A guide to building the lil guy. The Mighty 300

I've been following your progress as well Doc.

I have been pondering making a nailhead EFI intake for quite some time. When I do make one (once this project is done and the engine management is verified as viable), I was/am going to make it for a set of heads with the original intake flanges completely milled off much like the "Rotted Honda" heads from a while back. Then hopefully some forced induction after that.

May I make one suggestion though? I would not consider for a minute the intake spacers that some are suggesting. My and many others' experiences with that vendor have been full of broken promises and deadlines never reached. If you do go that route, be prepared for epic excuses and months of waiting.

 

I hear you,,,, no,,,, I am making my own flanges....I have a lot of things to overcome doing this thing.....but , my idea is this,,, make a manifold that looks somewhat like the factory iron one,,, and will just bolt on and work.... the only deviation that I am thinking about is a hot water manifold under the bottom of it to heat it up ... like buick did with the 300 manifold.... instead of exhaust heat that will eat the aluminum up....
I am leaning toward two manifolds, back to back , welded together in the center,,, and then there is the issue of all the fittings , bolt holes, ect. that have to be made and welded on ....but first I have to learn to tig weld aluminum.... but I can cut out and shape and fit and make patterns... ect...

 

I will be following your progress closely

 

Runners and bolt spacers:beer

 

Great progress!:beers2:

 

moving along at a snail's pace between work, waiting for materials to arrive, and the welder having time.

 

Dos anyone know what C/R youll get with a set of 3.8/350 pistons in a 300o No:

Theres been lots of talk about how to make them fit, but not how much gain or loss of compression.

 

depends on how many cc's the dome or dish of the piston, compression height of the piston (3.8 and 350s are slightly different)

 

Re: A

Thats what Im asking.

Dos anyone know the cc of the heads, and the ccs of the commonly availible pistons?

What CR are 10-1 350, 8.5-1 350 and 8.0-1 V6 pistons in a 300?

Say on a 10-1 350 piston in a 300 do the fewer CIs cancel out the smaller comp-chamber and bring you back to 10-1?



Im just saying that this would be some VERY VERY usefull info in a thread called A guide to building the lil guy. The Mighty 300

 

some intake progress...























Like a boss...:beer

 

Thats gonna be wild looking.... I am jealous,,, I wanna be able to tig weld that purty so bad.....:laugh: :laugh: Just bought my machine,,, gotta learn how to use it before I can finish my nailhead intake....lookin good... real good....:Brow: :Brow:

 

Very nice. That's gonna move some air, no doubt.

<Dos anyone know what C/R youll get with a set of 3.8/350 pistons in a 300o No:>

There are some real good CR calculators online where you just input the numbers. Also dynamic CR calculators.

JB

 

Thanks for the compliments guys, but all of the welding and a lot of the sheetmetal work is not my own. A friend of mine I went to high school with owns an automotive and fabrication shop up here. He has the sheetmetal brake, TIG welder, drop shear, and plasma cutter. I have the mill, lathe, and bandsaw. He does most of the sheetmetal and welding work, I do the machining.

We're making this come together, combining our abilities and resources. I come over to the shop and cut and sand bits, offer my vision, generally annoy and disrupt his day, he cuts and bends more bits, and welds it all together.

I traded him a car for his portion of the work on this and more; He's going to be making me an aluminum core support, and help in the turbo exhaust plumbing on the wagon as well. We'll see where the tab is after that.

I just realized I have a 350 block and these 300 heads... There's a possibility of making an intake for the TA heads on a 340/350... IF someone were interested and not in a huge hurry I can ask him if he's willing to go in together on building another... I think that any intake we make though will be either like this one with only the lower part of the plenum with a flat plate to mount carb(s) that wouldn't fit under a stock hood, OR this style EFI intake that would fit under a stock hood (This intake is less than 10" high from valley pan rail to top of plenum)

A couple updates from today's bit of work:

Crummy job I did cutting out the front bulkhead (hard to plasma cut with a broken index finger)


Top of the plenum formed

 

If you do build a 340/350 intake, just pay attention to the 5/7 pairing. You might want to separate those two runners a bit where they join the plenum.

JB

 

We were going to splay the runners on this intake as well, but noticed the bend of the runner in the head and decided that continuing that bend would be more detrimental than not evenly spacing the runner ports in the plenum.

I will have to take a closer look at the 350 heads when I get a chance.

Might offer 'um with a bolt-on upper plenum so one could have the choice of running carbs or EFI. Though, the throttle body flange in front would need a different solution.

 

It really does look good, and should work well. A 340 version of this intake would work well with the TA-Rover aluminum heads on a 350 short block. If you have a 340 or 350 block it might be worth mocking that up as I know there is at least one guy considering that build and this would only leave the cam to be sorted out, and that doesn't look like much of a problem.

JB

 

yes, i'd be intertested in a 300/rover topend for a 350 block
i'm in no real hurry but definatly interested

out of curiousity any reason you didnt build a cross flow intake?

 

Mike are you talking about one with tubes crossing over to separate plenums?

We went this route because it allowed the least complicated method of getting the longest runners possible whilst still under the stock air cleaner height. With the tapered runners it should provide a sort of venturi effect as well.

With the cross ram intake it would have needed two throttle bodies with associated plumbing and linkage, complicated runner routes, and trying to figure where to put the injectors and fuel rails with the plenums in the way.


I am interested in making more, but I need to wait a few weeks for my broken finger to finish healing.

 

Just need in to weld in the injector bungs and figure out a thermostat scheme...

 

Beautiful! Nice job!!:TU: