Poll: On alternate rod

Should Prep 2/Limited Prep engines allowed alt rods

  • Yes

    Votes: 0 0.0%

  • No

    Votes: 0 0.0%
  • Total voters
    0
R

RonInSD

Well-known member
Figured we could leave this up until the Runoffs and bring it up at the tent meeting and them write letters afterwards.

Current Prep Level 2 wording
9.1.5.2.h. Pistons and Connecting Rods
1. Pistons, pins, clips and/or pin retainers and piston rings are
unrestricted. Pistons must be constructed of metal.
2. Stock connecting rods are required, but can be lightened
and balanced.
3. Connecting rod bolts and nuts are unrestricted.


Proposed Prep Level 2 wording: (This matches Prep Level 1 wording)
9.1.5.2.h. Pistons and Connecting Rods
1. Pistons, pins, clips and/or pin retainers and piston rings are
unrestricted. Pistons must be constructed of metal.
2. Alternate ferrous connecting rods of the same crank pin
center to the piston pin center dimension as stock are
permitted.
3. Connecting rod bolts and nuts are unrestricted.
 
Question -

If there are no off-the-shelf aftermarket rods available for an engine, what is the approximate cost and availability of getting something custom? Just as an example, I don't think there are any off-the-shelf rods for the 1.6 Rabbit/Scirocco engine, everything I've seen is the longer rod/bigger big end for the 1.8 (though I'll confess I have not looked hard). I'd assume that, sort of like cranks, you can get "anything" at a price, but custom is usually higher. OTOH in this day of very flexible CAM maybe not hugely higher, after all a rod is a fairly simple think compared to a crank....

To my way of thinking, the cost of the mod has a lot to do with whether it is a good idea to say yes in this sort of admittedly gray zone....
 
I hate blown up engines for poor parts. Nothing good happens thatway.
The issue , not addressed, is where is the line for conversion to good rods.
Can we cut the crank down to a size with common rod size, IE Honda? The Honda rods are way cheap. How far can we cut the crank to fit new rods?
It looks like a pretty easy dominoe into the entire rotating assembly. P1 level

RE the 1.6VW; has nice forged rods, all it needs to run 9000rpm is bolts.

Last week I was for any rod. Now after looking around and listening to the general attitude of everyone. not so much.
Idont want to have to, get a lighter rod to stay near the front, hell we havent even bought real tires yet.
Moma asked last week if we need better tires? The race was great as is, why change anything?

For the few cars that have the rods keeping the engine from hitting the target RPM and power, maybe those cars should be addressed on their own .
It does not appear to be a class wide issue with P2 engine limited to rpm by throttle body/cam/head.
If your car cant run P 2, run the P1.
 
Anyone have to deal with cracked end powdered metal rods? They cost the more than a custom H-beam before you even start doing anything to them. They also can't just be resized like a normal rod when you change the rod bolts. I'm going custom rods in my STU motor, because I want it to hold togeather when I reset the redline to 8500rpm.
 
Just for everyones info, I have bought rods from a guy in the UK with the company name Williams. Like all rods not Carrillo, Pauter or Cunningham, they are Chinese. Even Manley and Crower uses Chinese blanks. They look great and can be had IN ANY SIZE. And at $950 for 12 rods delivered, are pretty damn inexpensive. I would be happy to send anyone photos of the last ones I had made. So complaining about well they don't have them in my size, bunk. Having used Eagle rods in my GT2 car several years back and having no trouble with them, I would not hesitate to use well made Chinese rods. And I have seen Carrillos come apart several times. You just need to cycle parts out after so many hours and make garage art out of the cycled out parts so you don't get tempted to use them in the backup motor.
Chris
 
Al Seim":27gwdq5d said:
Question -

If there are no off-the-shelf aftermarket rods available for an engine, what is the approximate cost and availability of getting something custom? Just as an example, I don't think there are any off-the-shelf rods for the 1.6 Rabbit/Scirocco engine, everything I've seen is the longer rod/bigger big end for the 1.8 (though I'll confess I have not looked hard). I'd assume that, sort of like cranks, you can get "anything" at a price, but custom is usually higher. OTOH in this day of very flexible CAM maybe not hugely higher, after all a rod is a fairly simple think compared to a crank....

To my way of thinking, the cost of the mod has a lot to do with whether it is a good idea to say yes in this sort of admittedly gray zone....
Click to expand...

Al,

Most of the top end rod manufactures like, Pauter, Arrow, and Carrallo are about $900 to $1200 for a 4 cylinder set.

Pauter lists the 1.6 rods for $898 on their web site
http://www.pauter.com/volkswagen.htm

Crower lists the 1.6 rods also for $976 on their web site.
http://www.crower.com/rod-inventory/
B93970B-4 * 1.6 VW 584 410 174 5.827 1.929 0.980 0.787 AS774 HA02
http://www.crower.com/billet-crowerods- ... -5624.html

Again you may be able to get these cheaper from a dealer.

Most of the mid range type rods, like Eagle, SP components, K-1 Technologies etc are right around $600 for a 4 cylinder set. I have seen Eagle "ESP" rod sets as low as $325 but I have heard the included rod bolts are an issue with this lower end rods so you way want to replace them with ARP Bolts which will up the costs.

Most of the mid tier and lower tier rods are made in China so supply may be a little slower and the rod bolts may be an issue. I know some of the mid tier rods include ARP bolts.
 
IMHO, it would make a lot of sense to target the few cars that actually need rods to make RPM. The Toy and the 1275 cars ?? Let these cars make their case and allow them rods.
Add 40# to them and watch the results . If they are a game changer,add more weight to them and leave the rest as is.
 
