Choosing Right Manufacturer - Long Question

[Sandy]

To put a bit of closure on this thread, went with an RCR GT40.

Went with the deluxe kit plus a lot of other stuff that I wanted that Fran was extreemly paitent and helpful sorting out my needs. My goal was a 1075'ish car with a modern treatment in many aspects of engineering. For tire fitment I went with 12"x17" PS BRM's and Gulf flares, Full Cage, and some other nice items.

The trans was my big problem, and given what motor I wanted to run it was either the Porsche 930 or Hewland NLT. I went with the 930 as I don't think a stronger box exist with out stepping up the extra 20k for the Hewland or other race box. If I blow the porsche box, it will be smashed with a hammer and I'll get the Hewland. /ubbthreads/images/graemlins/smile.gif I don't think I'll have a problem however. Powerhouse is doing the box, and should be very good. I may have mentioned that since it has only 4 gears instead of 6 I'm have much better odds at not blowing a shift /ubbthreads/images/graemlins/smile.gif

Motor project now can begin, which is the easy part (I hope). Likely to stick with 8.2 Deck Alloy block and related parts I'v hidden away from my wife over the years

Thanks so much to all the folks that offered with feedback and suggestions to helping me get from lurker to owner.

Sandy

 

[Chris Duncan]

"" One thing I notice is that many 40's don't sit right (IMO) They looked jacked up a bit in the rear, For example most CAV's I have seen (shows, photos) all seem to have this look (yes, ones with engines in them too, not to single them out in any way). I did find a thread that shows a few guys that tuck the tires in right, even with low profile 17's so I guess it may be just setup.""

You're talking about sitting up in the rear. It is just setup. When setting up ride height for the street which is typically 4.5" front 5" rear the rear fender lip will be well above the tire. At racing clearance which is about 3" front 3.5" rear the fender lip will be hugging the tire but you're not going to get over speed bumps.

Agree with Hersh 400 HP is about all that's usable in this weight car. The car that's going to win is going to be the car that's better sorted. The aluminum block is nice though, weight savings is free reliable HP and better braking/handling. The original cars won LeMans twice with a 400HP 289, and weighed around 2,000 lbs.

When you look at a stronger trans to handle 600HP you're also looking at more weight. The Ricardo trans in the new GT is about 300 lbs compared with 140 lbs for a G50, sort of defeats the purpose, as you sacrifice handling/braking capabilities.

 

[Sandy]

Good comments Kalun_D

It was not so much the overall height of the car but the Rears were JACKED up a bit high for my likes. On some cars it seems that a suspension mod is needed, other a twist of the coil over wrench will do the trick. No problem as it seems for the RCR chassis. Just needs to be setup 'proper' /ubbthreads/images/graemlins/smile.gif

The trans for the NLT is about 150lbs (Al, mag less), not sure what the 930 box weights in at but I'll be somewhere close (on the more side) then a G5050. I will keep the weight out as much as possible for sure, but no sacrafice for safety or reliability. That is why I really like the RCR chassis, good balance of things I wanted.

Comments about the Hp -

If a 600hp engine was offered as an option that was be as reliable/efficient/legal as what they used then do you think they would turn it down /ubbthreads/images/graemlins/smile.gif

The tracks that I would end up running are 3mi or less for the most part, not the blazing long 8 or 9 that LeMans has. I don't know much about the rest of the Euro tracks but Willow and Buttonwillow in my area are much shorter. How this related to Hp, not sure but I'll expect that I want an engine with better acceleration and great tires and brakes to support this.

From many comments seen polking around on the web, the real real GT40 cars, they were a handful handleing wise, might be just the crazy speeds they drove at but I'm hopeful that in the last 30+ years that the Tire/Brake/Chassis/Suspension technology has improved in some ways to help support added hp. For the most part I know better that infact a better driver can superceed most all of the above, but hey I'll take it any way I can /ubbthreads/images/graemlins/smile.gif

Sandy

 

[Mike Dozier]

"400 hp is about all that's usable..."

Sorry guys..have to disagree...the car weight is not
what limits the "usable" hp on most GT40 replicas.
It's the Achilles heal known as the transaxle.

I guarantee if there was an economically viable transaxle capable
of HIGH horsepower/torque, you'd see a lot more hp being
built into these cars...especially MK II wannabes.

