4.6 GT V8 Modified for road & track

[v8bloke]

Hello All

Just stumbled across this forum and thought id say hello.

I live in Wiltshire, England & Over the last 15 years or so I have been improving my factory V8 for track days.
Weight is down to 970kg and making 293bhp (more to come this year).
Here is a clip of the car at a track day. Rules are, no overtaking on corners and only overtake on the right side.

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http://www.youtube.com/watch?v=lWa4n7iVCm8

Ill post some pics when I have more time.

Thanks for looking
Mark

[BlownMGB-V8]

Great clip! Your car has a delightfully viscous undertone, I'm sure it is an absolute joy to drive. Just guessing you could make good use of a bit more grip at the rear. (Couldn't we all?) There's just something magical about 300 horses in an MGB, and your video does about the best job of capturing it of any I've seen.

Jim

[v8bloke]

 -- moved topic --

[castlesid]

Hi Mark,

Welcome to the even darker side. you'll find a few of us Brits lurking in here me, Perry also from the V8 Forum and a few more who possibly didn't realise it's a US site because of the name.

I'd seen the clip before but untiI I put it on full screen hadn't seen how much you were sliding the car around, strangely in the clips that appear at the bottom of the screen there was a certain Mr Blackwood going rather fast round a car park and what a lovely noise that blown 215 made Jim. look forward to when you get that 340 engine fired up..

regards.

Kevin.

[v8bloke]

Thanks guys.

Car does tend to oversteer when driven hard.
I have a 1inch front sway bar and a 5/8 rear sway bar (my own) and have tried various other setups.
If I increase the rear stiffness it oversteers even more. But when I reduce the rear stiffness it understeers less but is no where near as stable at speed over 120mph (read dangerous). I never experience understeer and am very happy with how the front turns in. Car weighs 970kg 52% front 48% rear so weight distribution pretty good. Perhaps this is as good as it gets with live axle.
Although it is slightly tail happy the car is very forgiving and it is quite rare to spin me out (unless its wet).

Finding this site really interesting.

Kevin
We must put faces to names sometime.

Mark

[castlesid]

Mark,

Yes that would be good, I haven't been out and about with my MG due to health issues last year but hoping to get out there a bit more in 2010

Do you ever do a track day at Brands as that is just down the road from me?

Yes a very good forum with a load of great guys, have you found the engine & transmission section, if not run your cursor up to the web forum and click on web forum hub and scroll down, for some odd reason this not accessable from the drop down menu.

Kevin.

[BlownMGB-V8]

It should be there Kevin, labeled, "Drivetrain Issues"?

Mark I was referring to your wheelspin exiting the corners, the handling of your car looked spot on, to me at least. But oh my, all that power! (Don't cha just love it?)

Kevin, it's odd but I couldn't find the one you referred to. Do you have a link by chance?

Jim

[mindseye]

very nice clip....sounds really good, like a race car should, because of the exhaust I have in mine it sounds more like a muscle car but that is ok too.....I am curious as to what kmph you have topped it out at?....300 hp in an mgb has got to be ridiculously fast

[v8bloke]

Jim
Problem is wheelspin = tyres dont last long.

John top speed in that clip according to speedo 140mph but sat nav says 132mph
Would be interesting to see what it would top out at with a long enough straight.

Car in bits at the moment.
Fitting new Merlin cylinder heads.
Grafting on Golf (rabbit) Mk1 wheelarches to the front.
Custom re wire.
New complete exhaust system 2.5 inches from 2.25

Thanks
Mark

[MGBV8]

What size tires?

[v8bloke]

Carl
Front 205/50/15
Rear 235/50/15

[castlesid]

Jim,

Strangely I can't find it now but obviously someone has put it on you tube, it was in the links that yiou can bring up at the bottom of the screen, there were a load of BV8's

Kevin.

[rficalora]

RE:  Rear 235/50/15

I was able to find 225 & 245/50/15, but not 235/50/15... what brand/model tire are you running?

[Mr. T]

Welcome Mark - I've seen your vid a couple of times prior to your post - I can't seem to get enough of mg's with v8's!

[v8bloke]

Rob
Using Toyo R888 235/50/15

Tony
I know what you mean, they seem to be somewhat addictive. In fact 2 of my friends are building copies of my car after some passenger rides got them hooked.
Build cost is in the region of £10k.

Mark

[johnny wells]

Mark,

Pictures, please.  Lots!

Regards,

Johnny

[MGB-FV8]

Hi Mark and WOW!  I've watched the video three times; it got me a little daisy.  What kind of speed did you get your car to on straight away (MPH)?

[v8bloke]

Johnny
Pics as requested.

Jacques
Max speed on that particular track is just over 130mph measured on sat nav. Speedo goes off the scale (140mph+)
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[crashbash]

What's been done to the engine to get you hp? If i may ask.

[v8bloke]

4.6 top hat linered crossbolted block, Huffaker inlet manifold/edelbrock 500 (1404). Self ported heads with stage 3 valves & 27.2cc chambers. 4.0L pistons making the compression ratio 11.04:1. Mechanical 238 cam. RV8 style single straight through silencered exhaust. Mallory magnetic dizzy.
Think thats about it.

In the process of fitting Merlin heads which have larger valves so hoping to break the 300 barrier. (currently 293bhp).

Cheers
Mark

[johnny wells]

Mark,

Interesting tire set up; 205 - 235.  What wheels (Minilite?) and what width and off-set you runn'n front and rear?

Stock MG axle with 3.07 ratio?  Quaife limited slip?  Stock leaf springs or someth'n different?  Any brake mods?

Thanks for suffering the questions.  Love the grille . . . and the stance at speed.  Too much fun!

Johnny

[v8bloke]

Johnny
Wheels are made by Compomotive ML  with special offsets. 15x7 fronts(ET5) and 15x8 rear (ET3)

Axle is stock MGB with 3.07 and quaife LSD

Springs are the best handling upgrade ever. Composite from Doug Jackson.

Brakes are Wilwood superlite with 298mm vented discs up front and Ford Cosworth 4x4 calipers with vented wilwood discs at the back.
Also made a Bias pedal box with dash adjuster.

[MGBV8]

"Springs are the best handling upgrade ever. Composite from Doug Jackson. "

Really. I've heard of problems with those delaminating  when used in high horsepower MGs.

[v8bloke]

""Springs are the best handling upgrade ever. Composite from Doug Jackson. "

Really. I've heard of problems with those delaminating when used in high horsepower MGs."

Well Ive been using them since 2001 and have been very impressed.
I think its important to have some form of axle location and anti tramp bars that fit properly without binding as the suspension moves.
In fact I have bought a second set for spare.

I have seen a set shear at the thickest part just in front of the axle and think it was due to Anti tramp bars that didnt follow the same arc as the axle movement.

Has anyone got more information on the delaminating?

Mark

[Mr. T]

Johnny,

If that's your car in the avatar, you've got an interesting hood scoop - appears to be an rv8/ford hybrid?

Maybe you could start another thread with a few pics.

Thanks, Tony

p.s. apologize for the quick migration off topic.