Dyno result from today with the MGB

perrymgbv8 · October 17, 2013, 05:09:47 PM

I have to admit that i wimped out today on the dyno. I ran the ign system heavily retarded by 7 degree's below what I should (on paper) be running with the modified Rover 3.9 engine.

But after the last years engine damage and rebuild cost i wanted to be safe. I could tell I was still way too retarded because I had blue flames coming out of the 12 foot extension pipes on the dyno.n And the run had to be cut a little short. As the rear wheels hit 147mph the slicks ballooned and one of them clipped the wheel arch metal and started to smoke.

I'm more than happy with the result. my modified Rover 3.9 litre engine is at last in the 500's

http://www.youtube.com/watch?v=o9hFNNKX2HA&feature=c4-overview&list=UUqIlXfSAoiZ--GyG4tfRrjw

Moderator · October 17, 2013, 05:24:06 PM

Awesome!

Just Awesome!

When you have a minute, please cross-post your dyno results here: http://forum.britishv8.org/read.php?10,26772

BlownMGB-V8 · October 18, 2013, 09:15:36 AM

Very impressive. That's a lot of power out of a Rover.

Jim

MGBV8 · October 18, 2013, 09:43:12 AM

From a 3.9?! WOW!

roverman · October 18, 2013, 11:58:37 AM

Congratulations Perry ! How about a build sheet/How it was done ? I suspect you used a lot of non-stock components, to reliably sustain all that power ? Cheers, roverman.

Moderator · October 18, 2013, 12:12:12 PM

There is a <a href="http://www.britishv8.org/MG/PerryStephenson.htm">How It Was Done</a> - although to find it in the gallery section you'd need to look in the factory MGB GT V8 section. Perry just promised me an updated version and new photos, so I'll be updating it soon!

DiDueColpi · October 18, 2013, 01:34:39 PM

Yes, impressive indeed!
I saw the before pictures on that other inferior forum.
That those rods didn't fail sooner is amazing.
That "s" curve is just the rod reacting to a compressive load that is exceeding it's limits.
It tends to get pulled straight on the toss (exhaust) stroke and fractures very quickly.
We see it often in the boosted Volvo white engines.
It first shows up as a very light knock at idle. Sounds just like a forged piston knock when it's cold.
Generally just after a detonation episode.
The very next pass tends to ventilate the block thoroughly.
Well done on the power numbers!
Cheers
Fred

perrymgbv8 · October 18, 2013, 03:51:22 PM

"" I suspect you used a lot of non-stock components, to reliably sustain all that power ? Cheers, roverman.""

The only non stock internals are +20 Omega Forged pistons and Chevy 5700 rods on the moving assembly. I have fitted custom billet cranks bearing covers as well with cross bolts added as the block didnt have them.

I'm very happy with the results. But bear in mind that I did say "Modified Rover 3.9"

When I get some time I'll send Curtis a full build report with pictures. I'm very pleased with the engine so far

Regards
Perry

mgb260 · October 18, 2013, 06:02:51 PM

Perry, Stock sleeves or tophat?

classic conversions · October 19, 2013, 03:49:01 PM

I wonder what a Mustang dyno would read.

perrymgbv8 · October 19, 2013, 05:13:03 PM

"Perry, Stock sleeves or tophat?"

Stock Sleeves Jim.

BMC · October 19, 2013, 11:42:12 PM

Awesome Results Perry!!!

Would love to see the how-it-was-done article on that engine and driveline. Always love comparative notes from one engine build to another.

Also, like Curtis said, post those results over on that thread. It's nice to have one place for results.

-BMC.

perrymgbv8 · October 20, 2013, 04:15:11 PM

Hi Brian
I'm putting together some pictures of the engine. Just need to figure out how to rescue them from my crashed laptop ? Shouldnt be too long as a friend is going to look at it for me

Regards
Perry

v8bloke · October 21, 2013, 12:37:35 PM

Awesome result you will be faster than ever!

Mark

cgill · October 24, 2013, 12:36:26 AM

Perry, congrats on getting the front page of MG Enthusiast magazine this month. Great article too!

Cheers,
Chris

perrymgbv8 · November 01, 2013, 06:24:23 PM

Thanks Chris.

It was a good day out to be honest. Simon Goldsworthy was very patient and followed me around all day to get the info for the article while I was prepping and racing the MG. He is a very nice guy.

cgill · November 04, 2013, 01:43:03 PM

He is a great guy and was also very patient with my story.

Migge · November 06, 2013, 05:15:11 AM

Talked to RUSSELL McCARTHY at the 6hours race event in SPA/Belgium this fall.

He won his divison and he stated that his MGB with 3.9 had 424 HP on the Dyno a few weeks before!!

The car ran fantastic with unbelievable power.

http://mccarthymotorsport.webs.com/