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Alright then. She's back together on the workbench, for as far as I want to take it. Once I can get some assistance in the shop from the nephew and brother, we can stuff it back in and hook up the fuel and electric to it! Progress

Awesome, keep up the good work, cant wait to see it all come together.

woodsbuggy1 wrote: ↑Thu Dec 18, 2025 6:17 pm Awesome, keep up the good work, cant wait to see it all come together.

Thank you Sir. I'm hoping for a better showing this time. I'll keep you updated

I'm pretty determined to NOT grenade my motor from detonation.... again, this time. It's just getting too expensive

The NA motor was pretty happy with the timing set at 32 degrees BTDC. Now that I have proper turbo heads and a much tighter deck, I have backed NA/vacuum timing to 30 degrees BTDC. After some insight, I have decided to set a target goal for boost pressure of 10 pounds... eventually. At this point, I have set my boost retard timing down to 17 degrees BTDC at 10 pounds.

It's a lot of math, but my timing map might make more sense?

Am I missing anything glaring? Hints or suggestions?

Update: I spent boxing day afternoon in the shop, and with my wife's help, we got the motor down off the workbench and onto the new lift cart. We were also able to get the motor reinstalled into the buggy. Now it's details and tuning for the new turbo and heads.

Be well

Closer yet!
The "structural " portion is complete. It's not going to fall out. The oil system is complete, minus the oil filter. The carb and intake is complete and linkage/cable is done. Fuel line and turbo dump need finishing and plug in the A/F sensor.

It's in and running! Success! And this time it appears to be oil tight.

I set it back to the jetting that Car Craft put in it, rather than the jets i thought it wanted, the timing is set to 10 or 12 or something at crank and idle, advancing to 30 degrees all in by 2500 rpm. Now, mind you, it probably never got to operating temperature this morning, but I could still watch it go lean at idle and stall if I didn't catch it with the throttle. This is what caused all this heads, turbo swap etc. I'll keep you updated if I get the chance to drive it about.

That red muffler looks familiar.......is that a 3" exhaust???? I have that same muffler since it was the shortest one I could find. It takes the edge off but that's about it.

What rpm is your idle at???
Draw through has a long way for the fuel mixture to go and you could be experiencing some puddling of fuel if the air velocity is lower when at a slower idle speed.
It will show as a black cloud of smoke on blipping the throttle after idling for a time. The hesitation can be from the throttle plate being a considerable distance from the engine.
Your intake and turbo is setup up ideally in that there is really no place for fuel to get caught but you could get air/fuel separation from a cold intake wall and fuel droplets forming on the intake tube walls.
Try idling at 1100-1200 rpm or a little higher.
Take your time tuning it and don't go all boost crazy right off the bat. Keep it down to 6-8 lbs. boost and maybe a max of 25 degrees timing at 8 lbs. boost. Work the timing up or down from there and listen carefully for detonation.
Draw through has an advantage in that intake temps will stay low due to the cooling of the air through the venturi effect but it only goes so far.

Hi CB. The exhaust was... "inspired" by yours. A couple of bends and a "muffler" from Summit, and drop them off at the muffler shop.

It doesn't actually "idle" yet. I've only started it the one time, and if I didn't keep feathering the throttle, the A/F gauge would show it going lean and stalling. I just need to be patient and let it get up to temperature, and maybe then, a stable idle can be achieved.

Right now I believe I have the boost set at 5 pounds max. I'm still a little gun shy after the previous events and I'm currently pulling 1.3 degrees per pound of boost.

Thanks for checking back in on my progress. Much appreciated

Mid week update and happy new year!
Working on the possibility that the lean idle and stall was based on an intake leak, I squeezed down on all the charge pipe hose clamps. Whodda thunk there's actually a torque spec for hose clamps? I had no idea, and I was a little shy of the value. I now have properly torqued hose clamps!

It also occurred to me that some additional timing at idle might help keep the idle up. I still have max advance set to 30 degrees, and I now get there by 1800 rpm rather than 2200 rpm. I also added a slower ramp up from 800 rpm up to 1200 rpm. It is making small steps towards improvement. It doesn't fall off so fast and once warm, it'll "idle" about 1500ish rpm!

Also, prior to this morning, I didn't "know" that my map sensor was actually communicating with my MSD box. I'm working by myself, so I screwed the idle up to about 2000 rpm, where the advance is all- in and applied air pressure to the map sensor. The laptop display showed that it was, in fact, working and communicating with the MSD box, and I could hear the motor idle down as artificial boost was applied!

I think if the weather warms up a little bit, it'll be time for a boosted test drive and a celebratory adult beverage!

Be well and enjoy your festivities!

The Venturi effect will make your intake temps really low when not on boost.....low enough to cause fuel separation issues and puddling.
I have read there can be a 100 degree temp drop with a carb venturi. That is enough to cause freezing of the moisture in the air and that might give problems.
Each turbo design has it's own issues and challenges. In order to make it a fun and reliable driver you have to be able to work through those.

Blow through gives you warmer air due to the turbo heating the air a bit just from the transfer of heat from the exhaust.....that is an advantage in cooler weather and cruising.
Your idle will have to be higher and I recommend around 1300-1500 rpm to start. Once you get it warmed up and the idle mixture right you can work on changing that.
Bump timing cold to 15 -18 degrees until it warms up if you can adjust that and once warm go down to 12-15 degrees.
Set your idle AFR for around 12.8-13.3 and adjust from there after getting some time on it.
Boost AFR should be 12.0 maybe 12.5:1 and adjust from there also.

The only issue I see is if the idle is that high you might be running slightly on the transition circuit and that might cause problems with your AFR readings.
Best to get it good and warm and adjust idle AFR at as low an rpm as possible...then raise rpm to get a comfortable driving experience.