Kiwi scratchbuilt

[Russ Noble]

Actually Ross, taking a closer look at things, I think the problem may be not the depth of thread in the block which seems about right for the 154-4203s. Depth of hole 1 9/16", threaded length of stud 1 7/16". They snug down on the unthreaded stud shoulder not on the bottom of the hole, so I think if you machine the ends of the studs down as Dart suggest you will not do anything except reduce the number of engaged threads.

It would appear the length difference that I am experiencing is probably due to a thicker boss on the outer (exhaust) side of the Brodix heads and this is why I had to space the outer studs up. Not withstanding that the Brodix blurb specifys the 154-4203 studs. Can't measure the boss heights right now because my heads are still at the machine shop.

 

[Ross Nicol]

Russ
I've just got back from the machine shop and I measured the depth of the threaded holes at 1.5" from the deck to the cup shaped floor of the hole. I used a push rod for the measurement so it's pretty accurate. Now an important point is that there is no rebate or countersink on the deck of the Dart block to allow the stud to go further into the hole and in comparison on the stock block there is. Not just on the two dowel studs but on all others too. If a rebate was machined into the Dart as in stock block it is likely the bullet at the end of the studs would bottom ok. I did get the impression from Adam (one of the machinists) that this is something they do. Maybe Jac Mac can confirm this. Having said all that Adam described some blocks that have been in for machining having alloy spacers under the studs and how they had blown out when air gun used for cleaning. I've measured the head thickness on both Edelbrock vic jnr and Ford racing heads at approx 35mm thick on the short stud flange. See if you can get that measurement from your brodix heads.

Ross

 

[Kevin Box]

Uncut Brodix Track1 is 34.5mm

 

[Ross Nicol]

Ahh thanks Kevin be interesting to learn what Russ' heads measure. Hopefully we can get to the bottom of this one before Russ reassembles his and I assemble mine.

Ross:thumbsup:

 

[Jac Mac]

Yes, you need to remove the top couple of threads to same depth ( but not as large in dia )as 'Dowelled' corner bolts as per dwg so that correct studs can be fitted with bullet/machined end as shown.

 

[Ross Nicol]

Thanks Jac Mac this makes a lot of sense and Russ will no doubt find your info helpful too. It's a bugger when you're not in the loop with these things sometimes. Sorry I couldn't make it down to see you this year but pressure of work and so far behind with GT40 engine, you know what it's like. Say hi to Donna for me.

Cheers Mate
Ross :thumbsup:

 

[Kevin Box]

Ross

There are 2 engines in my workshop which are candidates for the 40

1 302 truck block which is about to get 347 scat 9000 / JE pistons
2 351 W built with 6.58 rod combo

Piston height is almost the same with pin in the oil ring area for both cases and both already set up for hydraulic roller so really the block is the difference ??? 8.2 vs 9.5 ???

Considering a the hassles you are having with blocks and all the adverse comments etc I must admit I am starting to think of going for the 351W. I could look at 393 or bigger at a later date if if I did.

This is bound to get some comments !!!

regards

Kevin B

 

[Russ Noble]

Well here we go Ross...

My heads at the outer studs are 38 thick, holes in the block are 39, gasket 1, washer 3, nut 13. Total 94. Stud length of the 154-4203s is 82 so it will have insufficient engagement in the nut by 12mm if the stud is bottomed out. I actually made some 11mm spacers to go down the hole first for the studs to bottom onto.

For the inner studs my heads measure 76, so total 132. The studs are 127 so a 5mm shortfall there

Ross, your heads are 3mm shorter but you are still going to be 9mm short on the outer nut engagement. Maybe a 3/8" ball bearing down the hole? Or use the Dart studs 66130121? Or maybe ARP can supply something in the right length?

Just waiting for the Dart studs to arrive.....

Didn't go down to Levels in the end, family things to do, but I heard JO's TVR disappeared in a cloud of smoke, never to be seen in anger again.....Can't have been Jac Macs long rod motor or his diff, so he must have split the gearbox and poured oil all over the exhaust......

Sad to hear about Dave Brown (not the one of CCD fame)

 

[Jac Mac]

Didn't go down to Levels in the end, family things to do, but I heard JO's TVR disappeared in a cloud of smoke, never to be seen in anger again.....Can't have been Jac Macs long rod motor or his diff, so he must have split the gearbox and poured oil all over the exhaust......

Sorry Russ, but looks like JO's TVR will live to fight again, although after six or seven seasons now ( Sorry, I would have to look that up) on the same components I wouldnt be surprised if it needs a bit of TLC......... the smoke was due to a simple problem that could have had a much more serious outcome.... one which I ..might.. explain in detail @ a later date so others can avoid the same . I know I wouldnt like it to happen to me either as a driver or crew member. One good thing that has come out of it all is that a crew must keep everyone informed of what they are doing or have done & why, without that your screwed.

Oh, I see Kevin fishing for a comment in the previous post, I wouldnt give two cents for the 347 if its the 3.4" stroke/5.4" rod combo,
But the 3.5" stroke, 6.58" rod, 1.165" pin height 351/9.5" block deal gets my total seal of approval

Oh & I have a 393... its going in my F250... about the most suitable application for it

 

[Kevin Box]

Thanks JacMac

351 was initially built as a jet boat engine
Rods are 400M narrowed at big end and bushed top to .927 (uses Cleveland bearings)
Pistons are KB276 hypereutectics
Block is zero decked and has a cradle in the bottom.
Runs hydraulic roller 228 @ 050 and 530 lift.

