I need to do some more sanding before I start painting but here's part of my winter project done. I yanked off that tall 6" cowl scoop and molded in a 2-1/2" cowl scoop. I then attached a very short bolt on aero scoop on top of it.

The induction system has also changed. The old Weiand tunnel ram and carbs are off and an Edelbrock 2R tunnel ram with dual 4.1" toilets is now on the engine. No air filters and with the hood closed, the aero scoop is about 2" away from the top of the front toilet. I have a plug for the scoop to keep the dirt out and I'll fabricate some covers to put over the toilets to keep dirt out when the hood is open or when in transit.

For those of you who don't know, a toilet is just a throttle body for a mechanical injection system. Each one of these toilets flow 1800 CFM.

 

thats an awesome project
i really like the hood.

 

I'm still not sure why a single plane single dominator wouldn't go just as fast? Which would also allow you to run a smaller hood as well.

 

Dual carb systems only make a little more power than a single system. The advantage is consistency as conditions change and a flatter power curve. A dual system needs a big change in the weather for performance to change. The vacuum signal to the carbs is also different. You actually get better throttle response from 8 small butterflies than 4 large ones with carbs. Each of those toilets is one big butterfly but they don't need a vacuum system to work.

There's also the WOW factor of having a tunnel ram. Instead of the dual toilet system, I'd rather have an Enderle hat system. A bird catcher would look nice sitting on top of that tunnel ram. But then it would also look good sitting on top of a 10-71 blower too. Too bad I run too much compression to install a blower on this engine.

Another nice system would be a sheet metal tunnel ram with a set of split dominators on top of it.

That tunnel ram with the toilets is also a lot lighter than the other tunnel ram with the carbs.

 

how much compression are you running?
and how much power would you get with this setup then your last setup you had?

 

I was always under the impression that dual carbs and tunnel ram is about as inconsistent as you could get compared to a single plane intake and a single carb, or is that just bad info?

 

i hope that isnt true. i kinda want to add a tunnel ram to my car

 

i wouldn't put a tunnel ram on a low compression small cubic inch 305 like yours ever. It would be a total dog. You need to think 4500+rpms for start of the power band, etc etc

 

This engine is around 13:1 compression and run on alcohol.

Problems with a dual system are usually from bad tuning. Both carbs need to be exactly the same. I never had any issues that I know of with my carb settings.

I have no idea how much power the new induction system will give me. I really expect it to run exactly the same but if it goes faster, that will be a bonus.

As I already mentioned, carbs need a vacuum signal to operate. Launching at WOT off the transbrake means there isn't much of a signal so there isn't much of a fuel curve. As the car goes down track and hits peak rpm, the amount of fuel the engine needs actually decreases because it isn't under as much load.

With the toilet system, it's a simple mechanical injection system. As the throttle opens, the butterflies open to provide air and the barrel valve opens to provide fuel instantly. There's no vacuum signal required to get fuel into the engine so throttle response is even better. If the engine gets too much fuel at the top end, a high speed bypass valve can be installed. Fuel is provided by a belt driven pump. The faster the engine spins, the more fuel is pumped into the engine. It doesn't operate at a constant pressure like a carb.

My camshaft starts to build power at 4500 rpm. My converter stalls just under 6000 rpm. I go through the traps around 7400 rpm.

 

i like your engine setup
is it pure 100% alchol? or is it like E85 or some type of mixture??

i really dig your hood tho haha. is it alot of fab work in the hood? i guess its fairly easy to work on a fiberglass hood then a steel hood. by the way. im eather thinking of getting a tunnel ram intake kit and comes with 2 600 cfm carbs and fuel lines. the works.
anyways im woundering how much will it stick above the stock hood? ill be making a whole ofcouse but im really not to sure how high it will stick out. i dont want it to stick out to high or it will jsut goofy.
if it sticks to high im probably going to get a victor jr. style intake insted. i dont mind making a whole hood.

do you know how high its sticking out from your car? from the photos they dont look overly high.

 

it will stick out a ton and as already stated NOT a good idea for a low compression 305.

