Choosing Right Manufacturer - Long Question

[Sandy]

It's finally time to cash in those stock options /ubbthreads/images/graemlins/wink.gif

I need some help from some folks as well as any manufactures that are willing to comment (PM ok as well). I'll set this up with what I am looking for and what I want in the car.

Gear box RBT-ZF minimum (easy to get for me, RBT local), prefer Sequential Hewland NLT (questions of fit and engine adapters for SBF). Many have options for ZF, none for Hewland, I'm pretty sure that the G50 boxes would not be a good choice due to the HP.

Motor (shhh...I have this stuff hidden from my wife) RDI SBF aluminum block like the current one in my 65 FB is making about 570hp, likely next will creep to about 600hp out of a 331 carbed. Bundle O' Snakes for exhause of course. Hefty radiator will be required as well...

Brakes, large SL6's, prefer Wilwood again, local, common.

Rim/Tire capabaility, this is the big area of question for me, I want to have a chassis that is capable of supporting large tires and working well. Large is subjective as I have seen here on the list, 255-275's are not large! 335's are getting OK sized for rears. Probabally stick with 17's due to ability for large rotors and tire size choices. Yes, Gulf flares. Could go either way on pin drive, if I can ditch it for larger tires then it's gone.

Chassis, probabaly mono, but not 100% sure. I have a Herb Adams VSE Cobra that is aluminum mono (unfinished) but I like the initial looks for RCR's but lots of questions for Fran. I am looking for more track time then street time so a better designed suspension and chassis is very important. I would say I will trade any sort of street driveability for better track ability.

Body, GULF treatment, MK1 which seems to be the most popular and the best looking! 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.

Safe-tee, Fuel Cell mandatory (RCR question). Possible Roll Cage if not integrated already.

My friend spanked me in his preped EVO 7 last week, time to turn the tables, well not even sure if a good GT40 could hammer the EVO, it's crazy good handeling and fast. But I have diverged...

So who has comments on track driven cars, and can comment on the handling aspects, stability and what your manufacturer might be.

I'll likely look for someting more assembled (roller-) but not 100% sure, local or US presence better too.

Some of the companies I have been looking at and comments -

RCR40 - Like the chassis, need to see the finished one, questions about tire size, handeling, transaxle. Also would require more work to get rolling as roller- is not an option.

CAV - Mono, I have liked them for a long time, seem most likely if feed back on track is good. I need the race version they offer ;-)

Baily Edwards - Not sure what the chassis looks like, but very nice GULF version on the site, seems to be touting best of track cars, but otherwise very lacking on web available information.

Roaring 40's - Looks pretty good, fellow in texas building one I think with Hewland LG, and similar (but larger) engine config. Not sure about handling, but looks ok as well as easy to get info.

MDA - Looks interesting, less then informative web site, some interesting info.

ERA - Mono, Looks good, but looks like they nickle and dime you for every thing on the car. Suspension is in question in my mind for some reason, but not really sure why (MG steering rack, odd mix) Owner Comments? They do have a very complete set of accurate parts, but that is not so important to me. ZF easily supported.

Others???

Well, now that that's done please any comments, and this is NOT in any way intended to start a my 40 is better then yours thread, I just need some feed back on what owners (and as I said before manufacturers) can say about them. PM is ok.

Thanks, this is a great site!

Sandy

 

[Mitch D]

Tough Choice - but it\'s yours to make

Sandy, I fear you'll crash and burn with a question like this. There is no right answer. This is like asking how to choose the right woman, the best NBA basketball team, the best beer, etc.

Mitch D

PS - actually - choosing the best beer is easy - it's whichever one is FREE and WITHIN REACH

 

[Ian K]

Re: Tough Choice - but it\'s yours to make

Sandy -

Some points to ponder and other answers:

Porsche G50 transaxles can handle up to 700 HP if modded. And
still probably run less than RBT/ZF and Hewland. Also, look
into Quaife.

Most of the replicas that you have seen with the rear slightly
raised are due to the fact they probably have Audi transaxles
(or possibly Renaults that haven't been lowered a bit).
G50s and Quaifes sit correctly because they can be flipped.
ZFs are just slim to begin with.

