318 draw through build

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wardy said:
So all cylinder from the right bank blow exhaust gas into the front and rear exhaust ports on the left bank.... Where exhaust gas is also trying to get out?? And the turbo is only driven off the 2 centre cylinders on the left bank? Won't that just choke the engine to death like blocking the exhaust.

Excuse the ignorance but I've never seen a setup like this! I can clearly understand the draw through (cold side) but the exhaust has me baffled.. No pun intended
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This exhaust setup does look confusing... But the left bank and the right bank are joined and all exhaust gases exit via the 2 center left exhaust pipes through the turbo.
At first glance it does look like it would be restrictive but no more so than going through the turbo.
Bakerlite has Bohica2xo helping him and from what I've read of Bohica's posts, he is one clever guy.
 
scrappydoo said:
This exhaust setup does look confusing... But the left bank and the right bank are joined and all exhaust gases exit via the 2 center left exhaust pipes through the turbo.
At first glance it does look like it would be restrictive but no more so than going through the turbo.
Bakerlite has Bohica2xo helping him and from what I've read of Bohica's posts, he is one clever guy.
Click to expand...

the draw through on the intake makes sense to me

what baffles me is the the left and right join together at the bottom, but I only see about a 1 inch passage from the rear to the center ports and front one doesn't join; and has to blow into back pipe which in the end goes through that 1 inch opening

they should be like a double shorty header and exit bottom and top, bottom should cross to other side and top enters the turbo, what I see will not allow engine to run let alone build boost
 
66plyValiant said:
the draw through on the intake makes sense to me

what baffles me is the the left and right join together at the bottom, That's right and from there all exhasut gases exit the turbo
but I only see about a 1 inch passage from the rear to the center ports That's right
and front one doesn't join;Front and rear join where the right bank joins the left header
and has to blow into back pipe which in the end goes through that 1 inch opening No, it all goes out the center 2 left exhaust tubes and then through the turbo

they should be like a double shorty header and exit bottom and top, bottom should cross to other side and top enters the turbo, what I see will not allow engine to run let alone build boost
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I think you're overthinking it, all exhaust exits the turbo it just takes a few twist and turns to get there. Anyway that's how I see it.:thumbup:
 
scrappydoo said:
I think you're overthinking it, all exhaust exits the turbo it just takes a few twist and turns to get there. Anyway that's how I see it.:thumbup:
Click to expand...

if you have to send #2 exhaust fumes going through #8 pipe thats quite abit more then what it should have to and won't have time to clear before #2 hits again, having headers are supost to prevent that not make it worse
 
66plyValiant said:
the draw through on the intake makes sense to me

what baffles me is the the left and right join together at the bottom, but I only see about a 1 inch passage from the rear to the center ports and front one doesn't join; and has to blow into back pipe which in the end goes through that 1 inch opening

they should be like a double shorty header and exit bottom and top, bottom should cross to other side and top enters the turbo, what I see will not allow engine to run let alone build boost
Click to expand...

I agree with this.
 
66plyValiant said:
if you have to send #2 exhaust fumes going through #8 pipe thats quite abit more then what it should have to and won't have time to clear before #2 hits again, having headers are supost to prevent that not make it worse
Click to expand...

I think you need to forget header theory when dealing with a turbo as the turbo will be the biggest restriction in the exhaust, think of log headers versus tuned headers. tuned headers don't gain much over a log design when pushing through a turbo.
So cylinder #1 and #7 join up with #2,4,6,8 under the engine and then they all flow up to #3 and 5 and then out through the turbo.
 
scrappydoo said:
I think you need to forget header theory when dealing with a turbo as the turbo will be the biggest restriction in the exhaust, think of log headers versus tuned headers. tuned headers don't gain much over a log design when pushing through a turbo.
So cylinder #1 and #7 join up with #2,4,6,8 under the engine and then they all flow up to #3 and 5 and then out through the turbo.
Click to expand...

Correct, but in a conventional turbo setup each bank merges into a common point and into the turbo..

The way this is setup gas from cylinders 1 and 7 need to make their way into ports 2,4,6 and 8. Which are also trying to get their gas out. All the power to the people doing the work and I look forward to the progress.. But I don't see it working
 
scrappydoo said:
I think you need to forget header theory when dealing with a turbo as the turbo will be the biggest restriction in the exhaust, think of log headers versus tuned headers. tuned headers don't gain much over a log design when pushing through a turbo.
So cylinder #1 and #7 join up with #2,4,6,8 under the engine and then they all flow up to #3 and 5 and then out through the turbo.
Click to expand...


yes but # 3 and 5 pictured are only connected to the rest of the 6 cylinders with a 1" or less pipe, if your feeding 6 cylinders into a 1" pipe your bound to have problems

correct me if I don't see something I should because I really am trying to understand and not trying to flame anyone
 
moparfury123 said:
as you said there is no need for a for a blow through carb since it is not pressurized
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No need for a blow through carb, but it does need a boost referenced power valve instead of a vacuum referenced powervalve. Holley makes a carb with that port, or you can drill a standard Holley carb and add the port.

