Building a fresh 360ci engine for mileage & power

Propane, Butane, LPG, GPL, C3H8, C4H10
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kikkegek
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Re: Building a fresh 360ci engine for mileage & power

Post by kikkegek » Sat Apr 28, 2018 2:21 am

as far as the divider plate. I have heard that TBI systems are allmost impossible to tune without a gap in the divider plate. Port injection wont mind and I guess carb wont either. There is a video on Engine Masters where they dealt with it

they say something about it in this video at about 7:50min

[youtube]https://www.youtube.com/watch?v=2sQJPZYSoUI[/youtube]
daily: 1974 GMC 25HUNDRED Suburban - fresh rebuild 350 small block - TH350-NP203 - 4.1 end gears - IMPCO425 mixer - IMPCO model E vaporizer
project: 1977 GMC C15 Suburban - 454 big block - TH400 - gasoline
sold: 1986 Chevrolet Suburban K20 Silverado


storm
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Re: Building a fresh 360ci engine for mileage & power

Post by storm » Sat Apr 28, 2018 3:31 am

Try not to think about the manifold from a liquid fuel perspective. Liquid fuels, and the Engine Masters video is a good example if this, pool (or puddle) and cause issues with drivability. The issue in that video is the orientation of the injectors and how the liquid fuel flows into the manifold air stream. Removing a plenum divider gave the fuel more opportunity to mix with the air stream instead of slamming straight into the plenum wall.

LPG as you know is already a gas so it doesn't suffer from the same problems. I think it would be a worthwhile experiment but remember if the experiment doesn't work it is hard to put material back into the manifold once it is taken out. If it were me I would probably use an open carb spacer and see if that makes any difference.
Every job is a self-portrait of the person who did it. Autograph your work with excellence.

Fuel flow requirements calculations viewtopic.php?f=5&t=1638

BigBlockMopar
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Re: Building a fresh 360ci engine for mileage & power

Post by BigBlockMopar » Sat Apr 28, 2018 3:58 pm

The internet is 'full' of tips and tricks of modifications to get gasoline to vaporize or follow the airflow better, but hardly anything is to be found helpful for propane.

Trying an open spacer would be nice and simple to do during a dynosession where the hood can be left partly open and clearance won't be an issue.
https://www.bigblockmopar.com
'73 Dodge Dart - 360ci - 11.3:1cr
MegaSquirt + HEI 7-pin timing control - Edelbrock AirGap - Cold Air Intake
IMPCO E / 425 mixer - A518 OD-trans - 3.55 gears - 225/50/17" tires.

storm
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Re: Building a fresh 360ci engine for mileage & power

Post by storm » Sat Apr 28, 2018 6:30 pm

BigBlockMopar wrote:
Sat Apr 28, 2018 3:58 pm
The internet is 'full' of tips and tricks of modifications to get gasoline to vaporize or follow the airflow better, but hardly anything is to be found helpful for propane.
That's the big problem with the internet, everyone has an opinion and is willing to post it but very few have done real verifiable testing that can show whether something is worthwhile or not.
BigBlockMopar wrote:
Sat Apr 28, 2018 3:58 pm
Trying an open spacer would be nice and simple to do during a dynosession where the hood can be left partly open and clearance won't be an issue.
Do 3 tests. The 1st with the car as it is (i.e. no spacer), the 2nd with a divided spacer, and the 3rd with an open spacer. That way you'll be able to see if a spacer has any effect compared to no spacer and you'll also be able to compare open vs divided spacer.

I'd suggest the spacer won't make much difference (<1%) compared to no spacer, and the divided spacer will be about 1 or 2% better than the open spacer due to more velocity. I may be totally wrong but testing is the only way to find out.
Every job is a self-portrait of the person who did it. Autograph your work with excellence.

Fuel flow requirements calculations viewtopic.php?f=5&t=1638

BigBlockMopar
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Re: Building a fresh 360ci engine for mileage & power

Post by BigBlockMopar » Fri May 04, 2018 6:27 pm

Took the week off and have been busy with the engine swap since the LAST 4 DAYS already!
Doing an engine swap in a Mopar A-body car with smallblock and headers... NEVER AGAIN!

