Blue Racing Stripes

[jjbunn]

I have some blue racing stripes that I bought a while back to apply to Harold. These are twin 6" stripes in navy blue.

About a year ago I remember seeing a photo of a white GT with blue stripes, which I thought looked fabulous, and was the main reason I ordered them. Now I am trying to remember where I saw this photo: I had the impression it was a forum member here's photo, but I can't find it. Google images, and the Registry at MGExperience.net have also drawn a blank. I should have bookmarked it!

Does anyone remember seeing a photo of a white GT with blue racing stripes? Could you please point me to it, if so?

 

[100DashSix]

I have a photo of a white Austin Healey with one blue racing stripe.. Not that close, I know!

 

[jjbunn]

Well, I found one, but it wasn't the one I remember. This is Stephen Young's car (from the Washington DC MG club web pages)

What do you think of the looks?

 

[Steve_S]

I hope you have the performance to back up the looks! You'll get a lot of ricers wanting to see what you can do! /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

 

[PATR8]

I like the clean look of the blue stripes on a white car, good choice

 

[jjbunn]

I hope you have the performance to back up the looks! You'll get a lot of ricers wanting to see what you can do! /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

I think I have 0-60 in a minute or so, with a following wind, downhill.

Actually I am quite impressed with how nippy the GT is. I'm a little worried about over-revving, as the engine seems so lively. Just how high RPMs can one go in these cars, without risking blowing a gasket or worse?

 

[jjbunn]

I like the clean look of the blue stripes on a white car, good choice

Yes, that's my feeling, too. The stripes I've got are transfers, and easily removed, so I may just rub them on and see how I feel about them for a while.

 

[Steve_S]

It depends on how the engine is built. Chances are, you will reach peak power before you run out of revs. To give a more literal answer, you can take a standard engine up to around red line without blowing it up. I typically shift around 5200 RPM with a stock set up.

 

[jjbunn]

The engine is a 3 main bearing: does that make a difference to how hard it can be revved?

 

[Steve_S]

Really? In a 1973 car? That's very odd! Well, that explains why it feels like you will rev right off the scale. 3-main engines were only used from '62-'64, but they are popular with the racing crowd due to their lower friction than 5-main engines. The down side is less durability and they leak a lot of oil.

Being 3-main bearings won't make a bit of difference how high it can rev, but it will get there higher. It is more important however to make sure a 3-main engine is balanced properly because it is more susceptible to vibration and wear.

 

[Scott_Hower]

The engine is a 3 main bearing: does that make a difference to how hard it can be revved?

Probably not in how hard, but in how how willing. As a rule of thumb, 3 mains rev "easier" than a 5 main. Less friction from the other 2 mains. Although there were claims of crank whip/bearing wear, which is why I suppose, the engine gained two more mains.

The first problem you're likely to encounter is valve bounce/float. The springs just can't keep up.

As Steve said, with a stock cam, you'll run out of the effective power band before you hit redline, so it's all noise at that point. Might as well grab another gear and repeat.

 

[Bret]

I’d be very interested in knowing how a 3-main got in a 73?

The first problem you're likely to encounter is valve bounce/float. The springs just can't keep up.

As Steve said, with a stock cam, you'll run out of the effective power band before you hit redline, so it's all noise at that point. Might as well grab another gear and repeat.

Valve floating & bouncing is probably the biggest limit to our stock 1800cc engines. That’s the main reason why when my O/D tranny swap & EFI kit installation is completed, I’m going to focus on improving the valve train of my 78B.

Looking to improve how fast my B revs. While I haven’t decided if I’m going to use my 1.50:1 roller rockers – I’m definitely going to replace the old camshaft & go with “solid” rocker spacers to compensate for rocker drift, as well as some uprated (stiffer) springs and perhaps some uprated (lightened) lifters. Other than that – I’m going to lighten some of the spinning components like the pulleys and flywheel. Between those modifications and the quick throttle response of the EFI kit my 5-mains engine should rev much faster.

But again like Steve said without some internal upgrades – above 5000-5500rpms you’ve already passed your peak ponies in a stock engine.

 

[David_DuBois]

The biggest limitation on the upper rev limit of the 3main bearing engine is the split little end of the rods and the use of a wrist pin pinch bolt. Very high rpm and the use of compression braking can cause the bolts to fracture, resuting in disastrous results (I have first hand knowledge of what happens when one of these bolts brake in a TD engine). That said, as long as the red line limits are observed as absolute, there is no problem withhthe revs. Two things not to do with a three main bearing engine: 1) don't down shift to slow down, particularly at high speed as this puts excessive strain n the pinch bolts and 2) don't lug the engine as this will cause crankshaft flexing between the main bearings and lead to premature crankshaft failure. Cheers - Dave

 

[Steve_S]

Bret, why are you spending all that time and money to get more RPMs when your power band is in the mid range? Are you planning to build a high output engine?

 

[Bret]

Hey Steve,

Well, I was at one time. But the overall objective changed slightly with the addition of my Shark. Because with the 928 I don't need two warp speed rides. /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif

But because I’d already dropped most of the money on the parts & have them sitting on the shelfs. So I may as well go ahead & at least use some of them.

So right now going back to the "basic" original intent, I still expect to have the fastest “Kalifornia” emissions legal 1800cc Rubber Bumper B on the map.
/bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif

 

[Steve_S]

Oh, I didn't realize you already bought the parts. What do you have in there that allows such a claim? Inquiring minds want to know! /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

 

[Bret]

Oh, I didn't realize you already bought the parts. What do you have in there that allows such a claim? Inquiring minds want to know! /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

Well, one of the original goals was to use technology (EFI) & uprated components increase the engine's breathing and still burn efficiently & cleanly to remain within the emissions envelope.

However with the discovery that I've got a shaved/decked head & flat top pistons a lot of the work is already done for me. Only unknown is exactly what the compression ratio is or if the engine’s been bored-out or any other internal modifications. But our best guess is 9.0:1 for the compression ratio and the rest we’re just going to figure is stock for now. All of that & I still managed to pass our state’s strict biannual smog test without any problems.

That said I think we're highjacking this thread. So I’ll refer you to my other thread about the Tranny & EFI upgrade for more information about what I’m doing.

 

[Steve_S]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I think we're highjacking this thread[/QUOTE]
That never happens here! /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

 

[jjbunn]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I think we're highjacking this thread

That never happens here! /bcforum/images/%%GRAEMLIN_URL%%/wink.gif [/QUOTE]

No problem guys: very interesting discussion.

Harold now has blue stripes: pictures later

The engine is not the original. The Certificate of Authenticity states that the engine number was:

18V-672-L/14074

whereas the number on plate affixed to engine: 18 G-U-H 25079
which as far as I can tell from my reference material is a 3 main.

 

[jjbunn]

Stripes: