Lifetime of small block 427w

[Ace23]

Looks like another unexpected opportunity to own a Cobra is knocking back at my door. This particular car is the one I always keep going back to in regards to fit, finish and color scheme so I think I'm going to take the plunge. Having never owned one I had a question in regards to the powertrain. This specific car has a KC 427 and I believe it is the Steet/Strip 585hp/565tq crate engine. I know there are many factors that play into lifetime of an engine but what can one expect out of a setup like this. As far as I know the car has 12k miles on it and has not been used as a track car just a street car. It has had its regular oil changes, never any issues and hasn't lived its life at 6k. Looking to gauge potential wear and tear items at this mileage. From what I can tell it has been properly cared for.

[Grubby]

Engine life is likely many more miles than you will ever drive the car.

Most Cobras only get a few thousand miles per year.

John

[olddog]

From my perspective a high performance engine verses a factory family car engine is a double edged sword, from a reliability point of view. Typically a good builder improves the oiling system and puts in more durable parts (likely to balance it better too). So the rotating assembly should be much stronger to take the intended abuse.

On the other hand, to get more power, more radical cams, with higher valve lift, are used. Then stronger springs are needed. I have seen radical racing setups that they loosen the rockers in the off season or just change the springs out each season. Letting an engine sit in one spot over the winter leaves a couple valves open. That is a long time to keep a spring compressed. From my perspective the springs are taking a beating over time, not miles. Now that assumes it is not getting revved up until the springs are dancing violently, which can take its toll in minutes.

So, I generally worry about valve train stuff the most. The more radical, the more concern. That assumes that everything else was done well and there are no issues with fuel washing down cylinders.

[mikeinatlanta]

I think olddog nailed it. I have a 432 small block built with very high quality components that should really last, however, my .700 lift cam means that I need fresh springs at no more than 1000 mile intervals. Of course all depending on how high and how often I rev it, but even if I don't rev it, the cam is hell on the springs.

[Ace23]

Originally Posted by olddog

From my perspective a high performance engine verses a factory family car engine is a double edged sword, from a reliability point of view. Typically a good builder improves the oiling system and puts in more durable parts (likely to balance it better too). So the rotating assembly should be much stronger to take the intended abuse.

On the other hand, to get more power, more radical cams, with higher valve lift, are used. Then stronger springs are needed. I have seen radical racing setups that they loosen the rockers in the off season or just change the springs out each season. Letting an engine sit in one spot over the winter leaves a couple valves open. That is a long time to keep a spring compressed. From my perspective the springs are taking a beating over time, not miles. Now that assumes it is not getting revved up until the springs are dancing violently, which can take its toll in minutes.

So, I generally worry about valve train stuff the most. The more radical, the more concern. That assumes that everything else was done well and there are no issues with fuel washing down cylinders.

Thanks for the opinion. I'm not sure what cam this motor has in it but I believe it's a hydraulic comp that is probably not to far off from what normally goes in this Keith Craft setup. I believe the current owner has put about 8k trouble free miles since he's owned it and it's a street setup. Obviously has some cam in it but nothing to radical. I guess I should get hooked up with someone that can help me learn a bit about maintaining a old school motor. I don't want to get much more involved than oils changes, performing a leak down, plugs ect. I want to spend my time driving not wrenching. Car is definitely sorted and I know you will be turning a wrench here and there that's just the norm. I guess like anything regularly cranking it wouldn't be a bad idea either. I'm from the younger demographic who has only had fuel injection vehicles.

[Dwight]

Keith's street / strip motors are mild.
Find a shop that can tune the carb for you. In Memphis that will not be hard to do.
I think the motor will last for 10s of 1000 of miles for you on the street.
Biggest problem for card'ed motor is poor tuned carbs that wash down the cylinder walls, speeding up ring wear and contaminating the oil.

You can always call Keith and talk to him or one of the guys in the back that build motors.

I see you live in Memphis about 3 hours west of Florence, Al.

We have an active group of Cobra in North Ala and Tenn. Maybe you can join us sometime. We have a few injected Cobras and lot of carb'ed ones. Coach Mike is our carb tuning guy.

Dwight Frye algunruner@aol.com

[Ace23]

Originally Posted by Dwight

Keith's street / strip motors are mild.
Find a shop that can tune the carb for you. In Memphis that will not be hard to do.
I think the motor will last for 10s of 1000 of miles for you on the street.
Biggest problem for card'ed motor is poor tuned carbs that wash down the cylinder walls, speeding up ring wear and contaminating the oil.

You can always call Keith and talk to him or one of the guys in the back that build motors.

I see you live in Memphis about 3 hours west of Florence, Al.

We have an active group of Cobra in North Ala and Tenn. Maybe you can join us sometime. We have a few injected Cobras and lot of carb'ed ones. Coach Mike is our carb tuning guy.