Other than those points, the rest of your needs can probably
be handled by all of the companies mentioned.

Ian

 

[Sandy]

Re: Tough Choice - but it\'s yours to make

Yes, but don't you always ask a friend for the inside scoop before you waste any time with a particular gal /ubbthreads/images/graemlins/smile.gif

Most of my questions are really looking for people that track their 40's and what results they might have had.

Any by the way, since I am from LA I would only go with the Lakers while they were a winning team, then abandon them when they aren't /ubbthreads/images/graemlins/smile.gif

Sandy

 

[Sandy]

Re: Tough Choice - but it\'s yours to make

Ian -

Why should the transaxle affect the ride height? Is it to fix bad half shaft angles, and that seems bad altogether. I have looked at the Quaife but don't see anyone running them in 40's just lots of talk about them. The NLT Hewland is my first choice, since I can get it sequential and I'm happy to have the straight cut gears and dogs, the porsche boxes needs a good amount of work so I don't pump the gears out of one, and would be a second choice to an RBT-ZF, and as I said they are close to LA and probabally the most 'compatible'. The porsche boxes are actually plentyfull here in LA, go figure, but they are suspect at this point, and better to start with something HD.

The trans is the biggest variable cost as it could range from 9k-25k or more. That is one of the important questions, which guys are running what trans with a BIG tire and a decent motor.

Keeping this in mind I never want to hear myself say, "Hey take it easy so you don't blow my trans"

"Damn, almost had it" - Mr. Guts, Cannonball Run

 

[Ian K]

Re: Tough Choice - but it\'s yours to make

Sandy,

It has to do with how the Audi (and Renault) boxes fit. They
cannot be flipped, so the CV/U joints fall below the transaxle
centerline. At that point, to lower the boxes enough would
cause serious interference with the chassis as well as
ground clearance in general. The Renault can be lowered a
little (Howard's Betty is an example), but the Audi cannot.
The ZF has a low enough profile flipped or not, and the
G50 and Quaife can be flipped so that the CV/U joints are
above the centerline, allowing them to sit very low in the
chassis, giving you more play with ride height and clearance.

Check out some of the build pix, or the RF website. Look at
pix with the rear open. You'll see what I mean. A search on
this forum should turn up many discussiosn regarding this.

As far as a Quaife box goes, IIRC, Roy Smart in the UK now
uses one. Paul Thompson could probably better answer this.
He posted pix before, but I cannot locate them.

There are plenty of guys running modded G50/5x boxes - they
are plretty bullet proof. The mods needed would still
keep you under $15K.

Ian

 

[Ron Earp]

Re: Tough Choice - but it\'s yours to make

On the RF/CAV with Audis it affects engine height in the chassis but not really ride height. And, it isn't a huge difference, but it is there. There are tricks with the RF to get the box down low in the chassis - I had mine down very low by using Hershals tricks with some fabricated solid mounts - got the engine level and the tranny lower down. For serious track work I'd do one of the boxes mentioned. I'm going to try and Audi and track it hard, but don't expect much. If it lasts, great, I'll be pleasantly suprised, but I'm not expecting a lot.

 

[Brett James-McCall]

Re: Tough Choice - but it\'s yours to make

Sandy,
For trans questions, speak to Paul Thompsonnn on his experience in Roy's car with the Derek Bell upgradee for the Renault. Also, Stuart B (Birchall) is curently working with Quaife on a 016 upgrade that will prve interesting IMO. They should all work out cheaper than an RBT and maybe weigh less.

BTW if this doooesn't make sense appologgiess as I have just sharedd 5 bittles of wime with a friend and havee workl in 7 hoursasa. Bye. I love you guys

 

[Sandy]

Trannies and such

I'm still a bit hammerd and I'v been at work for a couple of days since the news of the company's buy out /ubbthreads/images/graemlins/smile.gif. I'll likely not use a renualt box, but the Quaife is interesting (uses the texel torson diff which is good), and I think the MK3 has straight gears and dogs, which again is very much my flavour of trans. I know they have one that is a porsche replacement, but not sure about the MK2/MK3 boxes as I think they have no prices on the USA Site. The RBT-ZF sounds better and better, easiest to fit, supported by most chassis, a short drive to RBT, but I do hate the position of 1st as in the pantera (I drag raced a freinds stock one a few times, and I can tell you it is not set up for a speed shift on 1 to 2!). But hey I'm older and more docile on the cars these days...

