350 for Cobra replica (long!) (the post that is ... not the car)

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02-19-2006, 04:12 AM
spanishdave

350 rebuild for Cobra replica

Hi all .... I am a new member here and would like to get some advice on rebuilding a 350 goodwrench engine.
What it is, I am located in Spain and am just importing a Cobra replica kit from England. I have decided on a small block Chevy over a Ford due to more torque, cheaper bits, more tunable etc. I originally wanted to build the engine myself but when pricing up a stroker crate motor it was working out around the same price as doing it myself. However yesterday I have bought a goodwrench 350 which is in an old chevy pickup which is being scrapped. The engine runs really well and doesn't look too old at all. What I want to do is rebuild the engine for maximum power, spending 3 or 4,000 dollars US on it. The way I have done my Mustang 289 is Edelbrock performer RPM cam, heads and air gap intake with Barry Grant Speed Demon carb. I am tempted to go down a similar road with this but I want to know if there are slightly better heads and I'm sure there is a better cam choice and also should I stroke the engine. I really want to get this right first time as with the ford engine I have had 3 cams, 2 carbs, 2 sets of heads, 3 sets of different rockers .... I'm sure that most of you must have been there in the past :) ..... Any suggestions gratefully received.

Dave from Sunny Spain.
02-21-2006, 10:17 AM
camaro_fever68

Re: 350 rebuild for Cobra replica

Quote:

Originally posted by spanishdave
Hi all .... I am a new member here and would like to get some advice on rebuilding a 350 goodwrench engine.
What it is, I am located in Spain and am just importing a Cobra replica kit from England. I have decided on a small block Chevy over a Ford due to more torque, cheaper bits, more tunable etc. I originally wanted to build the engine myself but when pricing up a stroker crate motor it was working out around the same price as doing it myself. However yesterday I have bought a goodwrench 350 which is in an old chevy pickup which is being scrapped. The engine runs really well and doesn't look too old at all. What I want to do is rebuild the engine for maximum power, spending 3 or 4,000 dollars US on it. The way I have done my Mustang 289 is Edelbrock performer RPM cam, heads and air gap intake with Barry Grant Speed Demon carb. I am tempted to go down a similar road with this but I want to know if there are slightly better heads and I'm sure there is a better cam choice and also should I stroke the engine. I really want to get this right first time as with the ford engine I have had 3 cams, 2 carbs, 2 sets of heads, 3 sets of different rockers .... I'm sure that most of you must have been there in the past :) ..... Any suggestions gratefully received.

Dave from Sunny Spain.

The best advice I can offer on a combo that won't let you down on power for 3-4k is to get a complete Eagle rotating Assembly to make a 383 stroker engine out of the 350 block. You can pick them up on Ebay Stores for under a 1K with cast crank and Hyper pistons. The machine work to bore and clearance the block will run about 500 here. Top that off with a Edelbrock RPM top end kit that includes head, intake, and camshaft which will run about 1500.00 but if your block is a universal, which most truck blocks are, you could go a step better and get the hydraulic roller set up for just a little bit more and be better. The spider and lifter setup is about 200 for the complete kit. Just make sure the lifter valley has the bosses. If you have junk yards in Spain it will be even cheaper as you can get the lifter set-up from a junk car. Edelbrock claim 1.2 hp per cubic inch. That's a dyno proven combo that will keep you from buying parts you don't need.

There are other top end kits availabe that take the guess work out of it but this is one that I am currently running and it performs excellent. It idles about 750 RPM and pulls plenty vacuum. You could drive it anywhere and it has a racy idle.
02-21-2006, 10:42 AM
Bob Parmenter

Before you spend any dough just an observation. And no, I don't give a rip about the usual Ford vs Chevy arguments.

I don't know the European market as well as the U.S. market, but your rationale about building a better engine cheaper with the Chev has one big hole in it. In the world of Cobra replicas, the penalty in value for having a Chev engine in the car is higher than your $3-4K engine cost. Or in other words, every penny you put into the Chev engine you're throwing away. If you can afford to do that it's your call, though not a good econimic choice. Lots of people will tell you to do what you want, it's your car. Though superficially true, they can easily say that because it YOUR money they're throwing away, not theirs.

You may think you'll never sell the car so resale value is of no consequence. Rarely does that happen. Either tastes change, or unexpected circumstances come along, and some day you will likely have to sell the car. In the end you'd get a better return with a Ford engine.
02-21-2006, 11:23 AM
spanishdave

Quote:

Originally posted by Bob Parmenter
Before you spend any dough just an observation. And no, I don't give a rip about the usual Ford vs Chevy arguments.