Now if you define "usable" as
the amount of horsepower you should "rationally" have...
that's another matter. /ubbthreads/images/graemlins/grin.gif

MikeD

 

[Keith]

Hmmmm, an interesting thread. Outright HP or well balanced chassis. For my money, after many years pursuing the "ultimate" lap with various degrees of success utilising high hp US iron vs lightweight "screamers" I have to say that although the jury is still out, I would always go the route of the medium hp, high reliability, well sorted lightweight chassis. "A road race circuit is a course consisting mainly of corners connected by short straights" is what I learnt many years ago, and I've no reason to believe this has changed. There's more time to be gained in the twisty bits than the straights.

 

[Sandy]

[ QUOTE ]

Now if you define "usable" as the amount of horsepower you should "rationally" have... that's another matter. /ubbthreads/images/graemlins/grin.gif
MikeD

[/ QUOTE ]

Well put, I fit this category!

One thing for sure is I don't see high horsepower and a sorted out chassis as being exclusive, that is some of the reason that I went with RCR vs some of the others. The chassis and set up are a huge part of the picture. The 'propulsion' package needs to be well integrated into the picture admittedly.

What's scary is that I thought that I was being pretty conservitive with 600hp given comments that I have had from others with much larger numbers.

Look at what is being targed for new vets, and if you have the cash some of the big Benz's, etc. Pretty crazy.

Lot's of fun in any case...

Sandy

 

[Chris Duncan]

""Look at what is being targeted for new vets, and if you have the cash some of the big Benz's, etc. Pretty crazy"".

Yeah, but that's with way more weight than a kit GT40. Just put mine on the Tanner Racing scales, it's looking like it's going to be 2100 lbs. dry.

Always thought power to weight ratio was a more relevant number than straight HP. So that's 5.25 lbs per HP.

The 2005 vette at 6 liter 400HP, curb weight 3,179 lbs, would have to have 600HP to have the same power to weight ratio.


""Lot's of fun in any case...""

Agree with you there, being able to break the tires loose and get slideways at will is a thrill.

 

[Sandy]

I'm more worried about the 06' vets as claimed 500+ Hp, and if they work as well as the 05, a very fast car (Not enough character for me however). All that while listening to a sound track of Miami Vice and sipping on a soda.

For sure the thrill a big part of it /ubbthreads/images/graemlins/smile.gif I am totally guilty of that!


Something that I'll also comment, and may be due to my not being an experianced driver (Or Speller) is that it is the Raw HP that definitly keeps me in the game.

What I can say from my less then a dozen or so track events is that their is always some very well set up cars, undoudbtly better then mine since they have more $$ and time working on them, but they typically run more docile engines (read less cube), and the folks with great handeling cars like s2000, nsx, boxters, etc. They all do excellent on the corners which are slow for everyone, but get badly spanked by me on the few and straight a ways wher I play catch up and/or pass.

Being somewhat of a newbie on the track will do my best to set up for the straight where I can badly hammer them since the handeling is taken out of the equation a bit.

Again this is just with my limited track time, but when it is all said and done starting a high compression (high to me is 12+ CR) mechanical roller motor is about as good as it gets... Well except for 'driving' the car back on the trailer after a fun day at the track /ubbthreads/images/graemlins/smile.gif

 

[Mike Dozier]

Sandy

My thoughts exactly...I also don't see high HP and a well
sorted chassis as being mutually exclusive. Horsepower
can be a great equalizer in cases where driver skill
or car capabilties are not evenly matched.

If you walked through the pits and asked 100 drivers
how many would like an additional 50 or 100 hp
WITHOUT any significant reduction in reliability, I wonder
how many would turn you down? And I'm not talking about changing a 6000 RPM motor to an 8000 rpm motor.
I'm talking about simply adding cubic inches
and some better flowing heads. That's all it would take to
most "medium hp" V-8 to accomplish.

Money aside....IMHO more torque/hp is always an advantage on a race track,
provided it's reliable and the driver knows how to use it.