 

Hood looks much better than the previous set up....

alcohol goes best with blowers!!! nothing like that sound and smell

 

You'll love the consistency with the toilets as well, we ran them on the S/C car. We could run the whole day staing within .010 of our number. BTW, the hood is looking good.

 

I run 100% methanol. E85 is 85% ethanol.

A 305 would probably need dual 450's on a tunnel ram. You're going to lose a lot of bottom end torque which is what you need for street use.

You would need a scoop higher than what I now have because you'll need to run some sort of air filter system. Either that or you just have a hole cut in the hood with the carbs and filters poking through.

The picture in my sig shows the 6" cowl with the air filters above it.

 

theres no way im putting tunnel ram on a 305. i got a 383 build going on right now. it was for that.

ill check out your website of your car

where do you get 100% methanol?

 

tunnel ram on a street car = turd.

stephen, have you ever ran that car in a lower altitude? it would be interesting to see how much you pick up running the car around sea level.

 

oh jeez lol.

 

OK, 99.96% or whatever it is. I buy my methanol by the barrel from a local industrial supply warehouse. If it was an emergency situation and I needed fuel, I could go to Home Depot and buy all their methyl hydrate. It's the same thing. I could stop at any truck stop and pick up air brake antifreeze, same thing. When I buy a barrel, I pick up a bottle of top lube from the local speed shop to pour into it.

Not counting warm ups, moving the car on and off the trailer etc, I burn about 5 gallons of alcohol in three 1/4 mile passes. That's roughly 6 miles on the car. Only a 1/4 mile of a run is at WOT. The rest is coasting down to the end of the track and driving back up the return road to the pits. Each pass is about 2 miles.

I've never been to a lower altitude track since converting to alcohol. Theoretically, at sea level, the car should run in the 9.1's. The next 2 closest tracks are about 3 hours away. Both are around 1000 feet lower than here. One is IHRA like our local track. The other is NHRA and I don't have the NHRA qualifications to run quicker than 10.0. Under IHRA rules, I can run as quick as 9.0.

 

oh wow fuel guzzler. but i guess it worth it if your caar can do 9s with out a poweradder.

 

LOL, power takes alot of fuel, and couple that with running alky you have to use twice as much when compared to gasoline...but in the summer heat it's alot more consistant overall, and instead of watching the DA for changes you only have to watch humidty, which is alky's arch nemisis

Hood looks sooo much better than the old version, good job/good call Stephen.

 

Looks much better. I would like to see a good sheet metal intake with the split dom. and alcohol. And that hood of yours steal or glass?

 

The hood is a factory fiberglass hood. That's the main reason for having a long cowl scoop. It covers the factory indents in the hood. This is the third or fourth one I've experimented with over the years. I pick them up whenever I can but haven't found one in a long time.

An lightweight aftermarket lift off fiberglass hood would be nice but that would mean needing a pit crew to help lift the hood off as it's so big.

 

sounds like you need to make some friends, lol!

hood looks much better, kinda wished you'd kept that car a small tire car, but with the consistancy of a big tire car, i see why you did it.

 

hey stephen,any tips on changing the scoop? i have a 2" cowl and i have thought of cutting it out and glassing in a 4".

 

Find another hood. My 6" cowl was bolted on making it easy to remove. The 2-1/2" scoop isn't as wide and some bondo easily filled in the old holes.

 

Hood is almost done. I'm going to shoot at least one more coat on it before laying out the flames. Most of the rest of the car is now sanded. Without any decals on the car, it looks naked. The gloss black was hard to photograph before. This flat black should be even worse. It's going to look mean

 

How tall is the aero scoop, looking good sofar cant wait to c the finished project.

 

The cowl scoop is 2-1/2" tall. The aero scoop is 4-3/4" tall.

 

Great looking hood Steve, I bet it will perform for you as well!!
You're gettig pretty good at that "body shop" stuff!!

 

Not really. Flat black hides a lot of defects. If you run your hand across the hood or at the transition area where the scoop joins the hood, you would feel that it's not perfect.

I finished sanding the hood and car with 150 grit sandpaper before shooting the paint with rattle cans. 150 is still course. It you want a good smooth finish, you finish off with 320 grit or finer.

