. If I was to do it(have done many just as described) would take a little more time and effort and tear it clear down and clean and measure and rering it etc. Might even change the main and rod bolts to ARP's too, but thats just me and have had some good luck with doing it the easy way and let her go at that. Had a fellow stock car driver back in the 60's who got a 283 Cheby engine out of the junkyard, with120,000 mi on it. Took the lifters out removed the innards to made solids out of them and installed them on a GM 29.00 cam of that era. Turned that puppy 7500rpm's for many races and won a lot of them. Just goes to show you that sometimes you can luck out and get by with not so expensive equipt. I am running a 302 in my drag car now that has a very worn block and used pistons and "rings" that was put together to get through the season, only ran a tenth slower than the high dollar 331 I had the misfortune of grenading because of a faulty oil pump(tried a different brand in it) Will always use Mellings as I have in the past, from now on. Got two more races this weekend and then will put another 331 back in for next year. Just for info, my sponsor and sideline business is"BackYard Motorsports" Get the picture? Kind of fits this old guy. One more thing in this loooooong post, the great Bob Glidden very rarely built his engines on a stand. Most were assembled on the floor with his son, and we all know how they ran.
Buy a used roller motor for 300-500. Sell all the fuelie stuff to get around 50-100 back. Mild cleanup on the heads removing the EGR hump. Buy a performer RPM air gap or similar intake, 600 holley. Boom, 300 horses for less than $1000 bux. AC
The induction used depends on where you want 300 hp. Rear wheels or flywheel? Generally speaking, 300 fwhp is about 240 rwhp, 375 fwhp is about 300 rwhp. It's a big difference. Dave
Good point ratio. A performer RPM may not put the power where he wants it. There could be better choices especially with a low stall auto. Also good point on the FWHP vs RWHP. 300RWHP is not as easy a number to hit as people make it out to be. AC
302 wasn't there a recent article in hot rod or car craft about a bone stock 5.0 roller with AFR heads, 4bl intake and carb with long tube headers that made 400HP. I think it was a stock cam with slightly higher ratio rocker arms?
I see you like that artical. Elliot i see you like that artical to i was wondering the same how is it stock when the changes that had been made lol. did the mean bone stock with mods, and i think if im not wrong. they tell you for like 6000 or 7000 you can have that 400hp lol. Someone with the right mind and know how of doing it could have it for about 900 maybe less.
I read the article....I was just under the impression they was talking about the bottom end being stock. Hell, anymore the only way some engines are considered modified is if its stroked or poked! I also, agree that if someone sells/builds a 400hp motor for 6 or 7 grand....... well maybe a all motor/pump gas car? Never tried to get 400 on pump gas....not sure how much that would cost? Maybe their price is so high cause they factor in the cost to run their suppliers advertisement in their magazine........it must get put in the bill as well
Yeah must be something. Yeah it must be something like that. But think about the money you would spend on spark plugs for it. to remove the heat from the chambers.