Finally had the engine running in the car today for awhile, until I noticed an oil leak coming from the angled oilfilter housing, which OFCOURSE is pretty much unreachable because of 4 header tubes blocking just about all access to it.
https://www.bigblockmopar.com
'73 Dodge Dart - 360ci - 11.3:1cr
MegaSquirt + HEI 7-pin timing control - Edelbrock AirGap - Cold Air Intake
IMPCO E / 425 mixer - A518 OD-trans - 3.55 gears - 225/50/17" tires.

gottago
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Re: Building a fresh 360ci engine for mileage & power

Post by gottago » Fri May 04, 2018 8:51 pm

Ohh the joys! Can you get an adapter to reposition the oil filter? Always a few little glitches to work out but hey your almost there.

storm
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Re: Building a fresh 360ci engine for mileage & power

Post by storm » Fri May 04, 2018 10:27 pm

There is always 1 or 2 teething problems with these types of things, it's a pity you have an oil leak in such an inaccessible spot though.
Any pics of the engine in place.
Every job is a self-portrait of the person who did it. Autograph your work with excellence.

Fuel flow requirements calculations viewtopic.php?f=5&t=1638

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kikkegek
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Re: Building a fresh 360ci engine for mileage & power

Post by kikkegek » Sat May 05, 2018 3:21 am

oh damnit, that sucks Herman! :cry:

My last two engine installs were a pain in the ass too. I know the feeling.

But yes, we'd love to see the engine installed!
daily: 1974 GMC 25HUNDRED Suburban - fresh rebuild 350 small block - TH350-NP203 - 4.1 end gears - IMPCO425 mixer - IMPCO model E vaporizer
project: 1977 GMC C15 Suburban - 454 big block - TH400 - gasoline
sold: 1986 Chevrolet Suburban K20 Silverado

BigBlockMopar
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Re: Building a fresh 360ci engine for mileage & power

Post by BigBlockMopar » Sat May 05, 2018 4:34 am

No pics yet of the installed engine. My hands were greasy for the last 4 days :)
Will take some pics today.

The oil filter is currently angled away from the headers and is already using a (factory) adaptor.
I reused it from the old engine, but now this exact thing is leaking on the large bolt holding it to the engine.
I don't think the angle-adaptor can be removed anymore now that it's captured by the header tubes, transmission bellhousing and frame rails (It's on the pass.side).
Hopefully I can manage to (reach and) remove the large 30mm head bolt and put a new gasket under it.
If it's like most of the other fasteners in this swap, it will probably also take some 2 hours of turning and flipping the wrench with every half flat of the bolt... :|
https://www.bigblockmopar.com
'73 Dodge Dart - 360ci - 11.3:1cr
MegaSquirt + HEI 7-pin timing control - Edelbrock AirGap - Cold Air Intake
IMPCO E / 425 mixer - A518 OD-trans - 3.55 gears - 225/50/17" tires.

BigBlockMopar
Posts: 346
Joined: Sun Sep 02, 2007 3:29 pm
Location: Netherlands
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Re: Building a fresh 360ci engine for mileage & power

Post by BigBlockMopar » Sun May 06, 2018 4:45 am

Fixed the leak, got the engine running and took it around the block for a short drive.
Still need to do a little more tuning and ignition wiring checked as the engine started giving 'sync-errors' with the MegaSquirt ECU when revved. Probably some grounding that needs to be improved.

Fresh and clean engine in an 'ugly' looking engine bay;

Image
https://www.bigblockmopar.com
'73 Dodge Dart - 360ci - 11.3:1cr
MegaSquirt + HEI 7-pin timing control - Edelbrock AirGap - Cold Air Intake
IMPCO E / 425 mixer - A518 OD-trans - 3.55 gears - 225/50/17" tires.

storm
Posts: 565
Joined: Wed Jan 10, 2007 10:10 pm
Location: NSW, Australia

Re: Building a fresh 360ci engine for mileage & power

Post by storm » Sun May 06, 2018 5:28 am

It is indeed a thing of beauty :wink:
Every job is a self-portrait of the person who did it. Autograph your work with excellence.