I don't know the European market as well as the U.S. market, but your rationale about building a better engine cheaper with the Chev has one big hole in it. In the world of Cobra replicas, the penalty in value for having a Chev engine in the car is higher than your $3-4K engine cost. Or in other words, every penny you put into the Chev engine you're throwing away. If you can afford to do that it's your call, though not a good econimic choice. Lots of people will tell you to do what you want, it's your car. Though superficially true, they can easily say that because it YOUR money they're throwing away, not theirs.

You may think you'll never sell the car so resale value is of no consequence. Rarely does that happen. Either tastes change, or unexpected circumstances come along, and some day you will likely have to sell the car. In the end you'd get a better return with a Ford engine.

Thanks for the reply ... I know what you are getting at, and that is what I thought exactly, the thought of putting a chebby in a Cobra horrified me, seeming like not doing the job properly. However in the UK around 75% of replicas have chevy engines in them and the resale value is equal, if not greater than with a ford engine. I will not be keeping the car forever, but don't think that the resale value would be a cent difference. I didn't choose this engine to save money ... just mainly because it seem to be what people want and expect here in Europe. If I was doing an absolute *exact* copy of a Cobra ... yes I would obviously use a ford of the correct age, but this is a replica which is fun to drive and has Jaguar front and back axles, a BMW steering column and a few parts from other cars too .ak sports cars .. so IMHO the engine is no big deal. Anyhow I have never done a Chevy engine before so I hope to learn a lot from the experience. At the end of the day I want a car that is faster than my mate's 454 Corvette (really quick:3dSMILE: ) and I'm sure that I can do it due to the power to weight ratio of my project. What I am looking for is like I said, parts that will work together ... and work together well. Another point is that machining is very difficult over here in Spain ... the last block I had bored to +30 I had to convert to metric with a formula which I got of the internet ... give them the measurements and keep my fingers crossed. That's Spain for you !! All my parts will have to come from the States which gets a bit expensive with carriage and import taxes.
02-21-2006, 02:30 PM
richlo65

here, this website might help....

http://www.ryanscarpage.50megs.com/combos1.html

they have hundreds of differant SBC dynoed combos to look through. good luck.
02-21-2006, 03:18 PM
Dave Severson

:LOL: :LOL: :LOL: Well, look like there's one more going together that will eventually force me to drag that old '85 Vette hulk out and put a Windsor in it.....Really will be fun to take it to the Corvette Rally in Spearfish some day!!!!:whacked: :whacked: :whacked:
02-21-2006, 03:36 PM
Dave Severson

Well, now that you mention it Denny, I do have a 440 Magnum and 4 speed in my collection of mis-matched parts, trade-ins, and left overs...... Could be out at the farm, or maybe in Grandpa's barn, or maybe at my brother-in-laws....It's a thought, though....Thanks man.
02-22-2006, 12:24 AM
spanishdave

Quote:

Originally posted by richlo65
here, this website might help....

http://www.ryanscarpage.50megs.com/combos1.html

they have hundreds of differant SBC dynoed combos to look through. good luck.

thanks there ... this is exactly what I wanted ... and something constructive for a change.
02-22-2006, 02:46 AM
MadMax

Of course it's not "right" to put a Chebby in a Cobra, but even a Cobra with a Ford in it will still only be a replica, not the real thing. I'm from Germany and the market for Cobras here is small, but there is one. And it doesn't seem to make a difference in value if you have a Chevy or a Ford power plant in it. Most Cobras here have Chevy engines in them and parts for Chevy motors are much cheaper and more readily available than for Fords. I would probably go the Chevy way. But that's just an opinion from another Europe-based guy.
As to the engine itself, I can't give you all that much advice, because I'm not in the racing business. If you have 3 or 4k to spend, then I would still check out the price of different parts and get the good stuff for cheap money, then you can buy more good stuff. I'm not sure about the prices in the US, but here it would be cheaper to get for example a Scat rotating assy, costs a good deal less than the Eagle and is the same quality, as long as you stay under something around 600 HP. I would definetly go for the roller setup on cam shafts, they're expensive, but they allow for better flow, because the valves are open high for longer even on a shorter duration cam. As for the heads and exact figures ask the others guys on this forum, they can certainly give you better advice than me. Just wanted to say, 3 or 4k sounds a lot, but you'll see that it's spent much faster than you think if you're not careful.
Hope that helps you a bit,
Mad

PS: A Cobra is a very light vehicle, watch out for traction problems, they're more than likely to occur if your power is too high and the rearend not firmly on the ground. It's not only the weight-power ratio that gets you moving down the track...