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Wed Oct 06, 2021 9:09 pm

Hi Samba Users,

Question for the drag racers! I put some 26x6 15inch M&H slicks and front runners on my bug for drag use only, just wanted to know what pressures you run front and rear? Raced it last night with 18PSI in the rears and it was a little skatey through 1st and 2nd.

Plug for CB Performance.
Running a 2054 all CB parts, panchito heads 40x35, CB 2288 cam, 10.5:1 compression, IDA's 37mm vent, close gears in a stock body bug no interior.
PB last night of 12.6 @ 104mph. Was great fun for a simple build. Great parts.

Cheers for your help guys.

Thu Oct 07, 2021 4:03 am

I have 3 sets of M&H racemaster slicks and all handle different :shock:
The D.O.T.'s are the trickiest, usashully on the end of the strip if I have low pressure the bug wants to 'hula' skirt' (15psi) sounds like you were just spinning in 1st & 2nd :lol: I try to keep the pressure around 18 psi too ,better to spin the tires then break trans gears etc. :lol:

Thu Oct 07, 2021 4:17 am

A little different, but I ran the M&H Racemaster DOT tires on my 64 Nova…same size (215/65R15). I would run 25psi, my Nova weighed 2700lbs, but most of that was in the front.

I would bump up the pressure under you begin to slip too much.

Thu Oct 07, 2021 5:53 am

While I would consider how well the track was prepped (I've raced a full-bodied turbo'd Beetle and Ghia on the M&Hs at ~18 psi without traction issues), many VW racers complain that the M&H front runners make their car feel squirrelly. I've driven some sloppy crap, so I've never been unsettled by the front runners, but perhaps this might contribute to why your car feels "skatey"?

Thu Oct 07, 2021 6:17 am

First, they are NOT radial tires.
they are bias-ply.
As such, they will always feel floaty.

For me:
The 6" M+H slick, I could only run it down to 16psi before they were scary to run.
Even at 18psi, they would dance around some. You just gotta get used to it..

For the DOT's. I couldn't run them less than 18psi before the same would happen.
Even at 26psi on the street, they were ill handling.
Not really meant for street use.

There is just no sidewall to these tires.
Great for 60' times... Just not great handling.

The switch to 8" wide M+H's changed the game for me.
I can run them at 16psi and they don't' wander around at all.

It's really a different tire. Sidewall is much thicker on the 8" slicks.
Zero traction issue too.

Thu Oct 07, 2021 7:15 am

Thanks guys for the input. It runs nice and straight at the end of the track, and yes the track was not fully prepped. We have Wednesday night racing here and it has started a month or so before the official drag season. definitely had wheel spin, so maybe when the surface is better it won't move around so much.
Appreciate all the help.

What pressure do you guys put in fronts?

Thu Oct 07, 2021 8:54 am

I have m,h 215 racemaster dot's on my 67, anything over 11 psi and tires will spin, at 11 they still bark 1,2and 3.

Thu Oct 07, 2021 9:20 am

I run the M&H 215/65 DOT usually at 16 to 17 psi and spin a revolution or two out of the hole to save the transaxle. 60 foot times are mid to high 1.6s. Anything over 18psi and it blows the tires off. At 15 psi it aims for the sky. 2000lb with driver 67 street bug, 2276cc N/A making about 215 hp at the flywheel, 24mm SAW torsion, Geers spring plate retainers and QA1 single adjustable shocks set real soft.

Thu Oct 07, 2021 10:30 am

stealth67vw wrote: I run the M&H 215/65 DOT usually at 16 to 17 psi and spin a revolution or two out of the hole to save the transaxle. 60 foot times are mid to high 1.6s. Anything over 18psi and it blows the tires off. At 15 psi it aims for the sky. 2000lb with driver 67 street bug, 2276cc N/A making about 215 hp at the flywheel, 24mm SAW torsion, Geers spring plate retainers and QA1 single adjustable shocks set real soft.

Very nice...
You got that one hooking up good.
1.6's 60's are just right.
I think that was the limit for me too running them.

