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V-8 Engine Tech

Rebuild gets underway at last.....

Mopar Big Block Talk

by Grant » Tue Jul 30, 2019 10:15 am

Rohan Christmas wrote:The motor is just running in. They haven't been doing full power runs.

I understand that Rohan, but my point was that at 2100revs Erics engine was only making 38hp and 94 Ft/lb as opposed to 450ft/lb and 217hp at 2500 with the other newly rebuilt engine I posted up.
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by Roh » Tue Jul 30, 2019 10:39 am

Grant wrote:
Rohan Christmas wrote:The motor is just running in. They haven't been doing full power runs.

I understand that Rohan, but my point was that at 2100revs Erics engine was only making 38hp and 94 Ft/lb as opposed to 450ft/lb and 217hp at 2500 with the other newly rebuilt engine I posted up.


In that video the engine was only under light load. The carburettor blades would hardly have been open. Once the engine has been fully run in and after the oil has been changed a full power run can be done with full throttle.
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by Chris_R » Tue Jul 30, 2019 11:02 am

Oil pressure seems excessively high.
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by Roh » Tue Jul 30, 2019 11:23 am

Chris_R wrote:Oil pressure seems excessively high.


It's still warming up though.
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by Jorrocks » Tue Jul 30, 2019 8:28 pm

Guys,
I don't have an answer to the epic torque & power figures, but as Rohan pointed out it had just been started so under no load at all. The oil pressure was that high because we hadn't adjusted it (it's an externally adjustable unit), and were also trying to get the recalcitrant lifter to co-operate.
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by Jorrocks » Fri Aug 02, 2019 7:07 pm

Well, the lifter was persuaded to work properly after an hour of alternately applying oil and high pressure air (The piston/plunger had a tight spot at the bottom of its travel that was causing it to jam) so the engine was dyno tested properly yesterday. I couldn't be there to see it in person unfortunately, but I'm told the torque peaked at 3300rpm, and was tailing off slightly by 3700rpm where it was reading 571ftlbs! I'll get the full printout when I collect the engine next week.

The oil pressure is now set at 80psi hot.
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by Chris_R » Fri Aug 02, 2019 9:31 pm

Jorrocks wrote:The oil pressure is now set at 80psi hot.

Oil pressure seems excessively high. I would have thought around 50psi would be more appropriate.
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by Jorrocks » Sun Aug 11, 2019 9:53 am

The dyno printout:

5BC728D4-BAFE-4577-8EC2-C33B7381191E.jpeg
5BC728D4-BAFE-4577-8EC2-C33B7381191E.jpeg (141.37 KiB) Viewed 442 times


As you can see, the graph is only reading from a point where the torque has already peaked (Max torque was between 3000-3300). This is because the dyno couldn’t hold steady to get a reading as it was unable to move enough water due to the low engine revs (I hope I understood that correctly, but I think the volume of water being pulled through the dyno is governed by the revs of the engine)

7ACFD6C7-ACB0-44AC-A87C-560F82A5A04E.jpeg
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by Jorrocks » Sun Aug 11, 2019 10:03 am

Grant wrote:may I ask who's doing the work? ..


The engine was built by Rob Loaring and Nick Davies at ICE Automotive

http://iceautomotive.co.uk/
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by cannonball » Mon Aug 12, 2019 11:00 am

Good engine people, I know rob has always done a lot of r&d with cylinder heads, I would prefer 80psi than 50
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by Roh » Fri Aug 16, 2019 9:13 am

What inlet manifold and carburettor did you use?
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by Jorrocks » Sun Aug 25, 2019 11:10 am

The manifold’s an Edelbrock Performer dual plane (Not the RPM, as apparently it causes bonnet clearance issues).
The carb on the dyno was I think a 650cfm, but I will be using FiTech EFI which equates to 850cfm.
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by Julian » Sat Aug 31, 2019 1:12 am

RPM fits but you need a drop type air cleaner.
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by Jorrocks » Sat Aug 31, 2019 3:28 pm

That's useful to know Julian, I may look at changing to either an RPM or an Indy dual plane, although with efi a Torker single plane might be interesting.
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