[TCSGTO]

Just got some of the videos my buddy took a couple of weeks ago uploaded to YouTube. Slowing them way down I can see the front bouncing and unloading the rear tires past the tree. Better shocks and maybe limiting front end travel slightly may help at this point.

We went back last week and traction was non existent. It had snowed and rained the day before and the track was in terrible shape. As soon as the throttle was pressed the engine was at redline about 10’ out. Made 2 passes and called it quits before I wadded the car up against the wall. Best was 11.43 @ 125.89 with a 1.87 60’.

https://m.youtube.com/watch?v=RKIyBu-BpiU
https://m.youtube.com/watch?v=vHQVDBj5wl4
https://m.youtube.com/watch?v=lueuUvTKgnE
https://m.youtube.com/watch?v=GiZymFErFdE

[mchell]

What are you running for tire?.....looking like it wants to pull!

That trim ring flying off!.....wo

[TCSGTO]

Hoosier 275 drag radials. My first go round with DR’s. Like them better than the bias I always ran before.

[mchell]

Ran the Hoosier’s at one time....good tire

Running any air bags?

I’m seriously considering an anti-roll bar at some point....seems this would level out the launch dramatically

https://www.hrpartsandstuff.com/

[TCSGTO]

Originally Posted by mchell

Ran the Hoosier’s at one time....good tire

Running any air bags?

I’m seriously considering an anti-roll bar at some point....seems this would level out the launch dramatically

https://www.hrpartsandstuff.com/

I have the Spohn version of the bolt in ARB and no front bar. You really don’t need a front bar on the street with it since it keeps the car pretty flat around turns. I was worried it might limit weight transfer but that’s not the case.

I had the bags up until last year, they worked on launch but you had to have the pass side pumped up to where the car the really leaning at rest.

Probably will have to break down and get a good set of shocks at this point. Have a pair of 20+ year old worn out set of Lakewood 70/30 fronts and equally worn out Summit rears. On a good track it probably doesn’t matter but on a marginal surface it could use some help.

[mchell]

Originally Posted by TCSGTO

I have the Spohn version of the bolt in ARB and no front bar. You really don’t need a front bar on the street with it since it keeps the car pretty flat around turns. I was worried it might limit weight transfer but that’s not the case.

I had the bags up until last year, they worked on launch but you had to have the pass side pumped up to where the car the really leaning at rest.

Probably will have to break down and get a good set of shocks at this point. Have a pair of 20+ year old worn out set of Lakewood 70/30 fronts and equally worn out Summit rears. On a good track it probably doesn’t matter but on a marginal surface it could use some help.

Yeah.....my exact experience with the bags as well

Thought you might have mentioned you are running the spohn version In another post....is the spohn a bolt in unit?

Tough task trying to run street/strip vs all strip ....Always a compromise

Your 68 really moves out!

[ta man]

Nice feature about your slow mo video..is you can still slow it down even more with the video settings. What was the 60ft time on the videos..looks like it really digs in and wants to go.

[TCSGTO]

The Spohn is a bolt on bar. Sort of a rip-off of the H-n-R but it works.
60’ when it dead hooked we’re 1.47-48. When the trim rings flew off it hooked hard initially then spun and shook the tires. I think I need to slow down the front end rise and make the hit last longer.

[AG]

I would have to take the trim rings off at my rack.

[TedRamAirII]

The Tech Guy usually has you remove them, I have seen cars run them, like the Tech Guy forgot they were there. I would'nt want to lose one and chance damage. Seems odd that they can be there for years, and decide to exit the wheel!

[Half-Inch Stud]

Seems ya Knocked-off nearly 3 seconds going automatic. Good move, and even better to keep the 4-speed stuff in bags on the shelf.

Here's a unique diagnosis/thought: seems the Combo stop pulling 20' out due to the engine loading up, due to the Converter stall gonig away into 1:1, with the evidential being the front-end dropping back down.