I run a draw through turbo on a 225 slant six.
 
66plyValiant said:
yes but # 3 and 5 pictured are only connected to the rest of the 6 cylinders with a 1" or less pipe, if your feeding 6 cylinders into a 1" pipe your bound to have problems

correct me if I don't see something I should because I really am trying to understand and not trying to flame anyone
Click to expand...

I'm not sure what size the header pipes are, they look to be 1 5/8" but the gases are flowing through both so you have 2x 1 5/8" pipes that all the other 6 cylinders are flowing through then meeting up with #3 and 5.
This approach certainly isn't the most efficient but for what Bakerlite is trying to acheive it will certainly have enough flow.
 
I'm confused as to how all cylinders besides #3 and #5 can get their gasses to the turbo? Am I overlooking something here?

From what it looks like you will only be feeding the turbo from 2 cylinders and the rest will be fighting each other
 
wardy said:
I'm confused as to how all cylinders besides #3 and #5 can get their gasses to the turbo? Am I overlooking something here?

From what it looks like you will only be feeding the turbo from 2 cylinders and the rest will be fighting each other
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Exhaust gases will flow to the point of least resistance which is the turbo outlet, not the other cylinders.
The exhaust gases might be "crashing" into each other but they'll get over it and exit out the turbo.
Your setup wardy is the way you want to be doing it, but for what bakerlite is trying to acheive this exhaust will work fine.
 
scrappydoo said:
Exhaust gases will flow to the point of least resistance which is the turbo outlet, not the other cylinders.
The exhaust gases might be "crashing" into each other but they'll get over it and exit out the turbo.
Your setup wardy is the way you want to be doing it, but for what bakerlite is trying to acheive this exhaust will work fine.
Click to expand...

So all gasses need to find their way into #3 and #5 to exit the turbo? I still can't grasp it haha.

I'm looking forward to the updates though
 
Hi all, Correct, all the cylinders feed the turbo. Both exhaust pipes from cylinders 3 and 5 have been opened up internally and are , when joined this way, larger than the turbo exhaust feed pipe. Notice how the turbo feed pipe is right above the collector?? That means all the gasses from the RH bank cross under the engine, run up through the LH collector , straight into the turbo pipe. The only cylinder gasses which will have to make a 90 degree turn will be cylinders 1 and 7, and that's no problem. The turbo is the biggest restriction in the exhaust system, on this project.I will be updating this project soon. I'm just a little busy with the body work that this engine is going in to.
 
scrappydoo said:
This exhaust setup does look confusing... But the left bank and the right bank are joined and all exhaust gases exit via the 2 center left exhaust pipes through the turbo.
At first glance it does look like it would be restrictive but no more so than going through the turbo.
Bakerlite has Bohica2xo helping him and from what I've read of Bohica's posts, he is one clever guy.
Click to expand...

Thanks Scrappy!

Here is the advertising for the martin system as I designed it in 1978:

Martin.jpg


Martin1.jpg


And a pic of one of the later production kits - I found this one for sale on e-bay a couple of years ago:

Martin2.jpg


Kind of fun to see them still in the market 30 years later. The system works well when you are using a carburetor.

The exhaust all goes through the hot side. What bakerlite is doing is replicating the LA system I built that never made it to production. Test vehicle was to be a 1979 Cordoba...

We used Quadrajets & Thermoquads. With the holley power valve, you can either ignore it or remove it. The secondaries should be rich, like 11.5:1 on boost. Primaries can be fairly rich too. The draw through atomizes fuel very well.

B.
 
If you are gonna spin an air motor fast an hard what works better? High pressure through "Small" opening or high volume through a "large" opening. I've always used a Rather large tank of highly compressed air connected to a tiny little hose and it powers my air tools just fine! LOL. Seems a lot of you are looking at it like a flow through engine rather than an air compressor fed POWER tool! Although, an outlet for "over compressed" air may be helpful? It's all gonna exit 2 1/2 or 3 in pipe I imagine with flow through muffler(s). I think it will work just fine. Keep up the good work and keep the posts coming!

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