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Discussion Starter · #1 ·
i am going to be doing the k24 accord block with k20a2 head and from what i understand i will need to get new pistons since im using the acord block. i want to go ahead and raise the compression to 11.5:1 but i have been having a hard time finding rods. would it be alright to just shot peen the rods to make them stronger? just looking for some options. thanks for any help
 

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Are you going to stay all motor? Why not go with the cp 12.5 compression pistons? The crower rods will work too since they make them for the k24a. Or the eagle rods I guess as well. I am not sure about the clearance.. It really depends on the cams you are going to be running too.

I would replace the stock rods since you have to take them out anyway. I know that means more $$$ but chanced are you are going to rev it past 8200 once or twice :driving:
 

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Discussion Starter · #3 ·
i was going to be staying all motor, but would i be able to run the 12.5:1 compression on CA 91 octane? it will all be tuned with kpro but not sure if that would be very safe especially when i see 100degree+ days. also assuming i keep the stock crank with the 99mm and get new rods and pistons what would be a safe redline? are the eagle rods out in production now? im just not sure what combination to go with since the accord block alaready has clearance issues. i just want to make sure everything is in check
 

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you would really be pushing the limit running 12.5:1 pistons, on 91 octane, and on a 100+degree day. 11.5:1 seems to work really well here in cali and i've seen guys run higher compression here too on 91. everything will all come down to tunning.
 

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What else is going into the motor? 11.1 should be fine and safe. I think if you have plans to toss in some bigger cams this would work well.

My point is go with a safe comp. ratio because unless your going to really build the thing a half point wont yeild really any power gains but would be safer in the long run.

Is the car going to be revved at 8k plus a lot? If its just occasional I think the stock rods should be fine...but if your going to in there swapping pistons and you have the extra cash might as well.

Im not an engine builder but I know a couple guys running stock rods and no problems...yet. One guy rides his motor pretty hard and my business partners car is very adult driven and maintained but sees 8k at autox's and the occasional street race, ok so its not completely adult driven lol.
 

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Discussion Starter · #7 ·
would shot peening the rods be an option? how much does that generally cost. i also want to throw another option out... would i be able to run a moderate amount of n2o with an 11:1 compression ratio with stock rods and aftermarket pistons. just trying to figure out what i want to do by looking at it from every angle
 

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With the k-pro juice is no problem.

Dang I hate to ask this but when you tune for nitrous (even with a k-pro) dont you have to keep the timing retarded all the time and the fuel mixture richer than normal?

Thats what sucks. Youre losing power with the motor until you hit "the button", less power and worse mileage.

EDIT... Heres some information from the Hondata site which to me is interesting.

The K-Pro ECU upgrade is nitrous aware. Arm the nitrous and have the nitrous relay operated on one of several outputs. The K-Pro ECU on switching the nitrous relay will simultaneously retard the ignition and add fuel. A dry kit and bigger injectors are highly recommended although this will drive a wet kit by switching both fuel and nitrous relays simultaneously. This operates in conjunction with any form of NA or forced induction tuning. The nitrous feature will not work on the PRA, PRC or PRD ECU's.
 

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tyflip2 said:
would shot peening the rods be an option? how much does that generally cost. i also want to throw another option out... would i be able to run a moderate amount of n2o with an 11:1 compression ratio with stock rods and aftermarket pistons. just trying to figure out what i want to do by looking at it from every angle
there's no real way to answer the question "would I be able to". It's too dependent on too many different factors. My personal opinion, though? I think it would be extremely foolish not to go to aftermarket rods if you already have the motor apart. If I am going to push a motor to it's limits I want to be confident that everything is built to be strong as fuck because I like to beat the fuck out of it. If you are not confident in your motor when you are driving you won't drive as hard which translates to more hesitation and slower times.

Also how would you feel if you saved the money on rods only to junk your $7000 motor by blowing a rod through the block? I have personally seen four k motors with holes in the block from broken rods. Push these motors hard enough and the rods will break. On the other hand unless you do something very wrong you will not break a Crower, Eagle, etc.

Read that HyTech article in the other post. John from HyTech says that the only weak link in the K series is the rods. Jeff Owen of Special Projects Racing, who is at the forefront of K series developement for road-racing applications, told me exactly the same thing. Why skimp out now and regret it later? Better safe than sorry.

oh and I apologize if that was a rant...
 

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Discussion Starter · #12 ·
that was a very helpful post in my opinion and thank you very much for the facts. i think you helped me make up my mind! thanks also for that info from hondata regarding the nitrous .
 
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