Type 65 Straight Line Performance Capabilities

[gtrclark]

Hi All,

I recently sold a high horsepower Nissan GTR and I’m considering buying a Coupe that my Uncle built. He built it very simple and I’d be looking to heavily modify the powertrain to chase down some extremely quick 60-130mph times. My question is, is there any data out there on 500+whp Type 65’s and how quick they are in the 1/4 or 60-130? Any information is much appreciated.

Thank you!
Mike

[Suzie coupe]

Hi All,

I recently sold a high horsepower Nissan GTR and I’m considering buying a Coupe that my Uncle built. He built it very simple and I’d be looking to heavily modify the powertrain to chase down some extremely quick 60-130mph times. My question is, is there any data out there on 500+whp Type 65’s and how quick they are in the 1/4 or 60-130? Any information is much appreciated.

Thank you!
Mike

Isn’t that answered with math? Should be able to get a close estimate, I’m no engineer so I don’t know the math but 2400 lbs + 500hp = ? Approximately. Of course you need to be able to put it down, but it’s an easy car to put massive tires on that will help it connect.

[RoadRacer]

yep, plenty of 'quarter mile calculator" results to go through, e.g. https://xcceleration.com/et.calculator.html

500+2400 = sub 10sec car

[Glen Davis]

Here is another estimate calculator https://robrobinette.com/et.htm

[gtrclark]

Thanks guys. I’ve used calculators like that in the past and they are notoriously inaccurate. A little over 500 wheel in a Daytona should give about the same power to weight ratio as what I had in the GTR on pump gas. I was just wondering if anyone had a setup making that kind of power or more and had done some Performance tasting. I talked to my uncle today and I’m going to move forward with the purchase ���� I’ve loved the Daytona since the first time I saw it, looking forward to building a monster!

[RoadRacer]

When I think of performance 65's I think of John George (https://thefactoryfiveforum.com/showthread.php?26646-Type-65-driving-impressions&p=304250&viewfull=1#post304250) - his links may help

[Jeff Kleiner]

What generation of Coupe is it and what rear suspension? If it's a Gen 1 or 2 with the T-bird derived IRS the weak axles are going to be your fuse if you try to put down 500 on sticky tires. Check out Erik Treves' twin turbo Coyote powered Gen 3 Coupe; with 680 at the tires it goes pretty good...

https://thefactoryfiveforum.com/attachment.php?attachmentid=153295&d=1631484562

He stopped by the local 1/8 mile strip on his way home from work one afternoon and ripped off low 7s @ 100+ right off the street (didn't even take off his necktie ;) )

Jeff

153295

[gtrclark]

It’s a Gen 2 with a 3-link solid axle. Erik’s sounds like a great combo! I couldn’t find any other stats but 7’s at 100+ is good. I’d be very curious if that was traction limited. I’d like to see what these things can you do with serious tire. Can you fit a 28” tall tire underneath? I’d think with 650whp, depending on weight, that thing would be around 150mph or higher in the 1/4.

[jamminj]

easily with the right tire and properly tuned suspension you may need little more than 650whp to get there and very good control of both clutch and throttle
I'm going for a lot more than that

[jamminj]

the calculator isn't accounting for a stick shift blowing the tires off and shift time and only 11% parasitic loss. Bigger stickier tires use more power to move

[Erik W. Treves]

What generation of Coupe is it and what rear suspension? If it's a Gen 1 or 2 with the T-bird derived IRS the weak axles are going to be your fuse if you try to put down 500 on sticky tires. Check out Erik Treves' twin turbo Coyote powered Gen 3 Coupe; with 680 at the tires it goes pretty good...

https://thefactoryfiveforum.com/attachment.php?attachmentid=153295&d=1631484562

He stopped by the local 1/8 mile strip on his way home from work one afternoon and ripped off low 7s @ 100+ right off the street (didn't even take off his necktie ;) )

Jeff

153295

Thanks for the plug - yeah I literally was on my way home from work and noticed they were doing test and tune and happened to have the helmet in the car - we only have an 1/8 mile track here - anyway I only removed the speaker box out of the car and did a light burnout - first time launching the car was a 1.8 60' and was kinda in between deciding if I needed to shift into 4th before the trap - which I did - and the car gave up a little right there. The was the only run I did since I so wasn't dressed to play and didn't want to press my luck. The track prep was really good and I thought I was going to be traction limited but when I squeezed 2nd it stuck - anyway... I didn't even "launch" the car I think I left at around 1500 RPM (maybe)... there is why more in it. But a low 7 in the 1/8th at 101 mph - is pretty good with a complete street setup in it .... I have gone 2.9 Sec from 0-60 off the line lock starting in 2nd gear..... the chassis is strong enough that with a good setup my numbers would be considered the slowest it could go.... but even still - pretty happy to be able to have these numbers wearing my neck-tie.... I did flip it over my shoulder though (a la Red Baron)

just a light drive...


