MG Sports Cars

Hi all!!

Long time no speak. Been busy with all sorts. Mainly work and saving for car parts.

After 12 long months of rebuilding and making some alterations to the suspension I took the B out for the Retro Cars Show at Santapod and got some baseline test runs done and to settle the fresh built engine in. After a year off line I needed to make sure all was well. The brakes needed bedding back in and I wanted to get some test runs in before going all over the car trackside to check all the nuts and bolts that I could.

We then took the car to a nostalgia race event the week after (Dragstalgia) at Santa Pod to see if we could squeeze a little more out of the stock 4.6 engine ??

I have increased the boost to 12psi and have added a 150 shot of nitrous. I have modified the rear suspension to lock it down a bit tighter as well.

We only had 4 one hour race slots for testing during the day and we suffered a few problems with stuff like carb linkage being out of kilter which gave me a sticking throttle. A nitrous line that I hadnt tightend blew off, the dipstick seal in my tranny gave up and needed a fix as I ended one test run with my left foot covered in hot tranny fluid + a few other niggles. Eventually we got to our last race slot for the day and managed to have a go at a new pb. I now have the blower set to deliver 12 psi at 4500 rpm and I had the 150 shot of nitrous set to come in gently with a 75 fixed hit off the line with the other 75 shot coming in over 0.7 of a second from the point that I go wide open throttle. I have the ign timing set at minus 14 degree's for the 12 pounds of boost with another 2 degree's taken out for the nitrous. So its on the safe side :)

The end result for our last run of the day was Good and Bad??

The good part was pulling a 10.29 on the 1/4 mile.
The bad part was running a 60 foot time of 1.58 instead of the low 1.4 I should have run.

The net result was great as far as I'm concerned as I made a new PB with a poor 60 foot time. I'm back out on 11th August to see if we can get the MGB off the line a bit faster. If track conditions are good and I can get back in the 1.4's in the 60 foot I may be able to go sub 10.2 on the next day out :)

Here's a slo mo vid of the PB run. The rear end mods have managed to keep at least one wheel down (just) so I know we are on track for a better time. hopefully by the end of this year.

Sorry the vid is slo mo. i get my friend to do these so we can observe the cars reactions on launch.

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Regards to all

Perry

I love watching your runs Perry. That front wheel barely made a quarter turn. Kudos to you, that MG has to be one of the fastest around, and it looks really good doing it.

Jim

Thanks Jim

We counted 70 feet with that front tyre in the air.

I can almost smell a flat 10 second pass now. :)

It may not be this year as I'm running out of decent track time due to holidays and work :(

And the slicks are down to about 2mm of tread left. And I hadnt budgeted for new tyres this season. So I'll have to try and make all passes count for the rest of this year.

Hopefully the 11th august will see us backing up a 10.2 pass so I can be confident that it wasnt a fluke.

regards
Perry

Update:
May be a bit long winded !!
The story has a sad beginning, a tense middle, and hopefully a happy ending.. :)


Well........ we went out in August and had an accident !!

The car is ok, but the engine did not come home in one piece :(

My fault entirely though. We had done several runs and could not get the rubber to grip. By 3pm I said to my Son that we should put her on the trailer and watch the rest of the racing. But the queue was very short with only about 15 mins waiting which meant plenty of time for at least 4-5 more passes.

So I decided to play with nitrous settings to see if we could ease her off the line on boost only and then bring in the nos for 2nd and 3rd gears. I also decided to remove the metering jet in the nitrous solenoid. The reason being that the solenoid should be rated to flow a 150 shot with no jet fitted. What I had not remembered was that when we rebuilt the motor I also modified the solenoids to flow a 250 shot. MISTAKE No1...

I then set the nitrous contoller to delay the nitrous for 2 seconds and then to bring it in at 50% with the other 50% coming in over 1.5 seconds. This timed programme should have operated as soon as I went full throttle off the line. I even tested the programme as I ran it through the programme check menu. But somehow during the time when i set the programme and thought that I had entered it I must have missed the menu scrolling or hit a wrong button. Because I actually selected a pre instaled flow test programme which basically hits the system full on for 10 seconds. I use this for flow testing the fuel side.