Thanks for the tips, and pound a pint for me!

Sandy

 

[Craig White]

Re: Trannies and such

Have numerous GT40's here running stroker 302w(347ci) and the G50 boxes seem to be able to handle the power fine, even for a fair amount of race use. Some of G50 gearboxes would have had years of use/abuse.

I have DRB GT40(GT40 Australia), they all run G50 boxes and you have a choice of U joints or CV joints. See if there is one local to you to have a look at, would be worth adding to the list of possibles.

As for track use and DRB, best person to talk to would be Flatchat on this forum. Quite a few DRB GT40's have seen a lot of track use, but I doubt if there are many GT40's around that have seem more track use that Flatchat's old baby.

 

[Richard Timte]

Re: Trannies and such

Sandy,

The ZF has helical cut gears and syncros not straight cut gears or dog engagment. I recevied this email from one of the members here that races his Pantera:

Hi Richard,
I saw your string of emails on GT40.com and just want to contact you regarding
your research into "straight cut gear" transaxles. I have built a Pantera for
road racing with an engine very similar to yours (specs attached for reference)
and can assure you that the ZF "helical cut gear" WILL NOT withstand 700hp/600lb
engine output.

I have a fully race prepped ZF-2 transaxle and have grenaded it several times,
including sheering the teeth off 4th gear 'twice' while rolling the throttle
exiting a turn (picture attached).

I am currently having it rebuilt again at RBT and are investigating custom
straight cut gears for 3rd, 4th, and 5th. Anyway, I wanted to ask you what are
your plans are for the transaxle in your GT40 application, as it may influence
what I am doing?

Thanks,
Gregg

Just thought you would like this info to help with you decision.

 

[Hershal Byrd]

Re: Trannies and such

Here's a comparison of a RF to the real deal. I personally can't see that much difference in the ride hieghts. You can acheive just about any ride hieght you want by using lower profile tires or higher if that's what is needed . Shocks can be changed or adjusted along with spring tension. A whole bunch of adjustability can be had.
I've said it many times...The 016 IS a great box. It does a wonderful job for the intended use. Ther are just too many in use without major complaint to discard it. With minimal cost the fifth gear can be changed out for a better cruising gear. It's not going to take 3500 RPM clutch dumps at the drag strip but on the race track it's a great trans. These cars weigh very little compared to what the 016 came in originally. Regardless of engine size more than 500HP in this car is usesless IMHO. It just is not needed to get around most tracks we as Amateurs use. Unless you are a pro driver and race on a regular basis then excess HP is nothing more than a number to put on your show card.
Jerry's car has a 331 and it's scary fast. Chuck's 306 ci Gulf GT is scary fast. I think if you ask them they will tell you more HP won't make that much difference in the lap times. You need a huge track to use a lot of horsepower.
Maybe Jerry can shed more light on the 016 ratios for most tracks. His Driver Mike would be able to tell us how it does as well. If anyone else has experience racing with these boxes please chime in and tell us what the pros and cons are. Personally I like the 016 alot on short to medium tracks. Never been on a long track.

Hersh /ubbthreads/images/graemlins/smile.gif

 

[Sandy]

Re: Trannies and such

Richard, thanks for the photo. You are the one with the nice Hewland, that is my choice for an NLT sequential, just not seen any in a 40. I have the RDI block in my mustang and while not quite as big as the 351, getting up in power and really don't want to see a splatter of gear like the one from the ZF. My question is if the Hewland is out of reach ZF or G50? I guess the Quaife is still an option and will have to do a bit of follow up on that. Are you working on a RF40's chassis, I can't remember. Do you have a connection for the Hewlands'

Thanks

Sandy

 

[Sandy]

Re: Trannies and such

[ QUOTE ]
Regardless of engine size more than 500HP in this car is usesless IMHO

[/ QUOTE ]