I use to race an all-motor/DOT tire class at import events.
So, I had a set of rims and DOT tires in the trailer I would swap out for these events.
I would clean house over the FWD Honda's all day long.

Thu Oct 07, 2021 1:17 pm

Wish I could get mine to hook at 17, top end decell would be a bunch nicer. Running between 1.55 and 1.62 60's.

Thu Oct 07, 2021 7:52 pm

deadkombi wrote: Hi Samba Users,

Question for the drag racers! I put some 26x6 15inch M&H slicks and front runners on my bug for drag use only, just wanted to know what pressures you run front and rear? Raced it last night with 18PSI in the rears and it was a little skatey through 1st and 2nd.

Plug for CB Performance.
Running a 2054 all CB parts, panchito heads 40x35, CB 2288 cam, 10.5:1 compression, IDA's 37mm vent, close gears in a stock body bug no interior.
PB last night of 12.6 @ 104mph. Was great fun for a simple build. Great parts.

Cheers for your help guys.

Hey long time no hear! Thats gotta be a record for 40.35 heads! 12.6 is really moving! And it shows what that you did it all right. Nice job!!

Thu Oct 07, 2021 11:01 pm

I’ve been running M&H dot 215 /65 since there conception in 2003 .there is no magic psi number as there is way to many variables.
The number 1 thing is always run the pressure that allows the car to be stable and safe at your mph crossing the stripe , all the rest is up to chassis and suspension setup and clutch tuning during launch.
I run 20 psi up frt and 16 psi at the rear on John’s tires , I will tell you I have pushed those tires to there limits and I still think there is more in them .my 60’ are consistent low 1.4 ‘s and mph is almost 145 with et in the 9.8’s .
Vehicle with driver is 2000 lbs . Just FYI the dot tires are the same compound as the slicks just With a slightly stiffer sidewall / extra ply to get the DOT rating . Which is great for heavy cars or better yet turbo cars, I would not go lower than 14 psi . I ran that pressure to 11s at around 120 -125 mph . And any lower the car felt unsafe , doable but unsafe.

Here we go ,always fun to watch a quick video .
16 psi and thinking I now have things dialed in at launch

https://youtu.be/drmB_UcNJMs

Fri Oct 08, 2021 6:16 am

That's a 'Dame nice pass' :wink:

Fri Oct 08, 2021 6:24 am

mcmscott wrote: Wish I could get mine to hook at 17, top end decell would be a bunch nicer. Running between 1.55 and 1.62 60's. When I ran 28mm bars, I couldn't hook at 14-15 pounds. Doug Berg and Wink told me the rear was too stiff so I dropped to 24mm bars and it hooked much better at higher tire pressure.

Fri Oct 08, 2021 11:13 am

Here is a big tip.
Do not freak out on 60 foot times . It’s just a number and yes it means getting up and going I get it . BUT
Years ago in my nitrous days car ran real fast and nice and easy in the mid to low elevens but I was so worried about my 60 foot times .
Finally figured it out GEARing .
My first gear was if I remember like a 4.11 with a 3.88 ring .
So what was happening is car got up and left nice but I just needed to shift to 2nd before the 60 foot .
End of worries about 60 foot times .
Most of those videos of my car on you tube are
When I was working on clutch management.
If you take the time and watch them you will see
The launching issues .
If you have questions after let me know

Sun Oct 10, 2021 12:27 am

Thanks for the advice and help.

I was surprised with the time, and I'm sure it got more in it. Last season I ran it over 100 passes, with the same engine but had street tyres and 1.25 rockers. I've put some 1.4's in it and upped the compression a bit and obviously changed the tyres. I did notice it has dropped the rpm by about 300, to 6800 over the line which feels better. It's great fun anyway trying to shave off 1/100's of a second even. Speeds gone up slightly too, the 12.6 was 104mph.

Cheers guys, all the best.

Mon Oct 11, 2021 12:00 pm

man.. 12's VW's are fun to drive..

Can put down almost anything in a street battle..

Front end lifts hard under acceleration. So hard that the steering geometry goes to shit and you have to crank the wheel to compensate.

Gets passengers attention real fast. I love it when the reach for the grab-handle.