KA stock rod HP limit reached :)

Post by **IvanAtSPRacing** » Wed Feb 09, 2005 6:47 pm

After making 502 WHP with the twins S13 R&D car we decided to get some video of it on the street. We had been running 25.5 psi on the dyno and the clutch was slipping in 4th gear so we decided to turn the boost down. I turned the MBC out 1.5 turns and headed out for the street.

1st and 2nd gear were usless and third spun pretty bad also. After about half a dozen blasts down the road paying attention to keeping the car straight, I noticed the boost gauge was getting pinned (30+ psi).... oooppppsssssssss. I couldnt believe that a 25 degree drop in tempature could throw the MBC that far off. I turned the boost down to a respecable 24 psi and had some fun.

Since the little jaunt on the street, I noticed that when ever the car was left outside for a period of time and it got really cold, the motor had a tick to it, but when the car was inside the shop all night, when we started it in the morning, no tick. Various ideas were tossed out reguarding what the noise might be. Valve lash might be off, forged piston slap, rod knock were all brought up, but to me it just sounded different.

I needed to change the clutch on the car, I need to upgrade valve springs and retainers for cams I am planning on installing, and I really wanted to see how the motor was holding up, so I decided on pulling the motor and doing a full dissassemble.

We yanked the motor yesterday and dissassembled it today. Prior to pulling the head, we checked valve shim and found it to be in spec. Pulled the head off and pistons looked perfect. Pulled the pan and found everything in order. I was a little stumped as to where the noise might be coming from. Then I noticed it. With No.2 and 3 pistons at TDC I could see that No.3 piston sat just a bit lower then No.2. About 1/16" I flipped the motor over and looked closly at the rod and I could see that it was now slightly S shaped.

As you can see by the straight lines drawn on the pictures, the rods are bent both ways which basically shortened the length. I believe that the piston was slapping while the motor was cold due to misalignment.

The rods are stock KA S13s that have been shotpeened and have upgraded ARP rod bolts. I believe the HP level we were at (at 30+ psi) was in the neighborhood of 550 whp.

Just another informative post from your friends at PhatKA-T

Post by **TrunkMonkey** » Wed Feb 09, 2005 6:55 pm

do it again!

-demetrius

Post by **nissanfanatic** » Wed Feb 09, 2005 6:59 pm

Thanks for the info! Good find.

Post by **IvanAtSPRacing** » Wed Feb 09, 2005 7:00 pm

I think we will pass on that

I really did want to find the limits of the factory rods. I am gald that I didnt toss a rod out the side of the motor. I think it worked out well this way.

Crower rods going in soon.

New clutch is at the shop.

New ignition system is at the shop.

Waiting on valve springs and retainers.

Boost cams are at the shop.

Racing intake manifold waiting to go on.

HUGE HP numbers coming soon.

Post by **H.D.HUMPERDINK** » Wed Feb 09, 2005 7:00 pm

Wow. Thats all I have to say. Wow!

Post by **WDRacing** » Wed Feb 09, 2005 7:06 pm

Ya know there are easier ways to lower the compression Ivan...

I haven't seen to many rods bend like that. Most of the time they are simply snapped. Congrats on the accomplishment.

Post by **toki** » Wed Feb 09, 2005 7:20 pm

excellent information.

I still giggle when I think about a year ago when I told people I was going to turbo my KA and all I got was like "man I hear the rods are only good for like 7psi" or that the truck motor could never make any power.

Post by **TheOne** » Wed Feb 09, 2005 7:20 pm

the rods could probably hold that much, it must've been the hot/cold that could've weakened it.but nice! at least i know it'll do 20 psi on stock rods.so ya shottin out for how strong can the ka motor be? or the heads?

Post by **IvanAtSPRacing** » Wed Feb 09, 2005 7:30 pm

WDRacing wrote:Ya know there are easier ways to lower the compression Ivan...