So I hit the pedal and she left the line so hard that (this time she hooked up for some reason?) that a few small itms on the console by the shifter went into full flight and flew past my left ear onto the back seat. Front wheels were off the ground and the car pulled pretty wildly to the centre line on the strip. I knew this wasnt normal so I did what every DIY racer would do in this situation. I smiled and kept my foot hard in :)

The shift to 2nd gear was so hard that the tranny had trouble making a crisp shift. By the time I hit 3rd gear as the shift light came on I was only about 700 feet out. She snuck into 3rd and pulled hard again for about a second before it went bang. The bang was a huge backfire followed by some heavy metal music :)
I was pulling just over 100mph so I backed off and hit the footbrake only to find the car starting to drift. I backed off the brake and went on again. Still slipping and sliding. In these few seconds my brain had already worked out that I was driving over my own engine oil. So I pulled tight to the track all and eased the brakes on again. It took me 400 feet to stop. As I came to a standstill I could already see my Son and the Rescue crew on their way down from the top end for me (my Sons works on the rescue team part time) in their truck and the quad bikes. As I sat there with my heart pounding and my breathing somewhat elevated I heard a strange noise. I took a couple of seconds for me to realise that the engine was still idling?? Although it sounded like a machine in Willy Wonka's factory :)
So I shut it down and got out. I could see a 400 foot trail of oil on the track behind me.

After the recovery I was back in the pits with large coffee and laughing with friends as they explained to me how the run looked from trackside. The poor clean up crew then had an hour on track to clear up my mess. One of the crew came to me after the clean up to deliver a bag full of metal. They normally wouldnt do this for a RWYB guy but as they know me they did.

We looked at the engine with a torch and could see through the headers that I had a large hole in both sides of the block adjacent to pistons 3 and 4.

The following weeks investigation showed that the con rod on 3 had snapped and the rod on 4 had bent. The flailing rod had punched holes in the side of the block, it had hit the lifter gallery in two places and jammed valves open, it had also managed to get up inside no3 bore and make a mess of the piston as well as breaking the liner. The back fire had lifted the blast door on the blower manifold and bent the retaining springs and also had cracked the inlet manifold in 3 places. The jammed valves had hit the pistons and bent. This was when I decided that this Ebay engine was finally toasted :) The flex plate had also failed.

I had already suffered 11m months off track while saving to have top hat liners fitted to this block only to trash the whole engine after only 3 months of racing due to a stupid mistake. You have no idea of how pissed i was with myself for making such a rookie error !

I was not going to be without a car for another season. So I started talking to race buddies, called in some favours, got some help and sponsorship from my boss and thanks to a very good friend who knows and old Rover V8 Challenge racer from back in the day I got to find my way into an Aladdins cave of Rover V8 racing stuff. Actually it was a large garage full of Rover stuff on a farm about 50 miles from home.
Long story short! I purchased and old race engine for not a lot of money.
It has now been freshened up and works just fine. Its a Rover 3.9 litre stiff block which has been bored and stroked to 4.8 litres. It has been X bolted and has super nice heads with big valves, heads are O ringed, solid custom ground nitrous / blower cam with full kenne Belle roller rocker set up, big custom made main journals, crower rods, chevy forged pistons, total seal rings, modified oil system etc etc... After having seen the engine apart i would say that pretty much all you can do to a Rover V8 has been done. So the story may have a happy ending in 2013.

I took the car for shakedowns a while back and after several runs and adjustments she made an 11.2 on the strip with only 6psi of boost and no nitrous. But AFR was way too rich.
On 1st December I put it on the rollers as it was for the 11.2 pass. She only made 361hp with AFR at max rpm of 9.8 ??
I found the dissy advance was not operating and this was running way too retarded. So I adjusted on the MSD remote to advance the timing by 6 degree's to bring it to where it should be at 7 degree's of retard for the 6-7psi of boost. She then ran 402hp on the dyno with AFR still running high 9's.