MikeD

 

[Ross Nicol]

Well I suppose I am qualified to comment here having raced my car for 2 years on tracks with lots of corners connected to short straights.I am of the opinion that too much power hides handling problems,which is the reason I have retained my 400hp motor and concentrated on the suspension and handling.I have consistently lowered my lap times during this period.I am now at a stage where I have nearly exhausted the driver/confidence/skill/components and am ready for more hp.My car weighs
1060kg or close to 2120lb and I can use full torque out of slow corners (in the dry) with no loss of grip.This is with 300 slick tyres on 11" rims.Now compared to the cobra I race against with 600hp I am 4-5 seconds a lap off his pace (in the dry),however I finished only 2 tenths of a second behind him in 3rd place (in the wet)2 weeks ago after 11 laps.Now I think that says his car doesn't handle as good as mine, I can drive ok and it's the hp that beats me in the dry.I plan to go to 500hp as I believe that power will get me up the front.Time will tell and I will certainly keep you guys informed.
Ross

 

[Sandy]

HP Capability/Useability

Ross -

Some very good points and driving with lower HP and getting good, then stepping up. I know for sure that if I had a lesser capable motor in the mustang I would be a better driver for sure, I know a bunch of SCCA hot shots, and they run stock and hypo BMW's, Vetts, Honda's, Mitsi's, Spec Miata, and most all of them say that it almost dosent matter what you have as long as you get track time _AND_ learn from your bad moves. Setting up the car is important, and that is an area that I do have difficulty with since I do most of the stuff myself. Honestly I have so much fun I get too lazy to start messing with things.

I finally got a in car cam mounted to the roll bar in the mustang, and it has been the most helpful thing I have done. You see some pretty awful things sometimes, but the 'Ripper' (the 65 mustang Fastback) is pretty forgiving. Also give an easy way to get some lap times. Each time out I get better, but the rate of change gets less. So to do better at some point will be to focus back on the car. I have a ways to go for that, but I already know that I hate the way the koni's are set up on the car, so they likely will be attacked first.


My thinking is I should have started with a 700hp motor and put a piece of wood under the gas pedal as a hp limiter /ubbthreads/images/graemlins/smile.gif

I think we should start a new thread for this discussion, I think it is very interesting but some might skip it since the topic is way off now. We should have the thread start with How to go fast in your '40

Sandy

 

Re: HP Capability/Useability

I dont have my GT40 yet, but allow me to chime in on the power/weight theory. The 600hp Cobras that Ross speaks of are just 1 - 2 seconds ahead of my times at my local tracks. The shortest, track, i'm actually quicker. My car has 200 horsepower!! It is road registered, and i simply bolt on a set of 8" slicks to go racing. The car is a Lotus 7 replica, it weighs just 440kg. So it accelerates, brakes, corners like nothing else i've driven. I lose out bigtime down the long straights, but overall, the car is quick. A well handling car will not only be a pleasure to drive, but it will allow you to apply mre power AND use it to it's full.
With my Roaring Forties, i plan to leave the engine (4.6L quad cam Cobra) standard for a while, learn how to drive the car, tune the suspension, THEN get some horsepower.
my 2c worth.

 

[Ron Earp]

Re: HP Capability/Useability

I agree with you Tim. As a new SCCA racer and learning a lot I find that learning to drive a low horsepower car to its limit is teaching me more than driving a more powerful car but having to "watch it" lest I get myself in trouble.

How much power am I talking about? Not much.

The low horsepower car is low, it makes all of 101hp to the wheels, a spec Miata. The "high" horsepower car that can get me in trouble is the TR8 (185 rwhp) and the one that has gotten me in trouble, 260z, at ~170 rwhp. I enjoy driving them all, but I learn more with the Miata than the others, and all of them have good track setup.

All that said though, now that I have learned a lot more there is little difference for me to drive them - now. There was a few months ago but now they are about the same to me, each just requires different habits as they should.

This is one area where a nicely tuned ERFI system could really help out with driver education. You could have programmable RPM limits and reduced timing curves and really take the bite out of a big motor.

Ron

 

[Sandy]

Re: HP Capability/Useability

[ QUOTE ]
...I dont have my GT40 yet, but allow me to chime in on the power/weight theory. The 600hp Cobras that Ross speaks of are just 1 - 2 seconds ahead of my times at my local tracks. The shortest, track, i'm actually quicker. My car has 200 horsepower!! It is road registered, and i simply bolt on a set of 8" slicks to go racing. The car is a Lotus 7 replica, it weighs just 440kg. So it accelerates, brakes, corners like nothing else i've driven. I lose out bigtime down the long straights, but overall, the car is quick. A well handling car will not only be a pleasure to drive, but it will allow you to apply mre power AND use it to it's full.