I haven't seen to many rods bend like that. Most of the time they are simply snapped. Congrats on the accomplishment.

But WD..... Its MUCH MORE FUN this way

I thought the rod was sweet looking... Kind of like a spring.

Thanx for the compliment. Hurry up and get out of the AF and lets open a KA shop

Post by **fiznat** » Wed Feb 09, 2005 7:35 pm

Smooth work Ivan, way to break another customer's car! haha

Hey speaking of "The Twins," who the hell are they and why arent they on NICO?

Post by **klattr1** » Wed Feb 09, 2005 7:48 pm

IvanAtSPRacing wrote:
New clutch is at the shop.

what clutch did you decide to go with?

Post by **IvanAtSPRacing** » Wed Feb 09, 2005 8:04 pm

fiznat wrote:Smooth work Ivan, way to break another customer's car! haha

Hey speaking of "The Twins," who the hell are they and why arent they on NICO?

The twins are Heath and Keith Henderson. Long time customers of ours. They wanted to do an SR swap and came in to talk to me about it and after a long talk with them, the agreed to leave their car with me to R&D a turbo kit for the KA. These guys are the best. We worked out a great deal for them on parts and install in exchange for the use of their car for months and months of down time. This winter the car came back for more upgradeds and R&D.

They do make it to some of the forums at times, but I think they are more into just enjoying the car rather then hanging out on the internet

Post by **IvanAtSPRacing** » Wed Feb 09, 2005 8:06 pm

I talked to my good buddies at RPS and they sent me a 6 puck dampened disk and pressure plate that they say will hold the power and still be good on the street.

Post by **Nismo_Freak** » Wed Feb 09, 2005 8:22 pm

IvanAtSPRacing wrote:I talked to my good buddies at RPS and they sent me a 6 puck dampened disk and pressure plate that they say will hold the power and still be good on the street.

You might want to watch the wear on the thrust bearings with that clutch.

I know because they wanted to sell me the same thing

Post by **fiznat** » Wed Feb 09, 2005 8:43 pm

^^ I actually have the same clutch.

Watcha talkin about Nismo Freak?

IvanAtSPRacing wrote:They do make it to some of the forums at times, but I think they are more into just enjoying the car rather then hanging out on the internet

Hey, the two arent mutually exclusive at all! I hang out on the internet AND I enjoy my car. ...Well, as much as I can enjoy it at 0 RPM, 0 MPH

Hey Ivan, if you could get a general cost for replacing the rods that would be pretty cool. ...Something that includes the price of the rods, all machine and balance work, bearings, etc. Nothing on the level of advertising (I dont think you even do machine work do ya?), just for reference for those of us who might sometime down the road want to *cough* upgrade their rods.

Post by **Jeff240sx** » Wed Feb 09, 2005 9:01 pm

fiznat wrote:Hey Ivan, if you could get a general cost for replacing the rods that would be pretty cool. ...Something that includes the price of the rods, all machine and balance work, bearings, etc. Nothing on the level of advertising (I dont think you even do machine work do ya?), just for reference for those of us who might sometime down the road want to *cough* upgrade their rods.

Rods are ~$400-600, depending on brand. You can't do machine or balance work without the whole rotating assembly, and anyone who says they'll do it for you is just out to BF you. Bearings vary widely on cost, from Discount Autoparts to Nissan to Nismo to Clevite.Anyway, I don't really see anything Ivan would be able to place a pricetag on. It's all so dependant on your setup.-Jeff

Post by **Dattebayo** » Wed Feb 09, 2005 10:12 pm

Wait lets get the whole information, cause i know that S13 rods are supposed to be different from S14 rods. Please speak up if i am wrong... The info came to me a long time ago on the OLD OLD forum back in 2000.

Post by **Jeff240sx** » Wed Feb 09, 2005 10:37 pm

2BN_S13 wrote:Wait lets get the whole information, cause i know that S13 rods are supposed to be different from S14 rods. Please speak up if i am wrong... The info came to me a long time ago on the OLD OLD forum back in 2000.

