• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

242GT 1979 Group C Race Car

Well things did not go as we expected. Unsure what the issue is yet but after running for approximately 30 mins and building up some lap speed temperature started to suddenly climb and started to blow white smoke. Unsure if we have done a head gasket or something more sinister. With our new warning devices we shut it down early and avoided cooking the engine.

As an aside it was interesting to watch the water temp increase much sooner than the head temperature but once the heat started to transfer the gap narrowed quickly.

We have pulled the pin on the next race meet and will go and spectate instead as all flights and accomodation paid for and non refundable.

The new target is end of April race meet to have it sorted.

For the time being car has been pushed to back of workshop for a couple of weeks until we get the time to pull the head and see what it reveals and remedy as our day jobs at present just dont allow for any days off before then.
 
Head pulled today and verdict in. Bottom end and head all good.

Issue identified as head bolts bottoming out in holes and even though tension spot on it was due to bottoming out and not to pressure on head. Trap for young players.

Solution simple and once we have head back on its off to dyno. Will be 3 weeks away at least. Next race meeting is last weekend in April so we will get some practice in before that too.

A shame but glad it was not more serious to newly refurbished pieces.
 
Tuff.

Yes stock head bolts and answer on how much shaving in total we don't know. We know its been skimmed twice and one of these was 26 thou but who knows what happened in the 30 odd years before it came our way. Good chance its had 3 .

I guess it would be useful to know virgin head width as reference for future and probably something we should know. Anybody know it?. Their 405 heads.
 
Well new head is on and car is tuned ready for shakedown. We have chosen to run with the H cam and the head has been flowed to handle just under 200 HP. We have to run CIS K jet and exhaust manifold so plenty of other bottlenecks before head will run out of steam. We have fitted an adjustable timing gear to help with setup for different tracks but for present have just set it at 1 degree advanced.

Would be great to be able to upsize the exhaust valve size at least but we cant so no point complaining. Head has been ported and fitted with custom manley valves with valve seats done to match.

In interests of sharing here are flow figures before and after head porting and valve choice etc. Before on left after on right. He wanted balance to be better but restrictions of standard exhaust valve does not assist at all. Note readings are at 10 Inches and I believe to convert to 28 Inches you multiply numbers by 1.67. Valves sizes standard

MUkKbcfl.jpg



Attempting to get car dynoed before shakedown to ensure we are not running lean throughout the range and to get a HP rating on the new setup.
 
Last edited:
Well Shakedown complete and all did not go to plan but we are ready to race at month end.

Engine felt very strong and had good drive out of turns. We also managed to keep welsh (freeze/core) plugs in block and all coolant where it is supposed to be. Running a good pipe and Oil pressure and engine temperatures all good.

About a third of the way into testing the engine would not fire after coming in to give it a check over. Traced it to a failed ignition module

And we thought no problem we carry a brand new spare in the trailer. Turned out to be the wrong one it was a later module 7 pin module so it was game over for the day. The good and annoying part is that within 5 mins of being home we had pulled one off our spare shell and fitted it up and car was up and running again.

Here is a video of the engine at idle and with a few revs after all the engine work and with a functioning module

 
Last edited:
Well Dyno run and done.

Car has 129.80 RWHP with maximum power at 6000rpm before it runs out fuel so we will change at 5700rpm normally. If we can get it some more fuel some hp still to be unlocked.

Have found a K Jet expert that can tweak a Porsche 924 distributor on the bench which is a straight bolt up swap to increase fuel flow. Will do some more homework before doing.


Now will give the car a good bath and prep for Race meet in 2 weeks.
 
Last edited:
95rwkws isn't a bad effort given the engine had 130hp stock! Especially given a stock turbo with auto is that sort of power... Look forward to seeing it in Melbourne some time!
 
You must log in or register to reply here.
Back
Top