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Shouldn't have done that...

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Took the TR8 to the dyno. Now I'm depressed.

Let's just say that it has lower hp numbers than my TR6 and leave it at that...
 
That is depressing Alan, I thought that one was supposed to have mildly built engine. Hows the tune on it? Did you run the dyno with the sniffer to see how your A/F ratio was? Stock, the carbed TR8s did only make 137hp at 5000 rpm but 174 lbft at 3200. With 8.1:1 CR.
 
Does anybody drive their car by the dyno? Does having 150 HP on a piece of paper versus 130 HP make it more fun?

Dyno's are a tool for tuning. In many cases they have become an ego deflating tool. But the car is what you drive and have fun with, not the dyno.

I'll dyno mine again after break in to make sure that the ignition carbs are tuned properly in a road situation and after that who cares what the numbers are?
 
It's supposed to be a built 4.0, but it looks like it was built out of bean cans...

Mustang dyno.
I got 89.6hp @4490rpm /99.4mph and 157.3ft/lbs @2813rpm /62.3mph
Numbers are corrected.

The sniffer was a handheld - these guy's dyno was set up to hook in through OBDII - and I stopped looking at it when the car started gushing water. I thought it had popped a hose initially, but it was coming out of the expansion tank.

The engine is clearly not well.

Just for comparison, my TR6 puts out 125hp on a Mustang dyno, and is quite fun to drive at that power.
 
Brosky said:
Does anybody drive their car by the dyno? Does having 150 HP on a piece of paper versus 130 HP make it more fun?

Dyno's are a tool for tuning. In many cases they have become an ego deflating tool. But the car is what you drive and have fun with, not the dyno.

I'll dyno mine again after break in to make sure that the ignition carbs are tuned properly in a road situation and after that who cares what the numbers are?
Click to expand...

You might care if you expect 110hp and find it has only 50. You'll be thinking something is wrong with your engine build...
 
My MK III GT6 was supposed to have 98 HP. I had taken the head off and ported and polished and then had the head milled and then did a valve enlargement. Changed the carb filters to open filters and revamped the timing. Added a big bore exhaust with only a can muffler. Ran good. Then I took it to the dealer to buy some parts ( yeah dealers were still in business at that time) and the TR6/GT6 mechanic came out to look at it and asked if he could drive it. After the drive he ran it on their dyno they were so astonished, they had to do it twice as it popped 125HP.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]You might care if you expect 110hp and find it has only 50. You'll be thinking something is wrong with your engine build...[/QUOTE]

Alan,

I agree with a as radical a difference as that. But I'm not going to fret if I'm not at 150. I just want it to run properly and last until I'm too old and feeble to care. :lol:

Which won't have to be too long at the rate I'm going....
 
Then you see why I'm not happy. I was expecting 180hp at the rear wheels based on the work that was supposed to have been done to the vehicle.

To find that it has less than 1/2 of that was a rather unpleasant surprise. The fact that I recently dyno'd the TR6 and it has more hp than the v8 just rubbed salt in the wounds...
 
OUCH....That would bug me too after all that.

Even more so, I don't like the fact that water was coming from the expansion tank. Have you run a compression test yet?
 
No - I'll do it tomorrow.
I just drove it home and put it in the garage.
It isn't smoking and the oil looked fine, so I didn't bother before now :frown:
 
Oh wow Alana - sorry to hear it.

I'm expecting to find the same when I get around to bringing the TR8 to the dyno, which is why I am dragging my feet.

Are you sure the intake/fuel deliver is correct/healthy?
 
No, I'm not sure at all. It's as it was sold (plus a thousand or so miles driven).

I'll do a compression test when I get back this afternoon. jooi: Anyone know what's normal for these engines?

It's going up to visit Woody on Thursday. Hopefully he'll be able to figure out the problem without the need for major surgery to my wallet.
 
Maybe the rings haven't fully seated yet. My TR8 has a recently rebuilt engine but was way down on power. Following the advise from some of the guys here I did a couple of oil changes, and drove the snot out of it, and she is definitely getting stronger.

One can hope , right?
 
It's done 8000 miles since the rebuild so it ought to be run in!

Compression is good - 160 across the board apart from #2 which is at 155.

The problem was easy to see when I pulled a plug - they are bright white, so it's way too lean. Also #7 has a little oil on the outside, so the valley probably has a slight leak.

Now if I had the first idea how to richen it up I'd do so. Where's google when you need it...
 
I was told it has a Holley 500 on it. It says Holley on it, so there's a fair chance that that's correct.

I hate carbs. Never did get the idea about tuning them. They are all too much like "sacrifice a goat at the dark of the moon to ensure your idle circuit is aligned" rather than "test that the output from A is between 5 and 5.5"...

Stuff like this makes me even more determined to put something more along these lines on it eventually: top end help

Of course the guy at the dyno shop told me to stop messing around and put an LS1 with a T56 in it :wink:
 
Alan,

Did the guy with the sniffer get any actual readings? Was if rich or lean? Holley's can be jetted and tuned easily, depending on the model and Woody can set that thing straight for you. Nobody better than him in NE for Wedges.
 
It was reading 19 and change at idle. I initially thought his sensor wasn't calibrated right and just mentally blew it off. I didn't even think it would run that lean!

It does explain why it got so hot if it was like that the whole way through...
 
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