This is when I realised that the edelbrock 800 is too small for this new motor. The AFR is ok up to 3900 rpm. but as it hits 4000 the fuelling goes off the scale rich. I did try fitting smaller jets but it didnt make a difference really. My Ebay engines are normally built by re using my forged pistons with new rings and honing the bores at home. I normally run large ring gaps for heavy nitrous use which is why my engines tend to breath heavily. But the modified 3.9 does not really breathe heavy at all. I guess the build quality and total seal rings make it much more efficient than my Ebay smokers. So I did some sums based on the engine running at 90% VE and the sums came out showing that the carb needs to flow around 930cfm. Way above the range of my 800 cfm Edelbrock. Again I lucked out thanks to race buddies and their contacts. I have just taken delivery of a fully working Holley 1050 Dominator for the sum of £115 sterling !
The carb is now fully apart for ultrasonic cleaning. The downside is now waiting for Holley perfomance to send the adaptor plate (4150 to 4500 size carb) from the USA so I can bolt it to the blower. I paid for the plate on 12th December on their Ebay shop. And as of right now they still have not marked it as sent. positive feedback was sent as soon as i paid. Maybe they are slow due to the holiday season??

I wont bore you with any more stories about the latest problems. I will leave you with some pictures of the damage and the new engine if the forum will support the photo's.

Perry, the CARNAGE is top shelf. You did it well. Usually I just bust a piston or drop a valve. :) Keep up the good work.

LOVE the flex plate Perry! You right well *demolished* that engine, yeah? Sharp looking replacement though. Perhaps it is time to consider a 300 Buick block.

Jim

Quote:

So I hit the pedal and she left the line so hard that (this time she hooked up for some reason?) that a few small itms on the console by the shifter went into full flight and flew past my left ear onto the back seat. Front wheels were off the ground and the car pulled pretty wildly to the centre line on the strip. I knew this wasnt normal so I did what every DIY racer would do in this situation. I smiled and kept my foot hard in :)

Awesome! Did anyone get it on video?

Havent found any vids as yet Curtis :(

We didnt have camera's rolling as this was just test and tune really. And I hadnt asked the resident photographer to look out for the car as we were not expecting anything more than a test run ??

I do hope to have some vids and pics of the new engine being shaken down on the dyno when my cameraman gets back from holiday.

I'm just finishing the strip down and clean of the Dominator carb now. Tomorrow it will be in a solvent bath so i can blow through all the holes and make sure its clean before I put it back together with a few modifications ready for fitting as soon as the adpator plate arrives :)

Hopefully I'll have it running before I go back to work on 7th January.

Merry Christmas to all you folk out there.

Regards
Perry

Perry, Did you go to a PowerGlide tranny?

Hi Jim.

I'm still using my TH350 in the MGB. Its 7 years old now :)

Darn it!!
That new engine was ok until i hit it with boost. The Chevy pistons let go ??

They were supposed to be TRW Racing pistons and they were quite soft.

There was no major damage luckily. So I tore it all down and re built again. This time I dropped CR down to 7.5:1 and fitted Omega pistons. There has been a lot of work since my last post on this so I'll trim the story down. Last Sunday i took it out for some serious shakedown passes. I managed to beat my old PB of 10.29 with a 10.23 second pass. Its not a big improvement but its going in the right direction and its with 3psi less boost and a 100hp less nitrous.

A friends wife recorded it on her phone.. :)

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It wasn't a terribly hard launchso I see single digits in the not too distant future. That thing is quick!

Certainly a worthy run. Love it. Really puts it to those who don't think a Rover powered MGB can be quick.

Jim

AHA!!
I figured out how to download from my new camera. So here are some shaky vids from Fathers day :)

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I just have a few things to sort out before next saturday and then I should be able to launch hard for some real full on test runs. Assuming the drive train holds out I'm hoping that my 9 will be with me in July :)

Good 'ole Rover V8 !!!

Regards
Perry