The longer the discussion goes, the stupider it gets. You get the people who have engines that may have rods that may live not having any sympathy or consideration for the folks who are not having any luck in trying to prep an abuse 40 year old cycled out OEM pieces. I understand and don't care for rules creep as much as anyone as I have never found it very rewarding in the last 30 years of my experience as a preparer and engine builder, but allowing this dimensionally limited concession is just common sense. Remember--nobody is MAKING ANYBODY have non OEM rods !!! The rule as proposed offers NOTHING but dependablity. We limit performance with things that affect the amount of air an engine can consume or compression ratio.

As far as "crack" rods (at least the BMW version)--they are OK UNLESS they need to be resized--which may even be necessary on brand new pieces if you are trying to make clearances as good as they need to be in a race engine.

Folks I know have had mixed results with powdered rods(Chevy)--most bad with higher RPM's.
 
Al
I have Saenz rods on my Level 1 FP VW. Very nice quality, about $600 in 2003. I also have lightened stock rods with good bolts in the other engine that are forged steel and they start out about 100G heavier the big block Chevy rods. Luckily VW guys are blessed with good stock rods.
 
Not stating for or against.

How about, For per spec line replacements they are purchased only from SCCA Enterprises. Only one version for that spec line.

.
 
If you let Enterprises in you will have Carrillo x2 prices. You also must remember this is just an adult game we play. The only poeple getting rich are parts suppliers. The less we spend the more dinners we can take our wives out to. Win-win. It should also be a within 5% of stock weight so we do not get poeple putting in uber light rods that blow up anyway.
Chris
 
zChris":zy17hu7q said:
If you let Enterprises in you will have Carrillo x2 prices. You also must remember this is just an adult game we play. The only poeple getting rich are parts suppliers. The less we spend the more dinners we can take our wives out to. Win-win. It should also be a within 5% of stock weight so we do not get poeple putting in uber light rods that blow up anyway.
Chris
Click to expand...

I don't care what you guys do so won't vote. However i would highly recommend choosing either stock or completely unrestricted and nothing in between. We don't even police gear ratios in prep 2 cars nor do we even have a complete list of throttle body sizes.
I know of three Prep 2 cars that have run extensively with Carrillo rods and who only put the stock ones in for the runoffs. Don't care personally but wonder why new rules would be considered when the existing ones can't even be enforced?
 
I would bet that this represents more votes than letters were sent on most anything put out for MEMBER input. I know that it is sad but true.
 
I'm one of those builders that offer race prepped LP rods, and I'm 100% Ok with alternate connecting rods, it has gotten to the point where it is became more affordable, so why not, the rule was orgianlly written to defray cost. I see some weird comments in this thread though, for example , same weight as stock, forget that, you'll just force people to keep using stock, or have custom rods made, in the more common modern short stroke rods, the weight of the aftermarket rod could very well be heavier, or similar to stock, in long stroke engine aftermarket rods will weigh less than factory, alot less, for example in the MG engine engine about 200 grams less per rod, but is seems like a fair trade since a short stroke engine shoudl rev better to begin with.

Al, Maxspeeding connecting rods for your engine are $560 a set with ARP 2000 rod bolts. Several MGB vintage racers have used these so far, and have no complaints, I tempted at trying a set myself in my next race engine build.

This is one fo the silly LP engine rules that is time to go away, and for sure as more cracked rods are the norm of the modern engine, this makes eve more sense, Caterham racers having to deal with this is utter madness. Maybe next will be the reduced valve stem diameter under the guide, I told Kevin D. at the time it would impossible to police, it would cost racers more money, and only made a few CFM flow increase on the flowbench at middle openings, but all that feel on deaf ears.
 
I voted no. I probably have one of the worst engines for both rods and cranks with the 1500 spitfire. But we limit RPM and have worked to make the power within the power we have. I limit to 7000rpm, and that allows for about a 500 rpm on missed shift or f up.

I agree if you allow rods, you have to allow cranks.
 
Should we change the name from limited prep to limited performance and just allow almost anything?? Do we just want aftermarket rods, or more stuff??

It is currently called limited prep, a limited prep motor might only be good for 7,000 RPM. If you want more RPM, there is full prep. With the limited prep performance limits, stock head, no porting and limited cam and compression, is there much to be gained by going over 7,000 RPM??

My car has tiny brakes, I can work with what I have, or I can go to GTL and use any brakes. But if I go to GTL I would have to start all over building the car to take advantage of the GTL options.
Part of SCCA racing is working within the rules that we have.

A broken motor does not limit cost, regardless of how or why it broke. So maybe something should be changed, but need to look at the entire concept of limited prep.

Limited prep should allow more entry level or smaller budget prod cars, and diffrent options for all of us. But a broken motor is not good for any budget.

I think the idea of limited prep was partly to encourage more people to enter Prod classes, but if the rules are making us break engines, that won't encourage more to join us.

Custom rods are not cheap but not crazy expensive either, and many engines have aftermarket rods available. If I can lighten OEM rods, then why limit the min wieght of aftermarket rods?

Why not just have the rule state; modified OEM rods or any steel rods (no aluminum or Ti)????
 
Stupid?? really..
These are opinions of your fellow racers.
I know that if rods are allowed , most new builds will use them. Why?
Turn the crank down to fit new lighter rods, well undersize. reduce the bearing area = go faster.
Now we have crank issues for the 2-3hp that may be the result of the new rod rule.
As an engine builder you have to sell the best engine, so rods are required and the domino engineering that goes with them..

If one or two cars have issues , let them have rods, on stock crank sizes+-025
Will the affected cars go faster, more often?? , yes. Will it affect my car?, maybe.
It is a lot easier to add weight to a car that we made errors on, than refigure the whole class now that we all can rev to intake limits..
Test the water, dont dive over the edge. IMHO.
 
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