https://youtu.be/DpE9EOYD6IQ

[gtrclark]

Thanks for the plug - yeah I literally was on my way home from work and noticed they were doing test and tune and happened to have the helmet in the car - we only have an 1/8 mile track here - anyway I only removed the speaker box out of the car and did a light burnout - first time launching the car was a 1.8 60' and was kinda in between deciding if I needed to shift into 4th before the trap - which I did - and the car gave up a little right there. The was the only run I did since I so wasn't dressed to play and didn't want to press my luck. The track prep was really good and I thought I was going to be traction limited but when I squeezed 2nd it stuck - anyway... I didn't even "launch" the car I think I left at around 1500 RPM (maybe)... there is why more in it. But a low 7 in the 1/8th at 101 mph - is pretty good with a complete street setup in it .... I have gone 2.9 Sec from 0-60 off the line lock starting in 2nd gear..... the chassis is strong enough that with a good setup my numbers would be considered the slowest it could go.... but even still - pretty happy to be able to have these numbers wearing my neck-tie.... I did flip it over my shoulder though (a la Red Baron)

just a light drive...


https://youtu.be/DpE9EOYD6IQ

Looked smooth! Is that a T56 Magnum in the car? Love the flightstick **** knob! :-D

[Erik W. Treves]

it's a MT82 version 2 out of the mustang

[GoDadGo]

Question For Erik Treves:

You've built multiple high horsepower cars so is the 3-Link better than the IRS straight-line performance?

> The reason why I'm asking is my car, which is a 3-Link, seems to plant the tires a lot harder than my pal's IRS MK-4.
> He is running a 396 FE (.030 / 390 Ford) with 3.55 gears while I'm running a 383 SBC with 3.73's.
> His car is on Nitto NT-01 tires while I'm on the Nitto 555's, yet I stick these harder tires better.
> I think we are making similar power, but his car seems to spin more than mine.

Sorry to highjack this thread, but wanted to know E.T's opinion since he is an expert on these cars.

[egchewy79]

Thanks for the plug - yeah I literally was on my way home from work and noticed they were doing test and tune and happened to have the helmet in the car - we only have an 1/8 mile track here - anyway I only removed the speaker box out of the car and did a light burnout - first time launching the car was a 1.8 60' and was kinda in between deciding if I needed to shift into 4th before the trap - which I did - and the car gave up a little right there. The was the only run I did since I so wasn't dressed to play and didn't want to press my luck. The track prep was really good and I thought I was going to be traction limited but when I squeezed 2nd it stuck - anyway... I didn't even "launch" the car I think I left at around 1500 RPM (maybe)... there is why more in it. But a low 7 in the 1/8th at 101 mph - is pretty good with a complete street setup in it .... I have gone 2.9 Sec from 0-60 off the line lock starting in 2nd gear..... the chassis is strong enough that with a good setup my numbers would be considered the slowest it could go.... but even still - pretty happy to be able to have these numbers wearing my neck-tie.... I did flip it over my shoulder though (a la Red Baron)

just a light drive...


https://youtu.be/DpE9EOYD6IQ

The shirt/tie combo is awesome! I can't imaging the looks on the faces of the workers at track when you show up dressed like that :)

[NAZ]

Hi All,

I recently sold a high horsepower Nissan GTR and I’m considering buying a Coupe that my Uncle built. He built it very simple and I’d be looking to heavily modify the powertrain to chase down some extremely quick 60-130mph times. My question is, is there any data out there on 500+whp Type 65’s and how quick they are in the 1/4 or 60-130? Any information is much appreciated.

Thank you!
Mike


Mike, a 2500lb car with 500WHP and the right gearing will run in the nines on a 1/4 mile track with good air.

I really like the design of that car but if you live where your only drag strip is an NHRA sanctioned track you may find it a challenge to even be able to run that car as it most certainly does not comply with NHRA rules. NHRA tracks are supposed to enforce NHRA safety rules even for run what you brung events. Plus, you'll need an NHRA competition license to drive a car that runs quicker than 10.00-seconds or 135 MPH. That car may pass tech at those mile speed events held at airports around the country, but it'll take a significant amount of modifications to make it NHRA legal. I know because I'm one of only two people that have made a FFR car NHRA legal.

https://nationaldragster.s3.amazonaws.com/Rulebooks/2021_NHRA_Rulebook_21_01_28/index.html

[N2mini1]

Calculator is figuring a pretty much perfect pass. Gearing/tranny, tires, track, weather of course all play factors. Let along the one behind the wheel...

[Erik W. Treves]

Question For Erik Treves:

You've built multiple high horsepower cars so is the 3-Link better than the IRS straight-line performance?