I was never after a show car finish so what I'm doing is good enough. More of a rat rod finish.

I finally got the flames masked off and shot a white base coat last night. I'll probably get the rest of the color sprayed this weekend. Rattle can flame paint job but if I didn't tell you that, you probably wouldn't know. I airbrushed flames on my old Harley back in the early 90's but the surface area on the tank and fenders is a lot less than a car. Once I peel off the masking tape to see how it looks, I'll decide to keep the flames or sand them down and paint it all flat black. If I keep the flames, it will probably take me a few days just to pinstripe them.

It's a dual layer flame job. Traditional yellow, orange, red flames but instead of having the front of the car white or yellow, a second layer of flames using the base color starts at the front to go over the real flames. Took a bit to figure out a good pattern and layout. It's not 100% symmetrical from side to side. Pinstriping a black flame on a black background should be interesting.

 

You're a genuine geneius!!! I hope you won't get too upset if I callously "borrow"/steal your hood scoop idea...I have a tunnel rammed small block I need to hide under a scoop.. But I want to modify it a little. Make the aero scoop a shaker. Attached to the carbs and poke-in' up thru the cowl hood about 3/4s the way thru. Should be cool all a shaken an' a quiverin' at idle.
I've been scratchin my head for over a month on this.

 

I would have loved to attach an aero scoop to the engine. It would have been a lot easier. They're not that hard to attach to the engine. Just look at just about any dragster. It just wouldn't work with a hood that still opens like normal. A scoop that bolts to the engine is designed for a lift off, lightweight hood that's normally held on with Dzus fasteners.

First of all, my hood is a factory fiberglass hood and is still heavy. I would need a pit crew to help lift off the hood and with the fuel cell under the hood, it has to open after ever run. If I bought an aftermarket flat hood, a project like that would work. I bought the short aero scoop and cowl scoop off Ebay retailers. A lot cheaper than Harwood products and a better selection.

My engine doesn't shake. Using a front motor plate, the engine is solid to the frame rails. Don't forget, my hood style just covers the induction system. There's no room for air filters. As stated above, I have a plug for the scoop to keep the dirt out and I picked up some air cleaner spacers from TBI GM trucks to make as covers to put over the toilets while in transit or when the hood is open. I don't have the room for the plastic covers offered by Holley or Moroso. Those are tall and designed to fit over a choke horn.

I briefly had an aeroscoop on my 6" cowl. It was an old aeroscoop that I cut down and grafted to the top of the cowl. It lasted a couple of races then my fiberglassing let go around the 1000 foot mark and 130+ mph. It was cut down enough to cover the filters poking through the 6" cowl. Something like this on a shorter cowl would look real good. the smaller aero scoop I now use is considered a bolt on. There's a flange around the inside opening to attach it to the hood. No fiberglassing required. The main reason I had to put the aero scoop on this hood is that my toilets don't have a bridge to use an air filter. You can't have an open system like that on the track. The carbs must be covered by some sort of hoop/scoop or filters. I suppose I could have fabricated some bridges but I thought the aero scoop would look better.

Here's what the old scoop used to look like back at the beginning of the 2007 season.

 

Bwahahaha! Just finished the pin striping. Not perfect but looks good in the pictures

Flames didn't come out exactly the way I wanted but they're good enough to catch attention to the car.

 

haha very nice, should catch some attention. This hood looks 100x's better than the other one, but I wonder if you just put a taller scoop on a factory fiberglass hood would it still accomplish the same thing, rather than this half in half combo.

 

For many years I had a normal scoop on the hood. When grafting onto a factory fiberglass hood, you need some way to fill in the indents in the hood. I used a lot of fiberglass and bondo to fill in the area in front of the scoop. It started cracking shortly after that and I never bothered to fix it. The crack never spread so I wasn't too worried about it. All the extra bondo made the hood very heavy. The flames on the scoop were decals. I have even older pictures with very few decals on the car but most were taken before digital cameras were available and they are scanned pics.

To get away from finding a way to fill the indents, a long cowl scoop does the job very well.