trying to settle on a plan

So I've gone and racked up 174,000mi on my cobra. She's still running strong, but an oil leak has developed at the rear of the block and I'm thinking I should have a plan for the near future. I would love to throw in a 347, but realistically it's a street car and a 302 will be plenty of fun in the canyons.

So my debate is this, should I;
A. Rebuild my 302
B. Find a junker with low miles and clean it up
C. Go for one of those $699 short blocks from LMR

My plans would include porting my cobra lower, a set of nice aluminum heads(most likely AFR 165's because they'll pass emissions and flow nice), and have a custom cam ground. I intend on keeping it NA. What size throttle body would be appropriate for such a combo? Will my 24# injectors be adequate? Should I just have a chip burned to handle my tune? I'm not trying to build a beast here, just something fun to drive that I can get good reliability out of. It's not my dd, but I want to be able to drive it every day if I feel like it. If I get it tuned up right I would imagine this would give me 300hp easy with nice torque across the board. Then I can blow some coin at Maximum Motorsports on suspension goodies since they're only 15min away from me:D.
 
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It sounds like you have the plan you want for the car already, and that's the hard part of the plan.

Now, it just seems you need to figure out how to make that plan a reality; via finances, logistics etc.

But, like COBRA90GT said, is it the rear main or something else? The issue may not be as bad as you think...
 
So I've gone and racked up 174,000mi on my cobra. She's still running strong, but an oil leak has developed at the rear of the block and I'm thinking I should have a plan for the near future. I would love to throw in a 347, but realistically it's a street car and a 302 will be plenty of fun in the canyons.

So my debate is this, should I;
A. Rebuild my 302
B. Find a junker with low miles and clean it up
C. Go for one of those $699 short blocks from LMR

My plans would include porting my cobra lower, a set of nice aluminum heads(most likely AFR 165's because they'll pass emissions and flow nice), and have a custom cam ground. I intend on keeping it NA.
What size throttle body would be appropriate for such a combo?
This is always debated. I would open up your cobra upper intake to at least 70mm, 75mm would be fine as well.
Will my 24# injectors be adequate?
If I were you I would use them, if I had a GT I would upgrade to 30s. Take that how you would.
Should I just have a chip burned to handle my tune?
Plan on having a chip burnt or self-tuning it.I'm not trying to build a beast here, just something fun to drive that I can get good reliability out of. It's not my dd, but I want to be able to drive it every day if I feel like it. If I get it tuned up right I would imagine this would give me 300hp easy with nice torque across the board.
At that point the cobra intake is your limiting factor; AFR165s and a custom cam can easily support 300rwhp. Talk to your cam grinder about your choice of intakes. Then I can blow some coin at Maximum Motorsports on suspension goodies since they're only 15min away from me:D.

Answers are in bold.

Adam
 
sounds like the rear main seal. i'd fix that before you plan any further. not really practical to go out and buy a new block or rebuild it if it all needs is a new seal. that's a bunch of money towards the heads.
 
Thanks for the replies guys. As fort the oil leak, I'm not positive. I've had my Toyota torn apart for the last few days, so I haven't had a chance to accurately diagnose the Cobra. How can I be sure it is the RMS? What else should I check that could look like a RMS leak(oil pan, intake to block...)?

If it is the RMS, would it make sense to just go ahead and do a rebuild since it has such high mileage? Or should I just drop the tranny and replace the seal and hope I didn't screw up the clutch too bad with the leaky seal?

Thanks again guys!

-Lorenzo
 
Sounds like you have a great plan. 24 lbers will be fine. I like the fact that you are going reasonable on the bottom end and spending the money on a good set of heads. I don't know how many threads have been on here lately where someone wants to build a big forged stroker bottom end with a set of some factory iron heads. I'd spend the extra money on a good cam, and a decent tune. I wouldn't go crazy on the tune. You can almost get away with a stock tune, so don't go out and spend a grand on a dyno. That low cost kit from LMR looks really good. 70mm throttle body will be more than adequate.

Kurt
 
Thanks for the replies guys. As fort the oil leak, I'm not positive. I've had my Toyota torn apart for the last few days, so I haven't had a chance to accurately diagnose the Cobra. How can I be sure it is the RMS? What else should I check that could look like a RMS leak(oil pan, intake to block...)?

If it is the RMS, would it make sense to just go ahead and do a rebuild since it has such high mileage? Or should I just drop the tranny and replace the seal and hope I didn't screw up the clutch too bad with the leaky seal?

Thanks again guys!

-Lorenzo

I just bought a 1989 25th anniversary edition convertible with 177K on the engine and transmission. The car runs great, shifts great, etc. I take it to work as a daily driver, no issues. I am planning the differential/transmission/engine rebuild after my taxes next year. I've heard of these engines running near 300K miles but in my mind that's just too high. For peace of mind, in my opinion, I'd rebuild it anyway.

Adam
 
Thanks for the replies guys!

Thanks Kurt, I figure for my purposes, stroking it out isn't really cost effective at this point. I'd have to go for a new intake, bigger injectors, more serious tuning all on top of the bottom end work. If I can get into the 300rwhp realm with a nice broad torque curve I'll be happy. Then I'll worry about making this thing corner better for a while.

What direction tuning wise would make the best sense in my case? Should I go for a mail order chip, or look into something like a Tweecer or PMS?

Hey Adam, that's a good thought about waiting until tax return time. I should be able to collect the heads, cam and get the supporting stuff by then. I guess for now I'll worry about fixing the seal and collecting parts.

Thanks again guys!

-Lorenzo
 
Stroking it without putting enough heads and cam to go with it is pointless. I think a 306 is a much better choice for you. Sounds like a great plan.

Kurt