.

No. Not AFAIK. There was talk about the pistons bieng different, but that was never substantiated (different sources say different things). However, rods.. never changed to my knowledge.-Jeff

Post by **fiznat** » Thu Feb 10, 2005 5:09 am

The car Ivan is talking about in this thread is very similar to my car, so I thought any comparison he made as far as costs would give me a fairly accurate generalization for my projected costs if I decided to do it at some point. I know you need to have the entire rotating assembly out for balancing and bearing matching etc-- I would pull all of those parts out myself, just like I expect Ivan would in order to keep costs down... I also know how much rods and bearings cost-- the only real variable is how much the machine shop charges to match new bearings, re-balance the assembly, fit the rods if necessary, etc.

Post by **Structure240sx** » Thu Feb 10, 2005 6:49 am

that rod looked cool, i think you made Fiz a little nervous

Post by **GEO** » Thu Feb 10, 2005 8:17 am

Ivan, vids please?

Post by **fiznat** » Thu Feb 10, 2005 9:02 am

Structure240sx wrote:that rod looked cool, i think you made Fiz a little nervous

Heh you're right, he did. I mean I dont plan on ever pushing that much pressure, but dammit I dont like to hear that my rods are actually somewhat close to their breaking points at this power level-- even with a 7000rpm rev limit (which is what Ivan had...). I'm not about to pull the motor NOW, but arrhg I wanna at least keep it in the back of my mind how much it'd cost to do it really right...

GEO wrote:Ivan, vids please?

The 502 whp run is on his website phatka-t.com ...Well it was anyways, I think he took it down for a couple days. He posted a link about it here when he first got the vid... I'm sure you saw it...

Post by **Red-KAT** » Thu Feb 10, 2005 9:23 am

All that $$ and you have an MBC!!! I'm fly down and slap you if ya dont have that AEM running the boost next time.

You a bad bad man!

Post by **hysteria** » Thu Feb 10, 2005 5:47 pm

that's just rediculous

Post by **Red-KAT** » Mon Feb 14, 2005 12:49 pm

You know I notice you are running 500hp on a mustang dyno... What would that come out to on a dynojet? That seems to be what the rest of us use.

Post by **erollinc** » Mon Feb 14, 2005 9:19 pm

wow..... what is all done to this motor? im trying to figure out how you didnt shoot em right through the block hahaha

Post by **rn240sx** » Tue Feb 15, 2005 7:53 am

This 502 rwhp mark.....

IS this Stock bottom end or what..??

Post by **Red-KAT** » Tue Feb 15, 2005 8:07 am

This is one of his rebuilt blocks with forged pistons.. stock crank and stock rods that have been shotpeend. (sp)

It will be nice to see what some forged rods will do for him.

I wonder when the crank will snap?

Post by **Vetal** » Wed May 04, 2005 10:07 am

Don't you guys replace stock rods when you turbo your KA's to lower compression???????

Post by **WDRacing** » Wed May 04, 2005 10:14 am

No, you either add a thicker head gasket or swap in lower compression pistons.

KA stock rod HP limit reached :)

KA stock rod HP limit reached :)

Re: (TrunkMonkey)

Re: (WDRacing)

Re: (IvanAtSPRacing)

Re: (fiznat)

Re: (IvanAtSPRacing)

Re: (fiznat)

Re: (2BN_S13)

Re: (Structure240sx)

Re: (IvanAtSPRacing)

Re: KA stock rod HP limit reached :) (IvanAtSPRacing)

Re: KA stock rod HP limit reached :)

Re: KA stock rod HP limit reached :) (IvanAtSPRacing)

Re: KA stock rod HP limit reached :) (IvanAtSPRacing)

Re: KA stock rod HP limit reached :) (rn240sx)

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