throttle stop motor on dyno question
 

anybody dyno there supergas motors with stop on motor-wide open of course? then take the stop off to see the horsepower loss incurred by having that restriction on the motor.

Re: throttle stop motor on dyno question
 

Never on dyno but I always took my under the carb TS off to run Q16 with my SC dragster It would run 3-4 hundredths quicker.

Re: throttle stop motor on dyno question
 

My friend did.....and on Q-15 which is a 50-50 mix of Q-16 and a std fuel that I don't recall what fuel that is.....

His 582 with a Sunset Plate stop (tapered bottom) vs no stop was about 20-30 hp difference....IIRC....over 1000HP with and without the plate...

I borrowed his stop and won a race with it and also ran Q-15 for a while myself....

Re: throttle stop motor on dyno question
 

VP C-15 is a 50/50 mix of C-16 and C-14. Q-16 is an oxygenated fuel.

Re: throttle stop motor on dyno question
 

Q-15 is a mix Gary Stinett supposedly tried and is what I was referring to.

A 50/50 mix of Q-16 and a non oxygenated fuel. I just don't recall what that fuel was.....C-14 or C-16 ...or ?


My buddy ran it for a few seasons and won numerous races with it.

His carb was calibrated for it.....and dyno'ed with it.

I ran it for a while and just upped my jets a few sizes.

It ran fine and is worth a solid 2 MPH...

Our friend and VP dealer supplied it to us at the races....

Very offensive fumes and I was more than happy to stop using it.....

You definitely know when your handling "funny gas" as someone once called it...

Re: throttle stop motor on dyno question
 

Q16 + C15 = Q15

I used it and we still run it in one car, works well as long as you're tuned up properly.

Shawn

Re: throttle stop motor on dyno question
 

My 468 that I ran many years ago was about a 670 hp piece, and it lost 7 HP on the dyno with the stop installed vs a 4-hole spacer of equal height.

Re: throttle stop motor on dyno question
 

We dynoed my SG 565 on C-14+.. with and without the throttle stop on the motor changed the power by 20hp average.. needless to say, going back to an inline stop...

Re: throttle stop motor on dyno question
 

Charlie I would not do that myself.....

Trust me when I tell you an inline stop is way more likely to cause your car to not run the number you expected it to....

Yea I am sure some people have had success with one and I won races with one myself , but overall a plate stop is a better choice.....

I tried various inline stops, changed cables, adjusted everything and looked for variations many times......different fuels......all the same result......occasional runs not where they should be and usually at the worst time.

I switched to a Plate stop.......2 different models......air operated.......and none of those issues.

I also am running more MPH than ever and using a plate....and on Sunoco Red or any other std fuel.....like X-16

Inline stop is good for bracket racing.....starting line control.....

I had both on my car at one time and could switch back and forth.

Took inline off and threw it in a Box..... A Plate stop for the win.....LOL

Re: throttle stop motor on dyno question
 

Couldn't agree more, Rich. I use an inline stop with mechanical injection as you used to do. If I bring it all the way back to idle on the stop, it is good. I've tried carrying some RPM down the track, and it is all over the place.

The plate stop under the carb on my door car is very good.

I would gladly give up 20 hp for the stability a plate stop brings.

Re: throttle stop motor on dyno question
 

All good info, Rich, and I'm sure that a plate stop would be more consistent because of variables involved.. however, when I installed the #1 Stop on my combination, I lost 3 mph.. I've been told that this is a common occurrence.. you're the first to tell me that you picked up..

I plan to do more bracket racing than .90 racing, and decided to switch back.. and not to mention that a recent manifold change, to the one YOU suggested that is supposed to be 3 mph better than what I had, left me with not enough clearance to put the plate stop back on.. but I did just learn that Sun Coast has another hood for my 27 Roadster, with a taller scoop... and Edelbrock does agree with you, as do many others.. THNX RICH!!

I'm only planning on 4 Divisionals this season, and only 1 National, as I have a credit from last season.. otherwise, you would not see me at a National Event...just sayin'...

Re: throttle stop motor on dyno question
 

Charlie it always takes trial and error on this stuff for sure as you know.

I did not pick up MPH just from changing stop styles.......The intake change for me was the gain....and I don't think I a plate slowed me down much.

My best MPH in stop racing was with injection and an inline stop....Virtually NO loss of MPH

A dragster obviously is very easy to swap intakes, spacers, stops with no hood issues......

Pretty much anyone you talk with has varying results with different equipment.....

If I was crossing back and forth from .90 to bracket racing I would probably run a Ron's Terminator as I have in the past and work on a better .90 setup....

Have fun wherever you race .....why else do it....LOL

Re: throttle stop motor on dyno question
 

You're right, Rich, and hopefully I will have the results that I have figured on.. I've talked to several people about the manifold, and have received the same results that you provided, so I think that will be a MPH plus, along with the inline stop, that should return the 2 or 3 that I originally lost... BUT, this stuff is all in my head.. we'll see what it actually does at MG this weekend.. hope to run into you soon...

Re: throttle stop motor on dyno question
 

Charlie I will be there tomorrow afternoon probably.

Usually parked along the tree line in the lower 40 or somewhere down that area.

Weather looks good and it's still one of the best places to spend a few days at for a race.

Re: throttle stop motor on dyno question
 

What about a disc stop? I can't see any reason for a HP loss with that. It basically acts like a four hole spacer.