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VW rods

SDranger

Well-Known Member
i am building an 1835cc vw motor for my sandrail, and i was thinking of using the scat 4130 I beam rods(5.394") since they are only 150 for a set. Now ive seen diffrent people say that they are only good up to 6000 or 6500 rpm. This is the first bug ive built and i dont know what this motor will rev too. It will have a 69mm stroke 92mm pistons, big heads, a single webber 44 carb, a semi wild cam and 1.25 rockers. ya think those rods are ok? any help would be greatly apprecaited.
 

ntsqd

Well-Known Member
SCAT is a reputable company, I'd call them and ask them what they think. They aren't going to tell you flat out it'll work or it won't, but they can tell what they intended those rods to be used for.

TS

"Teach you all I know and you're still stupid"
-- Howdy Lee
 

vwguy

Well-Known Member
absolutely call up scat and see what they say or you can email them and talk to a person directly
i would also call some vw buggy shops around and ask them what they have used and what they have done with them and what customers found them to work
call rick at ricks sand buggies in norco (909)549-9954 i think he should know

how ironic is it that most people slow down for speed bumps yet almost all of us here im sure pin it
 

SDranger

Well-Known Member
alright, thatnks for the help guys, i'm gonna call scat then and see what they think. Hopefully ill be tearin up the dunes soon :)
 

heavy8

Well-Known Member
unless you build it with king kong valve springs, you dont want to go over 6000-6500rpm. If your going to build it with heavy valve springs (and retainers) , I would save up the money for a counter-weighted crank as well. With a balanced crank that motor will just love to rev. Its like night and day compared with a stock crank.
Good Luck
 

vwguy

Well-Known Member
good point make sure your heads are up to that rpm and everything else as well dont go overkill on the bigger is better thing unless you really do it right

how ironic is it that most people slow down for speed bumps yet almost all of us here im sure pin it
 

DailyPedal

Well-Known Member
Do not go for the rods. VW rods, in a motor as small as yours, are plenty strong, although they must be a "good" set. Call Rimco for a set of HD or race rebuilt rods. Most rod failures in VW motors are due to the builder trying to use a VW case that was too used-up to begin with. VW cases will collapse in the middle, moving the case halves apart, bleeding off oil pressure at the center main. When this happens, the connecting rod on either side of the main journal is starved for oil, seizes the bearing and rod to the crank, and breaks, often through the top of the case. Take the money you saved on the rods and apply it to a good, or preferably new case and purchase a dual carb set. It is very difficult to get a single carb to work good on a playcar motor. Best bang for the buck is dual carbs, (more bottom-end power, more top-end, better throttle response, easier to tune, better linkage available,etc.etc...) choose the right cam to go with your heads and carbs and forget the rockers.
 

ntsqd

Well-Known Member
Hummmm.......
I have a single DGV on a 1955 cc (90.5 x 76) with a mild cam and 8:1. Oh, and Toyota electronic ignition in an 010 distributor. After the usual fine tuning of the jetting it has run great for the last 10 years. There might be a little more top end with dual carbs, but it wasn't built to scream, it built to explore the desert with. Yes, there is a little hestation from the long intake runner. I'll take that and the extra low speed torque over the complexity of dual carbs any day. I've worked on multiple carbed vehicles (Jag XKs, Fiat 8Vs, Abarths, BMWs, Morgans, etc.) and it isn't simple to tune those correctly w/o the right tools, which I refuse to carry into the dezert with me. That's not why I'm there.
As it turned out, I went too small on the cam (Howard's H-1) and later installed 1.25's. My intention was to not use the 1.25's either, but.....
I'll second the good used or new case. I see the rods as an insurance policy. By the time you really trick out a set of stock rods you're usually pretty close to the cost of aftermarket, ready to go rods. That isn't always true, but it is more often than not.

TS

"Teach you all I know and you're still stupid"
-- Howdy Lee
 
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