how's your throttle body
- Thread starter jlat
- Start date
BRAD_PADGETT
Well-Known Member
- Joined
- Jan 22, 2004
Tests have already proven bigger throttle body does not make more power. I simply got a ported stock one that went from 57MM to 62MM. Don.t throw money away on a 70MM throtle body unless you like the look. Look up the old posts.
- Joined
- May 28, 2001
Refer to post #3.
- Joined
- Jun 9, 2013
When I did my motor last year Steve Monroe was Retired so I put on the polished Accufab 65mm and Precision polished plenum and I see zero difference.I knew I probably wouldent I just did it for the polished look.
- Joined
- Sep 21, 2018
only thing they are good for ....is they are extra sexy 
...if you like that kind of thang
...if you like that kind of thang
- Joined
- Jun 9, 2013
So does the 65mm it’s a 3 inch Coupler
TIMINATOR
Well-Known Member
- Joined
- Jan 26, 2020
IMHO, the more alky you spray, the better the alky distribution will be in the manifold.
The air out of the 70mm TB will be moving slower than a 62mm.
The air / alky has to turn down 90 degrees into the plenum from the TB.
The air then has to turn another 90 degrees into the ports.
Alky is much heavier than dry air.
It cannot turn as fast as the air does.
The alky HAS to stack up in the back of the manifold.
The reason the dyno doesn't see a HP difference is because the "happy" tuning range on alky is many times larger than gasoline, so the air/alky ratio doesn't make much difference. But it is there, the difference in air/alky ratio from front to rear cylinders.
If you can make enough HP by throwing more boost and alky to the motor, then don't concern yourself with this. If you want to make more HP with less boost and alky, then there is HP left on the table.
Since I am an old analytical bastard that has lived on a flowbench for over 40 years, I have done some experiments with stock and ported TBs, as well as the 70 that I have on my car.
I took the output from my flowbench and ran it thru a combo of TBs, up pipes and required reducers. I measured the differences in flow in the runners individually with each combo, with and without the correct port plates for the combos.
Then I added flowing alky too. Yeah, it was messy all over the driveway, but even without measuring the flow, I could see that there was more alky coming out of the rear ports.
To each, his own thing.....
I don't race anymore, but I run a 70 on my street car anyway.
Mebbie I just over think things.....
TIMINATOR
The air out of the 70mm TB will be moving slower than a 62mm.
The air / alky has to turn down 90 degrees into the plenum from the TB.
The air then has to turn another 90 degrees into the ports.
Alky is much heavier than dry air.
It cannot turn as fast as the air does.
The alky HAS to stack up in the back of the manifold.
The reason the dyno doesn't see a HP difference is because the "happy" tuning range on alky is many times larger than gasoline, so the air/alky ratio doesn't make much difference. But it is there, the difference in air/alky ratio from front to rear cylinders.
If you can make enough HP by throwing more boost and alky to the motor, then don't concern yourself with this. If you want to make more HP with less boost and alky, then there is HP left on the table.
Since I am an old analytical bastard that has lived on a flowbench for over 40 years, I have done some experiments with stock and ported TBs, as well as the 70 that I have on my car.
I took the output from my flowbench and ran it thru a combo of TBs, up pipes and required reducers. I measured the differences in flow in the runners individually with each combo, with and without the correct port plates for the combos.
Then I added flowing alky too. Yeah, it was messy all over the driveway, but even without measuring the flow, I could see that there was more alky coming out of the rear ports.
To each, his own thing.....
I don't race anymore, but I run a 70 on my street car anyway.
Mebbie I just over think things.....
TIMINATOR
Tim when you flowed your 70 with alky did it have a air distribution plate on it?
And when you flowed the smaller throttle bodies
Was the appropriate plate on those as well?
As their are different designs.
Flow bench simulates what kind of air speed?
The weight of alky should be dependent on atomization and the amount of alky sprayed I from what I have seen.
Was your testing through the varies throttle bodies with the same amount of gph through them?
When we pull the plugs with the rjc plate
They are uniform
Even with 50gph going through the top of the motor with 2 pumps and 4 nozzles
TIMINATOR
Well-Known Member
- Joined
- Jan 26, 2020
One pump, two nozzles, with and without the plates. Stock, ported, and 70 mm. TBIs. Distribution was better with the plates for sure.
That all gave me a few ideas for manifolds that didn't need port plates, but I sold both dynos when I quit racing and I figured that the Buick niche market would never payback the development costs or time.
I also like the idea of the larger 70mm sized upper. I believe that making a plate to adapt the smaller TB, in a different attitude with proper flow enhancements will be better yet. I don't like the idea of what the flow rate is on opening with the stock TPS and no adaptive electronics with the 70mm is doing to the programmed fuel curve. I believe that it's tunable to some degree with my Axis system. I need to calculate opening angle to flow rate differences to program the computer correctly. I believe an aftermarket computer would do a better job there.
Meanwhile, once I get my combo sorted, and parts made, I'll dyno it somewhere and see if it's worth playing with.
But I do like the 70 because the lack of transitions from the SLIC keeps turbulence down in the up pipe and t body reducer. I am making a better transition setup too.
I gotta do the tuning first with what I have on there now.
TIMINATOR
That all gave me a few ideas for manifolds that didn't need port plates, but I sold both dynos when I quit racing and I figured that the Buick niche market would never payback the development costs or time.
I also like the idea of the larger 70mm sized upper. I believe that making a plate to adapt the smaller TB, in a different attitude with proper flow enhancements will be better yet. I don't like the idea of what the flow rate is on opening with the stock TPS and no adaptive electronics with the 70mm is doing to the programmed fuel curve. I believe that it's tunable to some degree with my Axis system. I need to calculate opening angle to flow rate differences to program the computer correctly. I believe an aftermarket computer would do a better job there.
Meanwhile, once I get my combo sorted, and parts made, I'll dyno it somewhere and see if it's worth playing with.
But I do like the 70 because the lack of transitions from the SLIC keeps turbulence down in the up pipe and t body reducer. I am making a better transition setup too.
I gotta do the tuning first with what I have on there now.
TIMINATOR