> The reason why I'm asking is my car, which is a 3-Link, seems to plant the tires a lot harder than my pal's IRS MK-4.
> He is running a 396 FE (.030 / 390 Ford) with 3.55 gears while I'm running a 383 SBC with 3.73's.
> His car is on Nitto NT-01 tires while I'm on the Nitto 555's, yet I stick these harder tires better.
> I think we are making similar power, but his car seems to spin more than mine.

Sorry to highjack this thread, but wanted to know E.T's opinion since he is an expert on these cars.

I am not sure I am an "expert" - but simply comparing rear suspension design as a matter of performance isn't really going to be useful.... I would say from a complication , weight and strength / serviceability - I think the straight axle with a 4-link would be the "best" - for straight line based on weight transfer....

The comparison that you are making above doesn't take into account spring rates and shock settings - it's a game of weight transfer to plant the tires. I am getting 0-60 in 2.9 in the coupe with 1.8 60' at the track with IRS.... I was also getting 1.8x 60' with my mark 1 with a 3-link.... so I am not sure one is "better" than the other - I think it just depends what you are after from the big picture....

my "OPINION" is that the IRS gets you best all around performance and ride quality..... it will tend to do better at AUTOx as well (if properly set up)... where the live axle will have more adjustability to support the drag racer with SOME reduction in ride quality

Again - only my opinion.... so which one is better? it depends... the key is to make sure whatever you have - that it is setup correctly - that is the most important part.

[Skuzzy]

Opinion bursting forth
I could see an IRS having a shear moment at launch *IF* during weight transfer and torque roll there is a geometry shift (camber and/or toe in) causing the contact patch to shift from side to side, or pressure changes within the contact patch, from side to side. How much impact this could have might be negligible.

I think a 4 link/panhard bar with a straight axle is probably the best for straight line performance, or the most consistent as the 4 link will resist the torque moment and will never suffer from camber or toe in changes.
End bursting opinion

[J R Jones]

Three link vs four link?
A couple of months ago there was a thread on a Roadster with three link that was stable/straight until he laid down a 500hp launch and the car surges left.
NAZ got into the conversation and pointed-out that his four link live axle is stable launching with 1000hp. As noted above, his is an NHRA legal car at that performance level. optimized.
jim

[NAZ]

An IRS suspension configuration like the Mustang and T-Bird that has been used in the FFR cars is a challenge to optimize for straight line acceleration or braking -- just not the adjustment needed to really make it great. My new race car IRS is much easier to adjust as it has trailing arms. But the absolute best axle type for straight line acceleration or braking is a solid axle with a parallel four-link (not that triangulated abomination that the old Mustang and several GM cars use). It is by far the easiest to optimize and when set-up correctly, doesn't really give up anything to an IRS for roundy-rounders or the cone heads that like to run the SCCA Solo game.

[J R Jones]

In the seventies my partner and I were running SCCA BP with a Shelby and AS with a 1970 Boss 302. In both cases we had to run the live axle on leaf springs. Being curious we experimented with the live axles to find an advantage. The Shelby had a unique aftermarket leaf spring where the main leaf wrapped around the front "I" and back to the axle on top, to be clamped under the axle pads. That car never had axle tramp, but we were not drag racing. The Shelby also had a Watts linkage with the bell crank on a crossmember.
The Boss 302 had a simple panhard bar AND four track bars. To eliminate binding with the leaf springs, we floated the leaf to axle mounts with slotted clevis joints. Worked great and was rule book compliant. Three bar was never considered.
jim

154611

154612

[NAZ]

Jim, that must of been good times. It's very rewarding to design and experiment with race cars looking for any advantage to make your car more competitive. I have as much fun building them as I do driving them. I've learned so much over the last half-century of playing with race cars and race bikes and I'm still learning.

[64 COBRA]

What generation of Coupe is it and what rear suspension? If it's a Gen 1 or 2 with the T-bird derived IRS the weak axles are going to be your fuse if you try to put down 500 on sticky tires. Check out Erik Treves' twin turbo Coyote powered Gen 3 Coupe; with 680 at the tires it goes pretty good...

https://thefactoryfiveforum.com/attachment.php?attachmentid=153295&d=1631484562

He stopped by the local 1/8 mile strip on his way home from work one afternoon and ripped off low 7s @ 100+ right off the street (didn't even take off his necktie ;) )

Jeff

153295

Sounds like a monster w that power to weight ratio \:cool:

[NiceGuyEddie]

A little late to the party, but over the years I have learned that the horsepower / quarter-mile estimators are very accurate with drag slicks and automatic transmissions.

In any case, the good news is the tech at the track for the Coupe is easier, with my roadster the local tracks won't let me run faster than 7.5 in the 1/8th mile, and they will no longer let me run at all at the local 1/4 mile tracks. (Need to have full rollbar or dual rollbars for a roadster.)