Dave Russell's engine

[Lin]

Dave,
After all your recent "improvements" do you have your engine back in the car yet? Did you put it on a dyno? If so, what kind of numbers did you get? Satisfied with your changes?

Lin Rose
1960 BT7 in restoration
1959 Bugeye

 

[Dave Russell]

Hi Lin,
I had it back in the car & running well about the first of April. I have only put it on a borrowed G-Tech dashboard dyno. At the rear wheels it shows about 155 lb/ft torque at 4,000 rpm & 137 HP at 5,500 rpm. Not sure what the engine HP would be, maybe 10% more?

There was negligible power loss at lower rpm but a great increase at higher rpm. It will slightly pull a good XKE on a 5 mile uphill run at 110 mph plus. 3.54 axle ratio at 5,500 rpm. On a flat, it will pull 5,500 rpm in overdrive. I guess I'm satisfied. It was a rather large expenditure, but it now performs like I think it should have originally, & I know it isn't going to self destruct.
D

 

[Lin]

Sounds sweet, Dave! I wouldn't want to meet you in a dark alley.

Lin
1960 BT7 in restoration
1959 Bugeye

 

[BobHorvath]

Dave Is there a list of mods you have installed?

 

[GregW]

Hi Dave,
I’m curious if you think the DW crank was worth it. I looks like your peaks are designed lower than what the crank could handle. I had considered their crank, but when I added up the connecting rods, flywheel, etc.(since they only seem to work in a kit) it was way more than I wanted to spend.

 

[John Loftus]

Hey Lin,

Where were you back in March?

Thread about Dave's motor with pictures!

 

[Keoke]

Hey Lin,

Where were you back in March?

Thread about Dave's motor with pictures!

\


He was trying to get that ugly nut off !!---Keoke-- /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif

 

[John Loftus]

He was trying to get that ugly nut off !!---Keoke-- /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif

/bcforum/images/%%GRAEMLIN_URL%%/grin.gif Actually, I see that Lin jumped on to that thread near the end so he was here. Still, it was a good excuse to show the pictures of Dave's most excellent motor. So, how's the 6 cylinder motor coming along that you sent up to him?!? Have you mortgaged the house or come out of retirement to get the DW parts yet??

 

[Dave Russell]

Hi Dave,
I’m curious if you think the DW crank was worth it. It looks like your peaks are designed lower than what the crank could handle. I had considered their crank, but when I added up the connecting rods, flywheel, etc.(since they only seem to work in a kit) it was way more than I wanted to spend.

Hi Greg,
DWR has a history of building fast durable engines, I trust their parts & quality. First, remember this is a very long stroke engine (4.375") & doesn't take kindly to higher rpm without a lot of help. It also explains why a 12 pound flywheel is not objectionable. The new crank, rods, & pistons were prompted by several things:

1- The stock crank frequently breaks at rpm over 5,000. I wanted to be able to turn it to at least 6,000 with a safety margin. The crank, ATI balancer. etc are good insurance.

2- The split pin clamping & design of the rods was questionable. On the stock engine, the rod big ends & crank journals are actually offset from the bore center lines. The new crank & rods are lined up with the bores. This is the reason that the non offset crank & rods must be used together. Each rod & piston weighs 1.25 POUNDS less than original which greatly reduces high rpm stresses. Having crank, rods, & bores on the same center lines also helps.

3- Since the crank was designed for eight bolt flywheel attachment, it made sense to go with a light steel eight bolt flywheel. I never was comfortable with the original 40 pound flywheel & four bolt attachment.

4- As aircraft owners know, metals that are cyclically stressed such as crank & rods, are subject to fatigue fracture & are replaced on a periodic basis even if they don't show signs of failure yet. I thought that at 90,000 miles & 50 years, the original parts had possibly reached the end of their "safe" life. It didn't seem reasonable to push these old parts to way over their original design limits. Stresses are expotentially increased as rpm goes up.

Yes, it was expensive, but you only get one chance to do it right. I know from experience long ago that exploding engines are also expensive & a lot of trouble. Worth it to me, maybe not to others. The down side is that none of this "good" stuff shows on the outside. But I know it's in there.
D

 

[Lin]

Hi John,
Yes, I was on the original thread, but frankly I had forgotten if Dave had really given us a report on how the engine was doing since reinstallation. I also saved all those images of the gorgeous components that had me green with envy. I have the Denis Welch alloy head/valve assembly, but had to stop there. Hopefully, optimistically, and perhaps foolishly I am thinking that I may have my engine back in 10 days or so. It is starting to get exciting now. If I could just shave off that ugly nut I would be set!

Lin
1960 BT7 in restoration
1959 Bugeye

 

[Dave Russell]

Dave Is there a list of mods you have installed?

Hi Bob,
The list is very long. It would take a short book to detail everything.The best way to say it is that the block itself is the only original part.
D

 

[GregW]

Thank you Dave. I appreciate the detail you always go into. Understanding the “Why” can be more helpful than just the “What”.