Project "Payback"

[70rs]

OUCH!! That sucks Todd! But at least you caught it before it went south on you and tossed a rod into orbit.

What is the rebuild plan? No time like the present to make a little more power right?

[Spiffav8]

Oh man that sucks! At least you had Aj there to lend a hand. That guy doesn't mess around when it comes to taking stuff apart!

[Vegas69]

So anyway, would the engine have lasted a while? Maybe..... but I wasn't taking any chances of grenading the motor on the road course etc. Now I need to find a reputable engine shop that can blueprint, re balance the crank, hot tank the block, etc. Any recomendations will be appreciated.

Now for the fun part, more compression and a mechanical cam. I'll put it together and make sure it's done right. It will be better. Here is where I stand.

[tones2SS]

Man, it's always something huh, Todd? Sucks about the engine, but at least no major damage. Now you can rebuild it yourself and KNOW FOR A FACT that it is good to go!
GOOD LUCK BUD & cool of AJ to come over and help out!

[70rs]

What is maximum capacity for your block? (CID) I forgot what it's based on.

[waynieZ]

Sorry to hear about this Todd. I bought a Filter Magnet for mine because its been sitting so long, just incase.

[Vegas69]

Originally Posted by Flash68

Bummer man... where do you go from here? Anything happening with the engine builder about this?

I won't even bother to make that call. He said he'd own up to it but I don't believe him and if he did, I'd see my parts in 6 months. It's really not a huge deal. Crank is probably polishable and the cylinders are in good shape. I could redo it fairly inexpensively. If I need new pistons to raise the compression, I may just punch it out to 496. I'm happy with the parts. Most seem high quality. The timing chain was really loose for 3500 miles. It will need to be replaced. If it wasn't for the distributor gear, I think the engine would've lived a long life. I can make a ton more power with what I have in mind and be just as streetable. Stay tuned....

[skatinjay27]

Originally Posted by Vegas69

I can make a ton more power with what I have in mind and be just as streetable. Stay tuned....

NICE!any thing under 750 will be too low!lol

[GregWeld]

Todd --

Now you've managed to ruin my Hawaiian vacation! OUCH!

Want to haul it to Phoenix call Bob Ream at Imagine Injection tell him I sent ya...

I've had at least TWO motors built by dickheads - one was Dougs Racing Stables -- the shims under the valve springs didn't have pockets - so that motor was junk before it made it off the dyno... Been there done that!

[Cris@JCG]

Todd 10 lbs residue valves & springs behind the pistons will not help your knock back issue.. I worked for Wilwood in the research & development dept for 10 yrs!!!

I have asked you to send me in all your specs on your whole complete brake system.. Pics I am pretty sure I can help you resolve your issue!

You will create brake drag with residue valves or springs behind your pistons!

Residue valves were built into OE master cylinders when drums were standard equipment on cars.. they consists of a one way valve.. which held pressure when drum brakes retacted back from when pedal was released.. They are also heavily used when a master cylinder reservoir sits below level of the calipers @ the wheels.. When the reservoir sits below level of calipers the brake fluid will drain back into the master cylinder reservoir.. 10 lbs for drums & 2 lbs for disc brakes..

Springs behind pistons have not been used for a long time in production OE cars.. The caliper designs of today do not require them.. I remember when Wilwood used to use them on Winston Cup calipers 15 yrs ago for the same purpose that you are stating of eliminating piston knock back or when the caliper that were used from 65 to 81 Corvettes(J52 option if I remember correctly).. Cup seals with a piston design that would float in piston bore.. Piston to seal design has come a long way since then..

Steve Rupps Bad Penny ran Wilwoods for some time... He has never complained about piston knock back to me!! He is running Baers on Penny now but not cause they were a bad brake system with issues!!

Originally Posted by Vegas69

Just lucky I guess. It's not as rare are you think. There are 4 fixed calipers and 275mm/335mm of R compound that will pull more G's than most sports cars. It stresses everything. I bet a 10 psi residual out back will fix it, I'm just worried about excess heat. I've also considered doing springs behind the caliper pistons like they did in the old days. Wilwood claims it won't work, but I don't think they want the liability of telling me to mod my calipers. The other alternative is a floating rear end. Power brakes with a larger piston would help dramatically but I don't make enough vaccum. A hydraboost unit would also allow a bigger piston and would help dramtically but I like manual brakes on the race track. I know how to fix it, it's just at what compromise and how much money I want to spend.