Dwight Frye algunruner@aol.com

Dwight,
Are you talking about having the car tuned on a dyno or just having someone who knows carbs change the settings? Memphis isn't the hot bed it used to be for performance cars but I'm sure there finding a few folks who know carbs wouldn't be to hard of a task. I've ridden in the car a few times and it seems to run great but that isn't to say I couldn't check it out. Good to know you guys are over that way. I know of a handful of cars around here and maybe we could arrange a meet one day.

[Ace23]

Have had the opportunity to take the car out twice. Seems to run pretty good and is smooth from 2k to redline. I kinda go by the if it ain't broke don't fix it rule but I would like to put in on the local dyno and see what it puts down rwhp wise and more importantly what the A/F is. Will be interesting to see the results and what steps can be made to improve on anything. The carb is a Holley Avenger and I think it's a 750. Lots of talk lately about the Q-Fuel setups and using mechanical secondaries.

[Dwight]

We have two guys that are great at tuning carb's. Coach and Eddie

Sure we need to hook up. Maybe a cruise to somewhere in Miss.
April 25 th we are driving to Bowling Green KY to meet up with the KY Cobra Club.
We try to go to Chattanooga once a year to a cruise at Honest Charlie's / Coker Tire.
Then in June we convoy to Ohio for the London Cobra Show.

Keep in touch.

Dwight

[LMH]

Is it a production block or after market block? A 427W built on a production block will probably not last as long with the long stroke. After market block would probably last longer as it can have the larger bore and not as long of a stroke.
Larry

[DAVID GAGNARD]

Just for the sake of argument,let's say a well built 427W is good for 50,000 miles with routine maintinence assuming it is street driven and not drag raced and flogged to death........and in my opinion I think 50,000 miles would be very accurate,actually believe it would should go more than that,but lets use 50,000 miles as a base...........

How many miles do you really think you will drive a Cobra per year????
Your first year,it's new to you and you love it, you'll likely put anywhere from 3,000 to a high of maybe 7,500 miles on it depending on where you live and your normal climate......after the first year, your mileage will slowly decrease to probably an average of no more than 3,000 miles a year,do the math,how many years will it take you to hit 50,000 miles????

Using my numbers your looking at somewhere around 15 years!!!!!! will you still have that Cobra in 15 years??????

I wouldn't worry about the life span, just drive it/enjoy it and maintain it and it will be fine......

of course,all this is my opinion only and that and a dollar will get you a cup of coffee in downtown Marksville on any Saturday morning........

David

[Ace23]

Originally Posted by Dwight

We have two guys that are great at tuning carb's. Coach and Eddie

Sure we need to hook up. Maybe a cruise to somewhere in Miss.
April 25 th we are driving to Bowling Green KY to meet up with the KY Cobra Club.
We try to go to Chattanooga once a year to a cruise at Honest Charlie's / Coker Tire.
Then in June we convoy to Ohio for the London Cobra Show.

Keep in touch.

Dwight

Dwight,
Yeah maybe we could get a group together and try to mmeet in Tupelo or something. Sounds like you guys do some pretty good road traveling. I plan on talking to the dyno shop in the next few days and see about putting it on there to get the A/F checked. It sure would give me a whole lot more direction than just guessing. Should be able to put some gas in it this Sunday and calculate the MPG that its turned out so far as well.

Originally Posted by LMH

Is it a production block or after market block? A 427W built on a production block will probably not last as long with the long stroke. After market block would probably last longer as it can have the larger bore and not as long of a stroke.
Larry

Its a Keith Craft 427 Dart block setup

Originally Posted by DAVID GAGNARD

Just for the sake of argument,let's say a well built 427W is good for 50,000 miles with routine maintinence assuming it is street driven and not drag raced and flogged to death........and in my opinion I think 50,000 miles would be very accurate,actually believe it would should go more than that,but lets use 50,000 miles as a base...........

How many miles do you really think you will drive a Cobra per year????
Your first year,it's new to you and you love it, you'll likely put anywhere from 3,000 to a high of maybe 7,500 miles on it depending on where you live and your normal climate......after the first year, your mileage will slowly decrease to probably an average of no more than 3,000 miles a year,do the math,how many years will it take you to hit 50,000 miles????

Using my numbers your looking at somewhere around 15 years!!!!!! will you still have that Cobra in 15 years??????

I wouldn't worry about the life span, just drive it/enjoy it and maintain it and it will be fine......

of course,all this is my opinion only and that and a dollar will get you a cup of coffee in downtown Marksville on any Saturday morning........

David

David,
Thanks for the opinion.....I'm not so much worried about it but was just curious of how long they could last. My car will see alot of cruising probably living the majority of its life between 2K-4K and then the occasional hard pull. Can't do much more than keep the oil changed and regularly drive it

[Ace23]

Did get around to looking through the booklet that came with the car.I have every receipt for everthing that has ever been done to the car and a full build sheet from Keith Craft on the motor and everthing in it....pretty nice. Looks like the cam is a Comp hydraulic roller says 252-262 with 576-576 and 112LS. I'm sure I can take all this information and put it to good use when I begin the process of making sure everthing is setup as good as it can be

[LMH]

Dart block built by KC... I wouldn't be concerned about longevity at all. Sounds like a great engine!
Larry