Fuel flow requirements calculations viewtopic.php?f=5&t=1638

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kikkegek
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Re: Building a fresh 360ci engine for mileage & power

Post by kikkegek » Mon May 07, 2018 2:06 am

cool. So how did you fix the oil leak? Im sure everybody wants to know ;-)

So will this engine gat propane vapor injection as its next upgrade?
daily: 1974 GMC 25HUNDRED Suburban - fresh rebuild 350 small block - TH350-NP203 - 4.1 end gears - IMPCO425 mixer - IMPCO model E vaporizer
project: 1977 GMC C15 Suburban - 454 big block - TH400 - gasoline
sold: 1986 Chevrolet Suburban K20 Silverado

BigBlockMopar
Posts: 346
Joined: Sun Sep 02, 2007 3:29 pm
Location: Netherlands
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Re: Building a fresh 360ci engine for mileage & power

Post by BigBlockMopar » Mon May 07, 2018 4:02 am

I was able to snake a long extention with a jointed 30mm socket in between the frame rails, torsion bar and a forest of headertubes to reach the large bolt holding the adapter in place.
After some fumbling and no chance to prevent letting oil drip all over the headertubes I was able to get the bolt out, put on a new reinforced washer and reinstall it again.

Had the car for a drive but there are some vacuum/valve issues to sort out at idling first I've found. I have a longer write-up on my site;
https://www.bigblockmopar.nl/2018/05/19 ... e-install/
https://www.bigblockmopar.com
'73 Dodge Dart - 360ci - 11.3:1cr
MegaSquirt + HEI 7-pin timing control - Edelbrock AirGap - Cold Air Intake
IMPCO E / 425 mixer - A518 OD-trans - 3.55 gears - 225/50/17" tires.

BigBlockMopar
Posts: 346
Joined: Sun Sep 02, 2007 3:29 pm
Location: Netherlands
Contact:

Re: Building a fresh 360ci engine for mileage & power

Post by BigBlockMopar » Thu May 10, 2018 6:10 pm

Anyway,
Been driving the engine for a number of days now and can report the increase in power is very noticable.
Also, I'm using the same timing setting and ignition advance curve as I used with the 318ci engine (max 32° adv. @ around 2800).

At first I created a 'safe' timing table with a 4 degrees retard across the entire map, so max. 28° adv @ 2800, but I found the engine a bit sluggish).
Carefully trying the 'max 32'-timing table, the engine woke up quite a bit more, while still no signs of any pinging, but I would need to install a knock-sensor to fully make sure about that).

I think the cold air intake and Edelbrock AirGap helps greatly in keeping the incoming charge nice and cool.
And perhaps the addition of the cylinder head groove in the quench-areas helped too, as maybe also the tight piston-to-head quench/squish clearance of around 0.030".
https://www.bigblockmopar.com
'73 Dodge Dart - 360ci - 11.3:1cr
MegaSquirt + HEI 7-pin timing control - Edelbrock AirGap - Cold Air Intake
IMPCO E / 425 mixer - A518 OD-trans - 3.55 gears - 225/50/17" tires.

BigBlockMopar
Posts: 346
Joined: Sun Sep 02, 2007 3:29 pm
Location: Netherlands
Contact:

Re: Building a fresh 360ci engine for mileage & power

Post by BigBlockMopar » Tue Sep 04, 2018 2:37 pm

Had the car on the chassis-dyno again last monday. DynoDay #4 already :shock:

The very first DynoDay with 318 'managed' a shamefull 145hp at the rearwheels.
During DynoDay #2 I managed to 'up' this to 170hp.
DynoDay #3 was evenmore shameful as a switch to headers, X-pipe and Borla mufflers managed no improvement at all at that time.

Now, at DynoDay #4, the installation of a higher compression 360ci engine made some welcome difference this time.
We managed the get 230hp at the rear wheels this time.

Played around with the timing and AFR a bit.
Noticed clearly on the AFR-curve, the 6mm fuel-line and/or the lockup is becoming a restriction as AFR leans out above 3800rpm.
https://www.bigblockmopar.com
'73 Dodge Dart - 360ci - 11.3:1cr
MegaSquirt + HEI 7-pin timing control - Edelbrock AirGap - Cold Air Intake
IMPCO E / 425 mixer - A518 OD-trans - 3.55 gears - 225/50/17" tires.

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