Yet rather blame the converter, or suspension, i want to ask what the Total Advance was?..!
See im kinda sure my combo would do such with excess Timing. Yet would become a capable TQ&HP engine under load with 32-34 Total ADV. And of course would do poorly with 28 deg Total or less.

To promote a major arguement (and then the insightful discussion) with yout trans builder: the 1-2 upshift may be "catching Reverse" as I say, and i think to know how to avoid thaat.

[TCSGTO]

I thought I was getting to be fairly fluid in Studisms after all these years but I admit I don’t really understand the gist of the post, but I’ll play along.

I gained 3 seconds by replacing a stock 400 with a 517.

It stuttered going into 2nd not because it “caught reverse” but because it hit the rev limiter at 6700 RPM ( my bad). Carl Rossler built the t400, he’s built 1 or 2 before but maybe he’d be willing to learn something new if you call him.

Stops pulling 20’ out? Did it? If it did I missed it. If it did there might be a high 9 in it @ 130+ if it would have pulled for the full 1320. Or maybe it’s just a case of trying to funnel 650ft/lbs through a 10” DOT radial tire on 25 year old cheap drag shocks with 60% of the weight on the front tires?

Timing is 36 total, it made best power at 38 on the dyno but I’ll knock it back to 32 if it’ll make ya happy.

How’d I do?

Seriously,I think it did great for its first time out but it does need a few areas tightened up.

[Half-Inch Stud]

Yea, you did real fine. I was just poorly summarizing the engine swap.

All 4 videos show a typical front-end rise with subsequent fall. I suppose perhaps the issue is the front-end falls so soon after roll-out for such a large powerful engine.
The 3860 Lbs is not overlooked: that is a heavy load despite the excellent driveline.
Excellent 60foots so im going to focus on Converter & top-end MPH.

Coupla dumb Qs: Did you really hit 6700 RPM in 1st gear before the 60foot mark, in all 4 videos?
Was there really a 1-2 shift so soon before the 60foot mark?
Battery in trunk near the rear bumper?

Im certain you kept your foot in it each run. So, if the unload is early, then maybe an early 1-2 shift may help keep the converter in TQ-multiply range, and keep the engine less loaded. Imagine: when you hit Converter stall (right away) the car should roll while the Tach sits at stall ( for a little time) then the Tach climbs from 4100-to-6700 like real quick for the greater roll-out.

During the 4100-to-6700 rpm event, the Engine TQ is going up, then down (hp going up), and TH400 input shaft TQ is about 2.3x engine TQ @4000 rpm but only 1.1x at 6700 rpm due to Converter slip (Converter in/out rpm ratio) There is some engine rpm where the upshift will pull great because the Engine can fall back to a high TQ multiply. Theoretically just below 4000 rpm engine-side. Butt...the converter fluid dynamics are a reality.

In reality the Fluid momentum in the Converter does not like an abrupt rpm drop on the ENGINE SIDE. The Converter can play well with the abrupt load-change caused by the 1-2 upshift more than an abrupt engine rpm drop. Regardless, the engine rpm does drop with upshift but some converter will have a brief efficiency loss while other (tight converters) retain the fluid momentum. So some advice front the converter guy and seat time should dial-in better ETs.

May not be the converter, but i always like to assign blame there because most converters are craap, and the few that play well sustain a noticable pull in the 1-2 shift, and decent pull in the 2-3 shift.

Timing is a tuning variable for acceleration, and top-end MPH. Aluminum heads folks know better than I for what Total Advance will accelerate hardest, pull the best, and bring MPH. I hope someone can tell ya what to set it to, and then forget it.

Using +0.1 sec per 100 lb you'd be in the high 9's for 3100 Lb, so you're not far off. Seat-time to dial-in upshift events. ( Timeslip analyzings needed to figure if leaning-out from660-1320.)

I think you can dial-in upshift events to optimize the top-end MPH

[OCMDGTO]

TC, beautiful car and great first effort there. Love these real world street car builds, especially the track results.