Wow, a lot has happened in the last 3 years since I notice I've updated this site.
I'll summarise and provide photos..... First up, the car toured Tasmania in early 2022 with my local Mustang Club. It ran beautifully, had a session at a race track and otherwise behaved itself over the 700+ km distance tour. This was important as I had my wife with me!
- Remember to take your rev limiter off - for which i need my laptop to do, and i didn't bring it with me. D'oh!
- Seven year old (hard compound) road tyres are next to useless! I even tried a set of Group A wet weather tyres (see photo above) but had the same issue - no grip.
- Make sure your new Tremec TKX shifter-stub is tightly bolted to your gearstick. I went from 1st to 4th on my final run as the TKX "sprang" itself back into the central (3rd to 4th) shift plane via my loose gearstick (must have rattled loose driving to the event).
I got a best of only 13.40 in the (sometimes wet) conditions. So there is lots of room for improvement. But that needs to come from the start, which is tricky with road tyres and rear-wheel drive only.....
Third, in early 2023 I got a lesson in trying to "do things on the cheap".
I had a roller lifter collapse and damage a roller cam. So I spent big $ and got a new cam, but just kept using my pool of existing Comp lifters (as I had a couple of sets). But they were obviously past their use-by date because once back up and running, a tie bar on a pair soon snapped with these lifters turning sideways and damaging lobes on the new cam. Ouch!!!!
Anyway, I grabbed a new set of Crower solid rollers (offset Inlet seat), sent the damaged Comp Cam off to Crow Cams (who are local to me) for repair, and did a full engine tear down.
I found 2 scuffed bores where metal splashed up and got wedged between bore and piston. Major bummer. I also noticed some slight movement of the Comp lifters in a couple of lifter bores. This may have been my problem causing lifter failure and would also be a factor in allowing lots of oil in the block valley at high revs - which i occasionally saw.
So what to do?.... After much research, I settled on a D.I.Y. bronze lifter bushing kit fron Wydendorf in the USA.
It comes with a self-aligning reamer to bore out the lifter bores, and a second reamer to "finish hone" the bronze bushing/sleves once they are installed. This photo shows the kit contents.
This setup lets me control oiling to the top end much better and of course renewed the lifter bores. Here is how the block ended up.
The 3mm hole was located (once the bushing was pressed into the enlarged lifter bores) such that as the lifter is on the cam base circle, this hole is just opened to the very top of the oil slot machined into the circumference of the lifter body. Then at full lift with the lifter at max height, the hole is still open, but now at the very bottom of the lifter oil slot. The result gives me 360 degree oiling to the needle bearings in the lifter. If you zoom into the photo above you'll see the oiling hole. I used a marker pen to align the bushings before tapping them into place correctly clocked. It was a bit fiddly to do all the measuring of oil gallery dimensions and lifter oil slot positions, plus dummy up the cam and lifter to verify....
Once the bushings were tapped in (and they tap/press in with a resistance a bit like cam bearings), i got the cylinders honed 10 thou' over to remove any scratches, got a new set of 40 thou' over Icon pistons (with domes machined for Trickflow A460 head valve positions), and then got the crank rebalanced - as the forged Icon units were 43 grams lighter each than the SRP's i'd been using. Ah - i also grabbed a new set of Eagle con-rod bolts as it seemed silly not to refresh them seeing I had torqued them up multiple times in all the previous dummy assemblies and subsequent inspections.
Next step of course was engine assembly, valve to piston clearance checking, decking the heads, etc, etc. Here are some photos of the short block assembled plus my "home handiman" way of decking/sufacing the Trickflow heads. Starting with a flat workbench, i layered two sheets of glass from my dads wine-glass cabinet down and secured them such that they cannot move. This gives as flat a surface as i could get at home in my car-port.
I then used some contact adhesive to stick 3 sheets of 800 grit wet& dry to the glass and once this had set, i liberally sprayed degreaser on top as lubricant. I then carefully lowered the heads onto all this and just shuffled the heads back and forth. I did this in 2 directions (90 degrees to each other) until i got a nice consistent surface. The photos tell the story of the results better than i can.
After assembly, i took the engine back to the dyno as i simply cannot bed new rings in with the engine in the car - it would just smoke the tyres trying to hold the engine under load and at low rev's.
We only did one dyno run after breaking the refreshed motor in, bedding in the rings and tweaking the EFI tune for the repaired camshaft. This cam is a bit of a Frankenstein actually.... The repair meant an inlet profile from one cam and an exhaust profile from a completely different cam was used. I lost 0.026" lift from the 0.726" lift (I and E) i originally had. Duration stayed pretty much the same, but the LSA was also tightend up slightly to 107 degrees. I used the "intake lobe centerline" method of degreeing the cam in this time too, to 105 degrees. The cam sheet itself is shown below.
In the end, here are the results as evidenced on the dyno sheet. This internally balanced engine is good for 7000+ rpm, but we weren't looking for ultimate power at this stage. I had the car booked in a show the following weekend, so i needed to wrap things up on the Friday right after we did this run. But you can see on the graph below how HP was still heading north at the 6250 rpm cutoff. In the few weeks since this engine refresh, I must say this car is awesome to drive.
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