MG Sports Cars

What a cool car!





Details: Ivan Collins' 1973 MGB GT with Ford 347cid "302" V8 Engine - including specifications and 59 photos

Ivan your car is really cool!! You have done a good job on it. I wish I had done something like this at the age of 27!!

Cheers
Byron

Great job Ivan! If you continue to have cooling problems, check out the fans from Volvo 970's and a few other models. It's a 2 speed fan that moves way more air than amy of the after market ones I could find. Mine hasn't even kicked into high speed since i installed it a swhile back. Another, maybe better fan is the Ford Taurus. It is a little thicker than the Volvo but looks like you have plenty of room. The Taurus fan is integrated with the shroud.



Edited 1 time(s). Last edit at 02/01/2013 10:59PM by rficalora.

To add to Rob's cooling comment above, you might also benefit from sealing off the front of the radiator fton the engine compartment behind. All air entering, and therefore pressurizing, the engine compartment needs to pass through the radiator core. Air flows from high pressure to low and will take tha path of least resistance if allowed to go around the radiator. If the pressure in the engine compartment equals the pressure in front of the radiator you get no airflow and the car gets hot. There is some good reading here

[forum.britishv8.org]

An original aconite gt turned into v8 car? Blasphemy! I guess there's two of us in the club now!




I like so many things about this car, but most of all I like how many details Ivan figured out himself and did just a bit different. It's kind of a fresh version. I'd like to do my own 3 link, no way I'll be able to pony up for the Fast Cars IFS though.

I've seen several cars lately that have me thinking about doing my gt dark red with a matte clear.

Ivan, I suggest measuring "underhood" air temp, when engine is running hot. This should help you make the decision for hood louvers/vents, and/or fender vents. Nice build, roverman.

Rather than measuring temps, I would measure differential pressures to see where the louvers/vents should go. You can get a Magnehelic gauge cheap on Ebay.

Your car looks great, congratulations! I'm likely going to go with the 8" Ford rear with a custom 3 link myself in the not-too-distant future. If anyone has any pitfalls or recommendations along those lines, I'd be all ears. I'm still breaking my car in with the stock rear and it's pretty obvious it's not fully up to the task.

Thanks for sharing.

Scott

Ivan, If you look in the MGB gallery, you'll see vented hoods that work well, for ejecting unwanted heat .Many production cars tend to have negative pressure on outside of hood, approximately 1/3 back from leading edge. This tends to be a good area, to extract hot air from fan wash and engine heat.True,as Jim suggest, a low cost Magnehelic, will help you locate target areas. I prefer the gauge that reads +/- pressures, like having 2 gauges in one. Cheers, roverman.

Wow, I'm really behind I have been so busy Feb through March I didn't even realize yall were helping me and giving me pointers. Thanks for all the comments.

It's been real nice here lately so I've put probably 150 miles on the car in the last week and a half. No cooling issues but I really like the idea of the pressure difference measuring and the temperature. You guys seem to really think the louvers are the way to go.

On a side note, does anyone have any idea why a serpentine belt would chirp all the time? I have to rub a little brake fluid on the belt every time I drive it to alleviate the chirp/squeal.

Ivan,
Great car you have there!
In regards to the chirping belt, I think you'll find it due to "misaligned drive pulleys". Have a look at this:
[www.gates.com]
Ken

Too bad they didn't give angular specifications in that article.

Jim

On my serpentine system "homemade mostly" the idler pulley screamed badly, I used a washer that I chucked in the lathe with a small amount of runout and faced it off creating a wedged shim, noted the skinny side and clocked it to compensate the bracket fault, worked like a champ.

Well I took a closer look at it last night and with the belt off its perfect alignment, the problem is with the tension on, and the way I have oriented the idler, its pulling it outwards and creating a bad misalignment. Weird thing is the misalignment is coming from within the tensioner and not any flexing of brackets. Basically I set it up to tension up to the 3:30 -4:00 position but it looks like this thing was designed to be tensioned to the 6:00 position. (tension on mine is counter clockwise) So I need to redesign my bracket.

To Jim's point, I would like to know what the limits are as well. Seems like that would be a key point in an article like that.

I would have run a v-belt but I needed to use the explorer timing cover (for clearance) which uses a reverse direction water pump so that killed my V-belt dreams. However a properly setup serpentine system should be more efficient, so I just gotta get my crap right.

Ivan a photo would be a big help. If you can configure it so that the tensioning load (spring?) is applied equally to the front and back of the tensioner pulley that should correct the misalignment. A fundamental point but one easily overlooked. If applied by the axle it is best for the pivot shaft to be in line with the pulley centerline if possible as well.

Jim

It's a pretty bad picture but I've already started machining a new bracket to move the pivot point on the tensioner to where the blue circle is. Basically rotating it up ~80 degrees (its not level currently even though it looks that way in the picture). The red is where the belt currently goes and should pretty much stay the same after the new bracket is in.

Looks to me at first glance like maybe you have a bit too much belt and are relying on the tensioner to take up the slack. With 180 degrees of wrap, alignment is probably a lot more critical.

Jim

I fixed the belt problem. I attached the picture of the new setup.