I very glad you have the IMHO /ubbthreads/images/graemlins/smile.gif, My 65 Mustang with the 331 SBF was dynoed at 568@7k with about 460lbs torque, Power looks like it flattens at about 7.5k somewhere (just a guess) 575hp. I can say that even on the short track at Willow springs (check out the Streets of Willow for the course) you can use all you have and then some in the 2 straights, then apply LARGE amounts of non-ford brakes, and this is in a 65 Mustang that I can say handles no where as well as the 40's or anything modern, on the big track at willow it's a bit different, the car is too fast for the long straight just due to the poor aero design (Scary watching the rear of the hood start to lift the hinges...) but fun to drive never the less! I am an ok driver, so most of my improvement would be had with driving skills at this point but I still want the juice /ubbthreads/images/graemlins/smile.gif

On the tire subject, in looking around some of the problem I have with the rear ride hight might actually just be the fact the cars are running modern tires, which I guess is just lowering the car a bit, I think one of the older threads in the suspension section had a set of post with pics that show it done up nice, nothing some suspension tuning as it seems.

And don't ask what the all aluminum Big Block Chevy makes that I have for the VSE aluminum chassis cobra (now call the never ending project...). Hmm, I think RCR40 can take a big block chevy (A bad idea, and I'm kidding!)

By the way, to all, thanks for the input and to those that PM'd as well.

Sandy

 

[Hershal Byrd]

Re: Trannies and such

Good Luck Sandy,
It sounds like you know what you need and can handle it.
Maybe I'll get a chance to see you in that Mustang on the track someday. /ubbthreads/images/graemlins/grin.gif

Hersh /ubbthreads/images/graemlins/smile.gif

 

[Sandy]

Re: Trannies and such

By the way for the tire fitment I'm talking about check out the DRB site www.gt40australia.com in the gallery almost every car sits right! Hershal much tighter then all of the above photos.

And thanks Lee for the tip to check them out, very nice and the DRB looks more aligned to what I want then some of the others. I guess I'll have to bug Chris as it seems that he was a frequent track user of his.

Sandy

 

[Mike Dozier]

Re: Trannies and such

Sandy

Most of those who track their GT40 replicas
are in the UK (nearly all GTD based), and Australia
(DRB/RF based). By comparison there are darned few racing
GT40 replicas in the US. Hopefully that will change over the next few years as more cars are completed and more
opportunities arise for replicas to race in the US.
Good luck with your project.

MikeD

 

[Richard Timte]

Sandy,

Send you a PM with contact info on a couple of sources for LG500/LG600's.

 

[Sandy]

Thanks!

 

[Tim Kay]

Sandy,

If your idea of fun is driving a sequential and cost isn't a big concern for you then consider the Fortin trans. Sequential dog gear 5 & 6 speed. I was close to pulling the trigger on one but after heavy consideration I opted for a modified G50. In addition, length on the Fortin may be an issue and take some modification.

I have a 4 speed sequential (dog gear of course) Fortin trans in my recreation off-road car. Sweeeeet, very sweet. Louuuuud, very loud. Straight cut gears will give a headache to anyone listening within a city block except the driver /ubbthreads/images/graemlins/smirk.gif He (I!) paid too much to let a little 'tranny whine' bother him /ubbthreads/images/graemlins/smile.gif (Albeit, noise may be a bit louder in an open off-road car and no helmet)

Straight cut gears, unlike engine noise, have a distinct fevered pitch that rise above just about any other noise. You may already be aware of this but for others considering, it may be an issue. Don't get me wrong, I wouldn't trade for anything. The thrill of shifting dog gears just adds more to the already exhilarating driving experience and I for one love it. But would I do it in a track car? - maybe. In a street car? - no way.

As far as the ride height goes, from what I have seen, a common tire used is the BF Goodrich which have over 26" diameter (closer to 27" I believe) and I think that contributes to the look you are describing. The Hoosiers allow me to lower my ride height where I like it. (and this is with a Renault)

(Ron, your Google spell check came in handy on this one, thanks /ubbthreads/images/graemlins/cool.gif)