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9 Second 1/4 mile runs this weekend with the Twin Engine GTP !

TwinV6GTP

TwinV6GTP

New member
In the heat Sunday, 93F + Humidity !
Two bone stock engines, two stock trans.
One from a GTP on from a Cadillac. 1000$ worth of drivetrain !


I was shooting for 9.4 and I added 6-7 psi of boost in the rear engine. But I overboosted off the line at 20 psi in the start line.
Hurt the 4t80e Cadillac trans. I will be more careful and add a boost limiter for launch mode to prevent issues like this.

Regardless we had a lot of interest for the car, lots of people came and looked at it and were completely amazed at the complexity and also the success of the project.
Just one look in the cockpit and they all say.. how do you even drive this thing ?? lol.
 


OMG this car is bonkers! Id love to see this thing in person! Getting shot out of a cannon has new meaning with this thing! HAHA needs half mile or mile run......
 
Car was super stable. Launched in 2nd gear as you guys can see. On both engines. The track was pretty sticky, I think I should have left 1st gear on the rear engine.
Next time I might try that.
 
1.50 60 foot
1.8 0-60mph
4.4 0-100 mph

It ran a 1.48 60 foot on another track in cooler weather.

I think it can launch much harder I'm shooting 1.3s once things are fully dialed in.
 


459996.jpg
 


BillBoost37 said:
You say it hurt the 4T80?
Click to expand...
Yes we hurt it...
2nd gear start too much boost 20 psi on the torque converter. The stock 4t65-hd on slicks in front still alive.
We will have to be more careful and limit torque off the line.

It is much stronger than the 4t65-hd... but not 200% stronger.

The failure doesn't seem to be a typical breakage of the 4t65-hd. Not the input, not the chains.
It seems related to the shift mechanism. It's like it popped out of the gear and slammed back in. But that bent something.
Whenever I apply good torque it falls in neutral or starts slipping.
I lose reverse or drive at different times now. It still runs and drives. It shifts all gears.
It just can't take the torque anymore.

James thinks it's related to a clogged filter and line pressure loss. I think I bent something in there, not pressure related.
We'll have to open it to see what's up. I will be running an Aurora torque converter next to reduce the torque load at low rpm.
It should allow more slip and not stay in the high torque danger zone as much as this super tight 4.6L converter.
 
I haven't gone inside of an 80, but in a 65, there's no way to bend something that will cause a slip when you aim for power. Fluid is diverted and that's how most of these transmissions shift. Which would put you at a clogged filter/pressure loss to make sense. It's possible you did hurt something that blew a lot of crap and the filter picked it up. Sounds like a pan drop is happening automatically since you'll be pulling it anyhow.

It'll be interesting to see what happened.
 
I saw how long you had it on the converter. .. cant stall em that long....
After 3 seconds your turbine pressure is already dragging the tcc and dumping a ton of heat into the converter/fluid.
on our fully built 65 e the torque converter clutch pressure is set to max on both release and apply and we were still cautioned not to go on to the converter for more than 3 seconds.
it may be that you killed the forward sprag...but I'm going to lean towards the clogged filter being a primary issue. that sprag is not known to fail...it may well be that you have the boost valve issue and you're not getting nearly as much pressure applied should but even then that would boil down to possibly being the filter oil pressure you too.
keep in mind it could be the turbine hub sprag
 
this would be a whole hell of a lot easier to figure out if you had the OEM PCM controlling it and were able to data log the trans sensors.

I'm not saying... I'm just sayin...
 


I stumbled on videos of this car recently & I love it! Impressive piece of engineering. You did an awesome job. I wonder what you'll do next?
 
We are taking it to an airstrip and run 1/4 and half miles against many cars and bikes. Well set up the video vbox and go pro cams should be a hoot


Sent from my iPhone
 
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highoctaneracing said:
I hope you break ZZP's record. I bet they'll sh!t their pants lol
Click to expand...
ZZP's record will be difficult to beat with the current mindset (stock parts everywhere).
Their car was a true full out drag car, extremely light, ultra high RPM 3.8 high boost etc...
Beautiful build with a huge budget.

With 20K in parts plus our time, I think we can beat that time. And if we succeed, it will be on 1/3 of the budget.
 
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