[/ QUOTE ]

Exactly, but saying your Super 7 has 'only' has 200hp is very misleading /ubbthreads/images/graemlins/smile.gif If you calc that out to a 2200lbs car you are probabally close to 500hp (Also everything works better with th lighter car, CG, traction, Brakes, dx/dt accel that HP only helps with some, the relationship is definitly not linear IMHO). I have run with the one of the local Super 7 clubs here in my are at a local Shelby club run and it is exactly as you said (for the better drivers), they out handle on the tight course, but it is all lost and then some on the 'short' straight on the Smaller (Streets of Willow) course. If the good drivers had some extra juice it would not at all shake out that way, crazy handeling little cars for sure!

The funny thing is that I'm sure that I have said (in one way or ther other) a couple of times that having less power and learning with less powered card is definitly the way to go to become a more consistant driver, so I think we are all in agreement at this point.

For some folks might be more important to be more competitive (or if you are actully racing in sanctioned events, which does make it very important), but for me it is about enjoying the days at the track, having fun, metting some nice people. If I can pass a few folks now and again so much more the better. BTW the Super 7 club was one of the nicer groups that came out, drank wine and bbq'ed with them after day one of the event.

Love the Super 7 in the openning of the 'Prisoner' BTW

Sandy

 

Re: HP Capability/Useability

"Iam not a number, I am a man",,,,,"who is number one?"

Sorry, Couldn't help myself!

 

[Ross Nicol]

Re: HP Capability/Useability

Crazy show eh Faili,My wife and I watched the series again recently, I find it quite dated but still fun.
Sandy I reckon you must be having fun in the Mustang.There is a guy with a 69 coupe that leads the historic field at our race meetings and his oversteering antics coming onto the straight are a real crowd pleaser.I'd love a drive of one.
Ross

 

[Sandy]

Re: HP Capability/Useability

Crazy show for sure! Nice Picture Faili.

Ross I think you must drive the mustangs in oversteer (sliding) as that is the only way to get them around a corner /ubbthreads/images/graemlins/smile.gif It is an easy car to drive and very forgiving which makes it a lot of fun. I'll expect the GT40's to be a bit different to drive, have a few months until I find that out...

 

[Lynn Larsen]

Re: HP Capability/Useability

Sandy,

Learning in a lower powered car is, without a doubt, the way to go. If you want to learn how using the proper line can effect lap speeds, go rent a gokart for a couple of hours and carefully listen to the engine as you try various lines. If you want to learn to handle and use over-steer, rent one at a dirt track. I learned to drive in a 1/4 midget on dirt tracks in northern Califonia and it has served me well for (too) many years.

I am setting up a go-kart for my 13 year old daughter right now to learn to drive in.

Regards,
Lynn

 

[Hershal Byrd]

Re: HP Capability/Useability

Ask any driver if he could have 100HP or lose 100LBS. He will choose to lose the 100LBS.

One comment made by a famous driver after winning in NASCAR in the sixties. He was asked. "What does it take to win a race like this?" His answer was " A size 3 hat and a size 14 shoe." /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif

Hersh /ubbthreads/images/graemlins/smile.gif

 

[Sandy]

Re: HP Capability/Useability

[ QUOTE ]
Ask any driver if he could have 100HP or lose 100LBS. He will choose to lose the 100LBS.
Hersh /ubbthreads/images/graemlins/smile.gif

[/ QUOTE ]

Hell yes!

I remember the old drag race days where 100lbs= .1 sec better quarter mile time. Armed with a torch, a pop rivit gun and some aluminum I destroyed a nice Chevelle SS396. The numbers didn't play out as expected, but it was the easiest way to make it faster since I had not much money for the motor.

The GT40's are tougher to get weight out of since they are already pretty light, easier to add the hp at that point.

I think the easiest way to get some out would be to diet and loose 20lbs /ubbthreads/images/graemlins/grin.gif

I used to drive my 80' International Scout Turbo Diesel (101 hp @2200 RPM or so) on some of the 'trecherous' back roads here in southern California (sarcastic), got lots of time with the sideways driving style which was easy as the truck has almost no power or throttle response. It was the strangest thing, you drove sideways in slow motion.

The Mustang driving is like that but much easier to push the back out due to the hp, need to stay on top of it much more.

Ahh the good old days...

Sandy