The more I think about it the more I am inclined to go 351 even with the additional weight.

KB

 

[Ross Nicol]

Oh well I have the combo that Jac Mac wouldn't give me 2 cents for, but I have a history of selective deafness with my mentors. Yes it has bought me undone in the past, but I'm prepared for the possible consequences.
Russ I have some 7/16 head studs here and the short ones are 82mm as per your 1/2" ones. I agree they are too short to bottom in the DART block. Can you let me know how the Dart studs go when you get them.

Ross:thumbsup:

 

[Russ Noble]

Will do Ross.

As of tonight, still waiting.....

It's a bugger when you can't just walk into your local speed shop and compare parts off the shelf.....

That's the disadvantatage of a country with a small population on the other side side of the world from where it all happens.....

Not withstanding, there are more positives than negatives to life in Godzone.....

 

[Kevin Box]

Russ

Maybe Lim needs to build a machine to do rolled threads
Then you could make studs to whatever length you wanted ???

Just kidding

Not sure Aus is any better to find bits !!!

Hope everything else is well with you. I guess you're getting on to all the tidy up bits ???
Yeah Right !!!


regards

KB

 

[Russ Noble]

I guess you're getting on to all the tidy up bits ???
Yeah Right !!!
regards
KB

Yeah right!

How's this for a teaser? The blue stripe! Wasn't going to do this until the winter rebuild, but since I had to attend to the damaged panelwork front and rear it seemed a good time....

 

[Russ Noble]

Studs arrived today. All OK. They snug nicely into the bottom of the holes and are slightly longer than they need to be. About 5mm overlength on the shorts and 10mm on the longs. I think these are what you are going to need Ross.

First two pics compare old and new, last two show them installed.

I have been doing a bit of reading about torque values and by all accounts it is hard to get reliable and repeatable clamping forces using a torque wrench due to frictional discrepancies. The preferred method where you can't use a stretch gauge is torque angle, but unless you know the amount of compression you are getting in your gaskets etc you can't do it.

However it is stated that if you torque your nuts up and release them about a dozen times with your preferred lube and take care to retain the same nuts on the same studs they will burnish the threads and provide relatively equal and repeatable clamping forces. Sounds logical to me, I think I'd use the old head gaskets whilst doing that and fit the new ones for final assembly.

This annoying but minor motor problem is just the result of a lack of experience on my part in building a moderately high performance V8. I simply missed the boat on a couple of simple issues. Many might say if I'd had a reputable builder do my engine I would not have had these problems. That is probably true, but then I would have been quids out of pocket and wouldn't have learnt anything either!

This whole GT40 build has been something of a journey into uncharted waters for me. Lots of research and learning and then applying it....not always successfully.....

Just waiting for the head gaskets now........

 

[Russ Noble]

Well, the gaskets arrived yesterday after delays with the suppliers and they were also held up for a few days by Customs. So I've now finished putting the motor back together and Lim and Leon came round tonight to help with getting it installed in the car. The majority of the work is done now, just got to fit the rear subframe and hook up fuel, electrics etc. Then fire it up and load it up tomorrow night, ready for an early start for racing the following day.

Another OSCA race weekend where I am totally outclassed but there is one reverse grid race which won't make a lot of difference and one handicap race which could be a bit of a laugh. As well as qualifying and a scratch race.

In the scratch race where I'll probably be off the back of the grid I'm going to try taking off in 2nd gear, 1st is useless, it just breaks into wheelspin. Could be tricky but interesting.....Effectively a 92 mph @ 6500 defacto 1st gear!

I am also trying out an extra bleed/bypass that I have plumbed into the cooling system in an attempt to get the engine water temperature up by means other than blanking off the radiator. I have different sized orifices that I can fit in the bypass and quickly and easily change to achieve the desired temperature. Pics later. However this is only an interim stop gap measure as later on I will be incorporating a bypass thermostat into the system. This should be the ideal setup provided the thermostat is reliable (I have an aversion to thermostats in race motors!) but I will have to alter the plumbing a little and make up a remote housing for it also.

 

[Keith]

I have different sized orifices that I can fit in the bypass and quickly and easily change to achieve the desired temperature.

Washers? That's what I always used. Very simple & effective with differing I/D's depending on conditions. I agree, thermostats suck.

Good luck mate - fingers are crossed for you...

 

[Russ Noble]

Well the car nearly changed hands last night.

About 1 o'clock this morning Lim offered me twenty dollars for it. I was nearly going to take him up on it until :idea: I realised I could get $300 just by putting it through the crusher! :lipsrsealed: I think he was trying to take advantage of me... :furious:

 

[EGLITOM]

Russ

What happened ? After reading your post from 18/3 i thought by myself that this is a pretty dense timeline.
Don´t put to much pressure on yourself. You have built a great car, it would be a petty if all this small, but realy not uncommon things at least for a racecar, would
negate the fun you have had building the car and the fun you will have once the bugs are solved

hang on there
TOM

 

[Lim]

Well the car nearly changed hands last night.

About 1 o'clock this morning Lim offered me twenty dollars for it. I was nearly going to take him up on it until :idea: I realised I could get $300 just by putting it through the crusher! :lipsrsealed: I think he was trying to take advantage of me... :furious:

Russ remember ..... F O R D .....
Twenty dollars is a good deal :thumbsup:
you can still race it and polish, just like Logan doing :lipsrsealed:
Do not put too much pressure on yourself, have a good rest . Will check it again tomorrow.