1968 Fastback 351w Engine Rebuild Questions

[philly4lyfe]

I have a few questions about which direction to take my new project.

I am purchasing a 1968 fastback from a guy who is abandoning the project. I am looking for suggestion on which way to go for my power train.

First I'll give you some background. I have basic mechanical skill but no training. I have changed brakes, rotors and installed a cold air intake on my car but nothing major. I am willing to learn as I go and can dedicate some time but not a ton.

The car comes with a 1978 351 windsor. The guy says it is in working order but he planned to machine it to a 357 and rebuild it. It is already torn down to the block. It comes with GT40 heads as well. It is converted to a manual and already has a clutch cable.

Based on the research Iv'e done, I planned on either mating it to a tko 500/600 or t56 if I can find one for a reasonable price.

I am a spirited driver and may take it to the track for fun but no drag racing. My other car has about 300 HP and based on that I probably want to be in the 350 range. I will use it as a weekend driver.

So my question is should I convert the 351 to a roller? How much would this rebuild plus transmission and adapters cost? Is it better to find a junked 2001+ GT and take the engine and 3650 tranny or t56 if I can find a cobras as a setup? For me in order of importance are reliability, performance, fuel economy.

Thanks for your help.

 

[Cheapsnake]

I've got a 351w with a Tremec 3550 in my Cobra replica and it's sweet combo. 350 very steetable and reliable HP is a piece of cake for these engines with a good cam, headers and easy breathing heads. The GT40 heads are a popular choice, but I think they need their own special headers. I'd go with roller rockers, but don't think you need a roller cam for a mild cam and 350 HP. Just make sure you use a zinc-rich oil to protect your cam and lifters. If you do the rebuild yourself you should be around a grand (bearings, rings, rockers, pushrods, gaskets, etc.), assuming you don't need a lot of machine work. You're gonna love that Tremec. Good luck.

Tom

 

[RacerJames]

The engine in a 2001+GT won't fit in your '68 engine bay without major (read expensive and time consuming) suspension and body mods.

350 hp is easy to get from the flat tappet motor you have, the heads and intake are key. Put flat top pistons in it and you'll be at 9.5 to 1 compression, and with a cam Like the Edelbrock Performer (266/272 210/[email protected] I..469/E.484 116LS) You'll be running just fine.

I wouldn't rollerize an early W block. if you can't live without roller cam, It makes a lot more sense, and is more reliable, and easy to fix if it breaks, to find a junkyard block from an '87 or later pickup (F-150, 250, 350). If you go this route, then the B-303 Cam from Ford (or equivalent) is the way to go.

I'm researching trannies myself, so I don't have any useful comments on that front.

 

[barnett468]

I have a few questions about which direction to take my new project.

I am purchasing a 1968 fastback from a guy who is abandoning the project. I am looking for suggestion on which way to go for my power train.

First I'll give you some background. I have basic mechanical skill but no training. I have changed brakes, rotors and installed a cold air intake on my car but nothing major. I am willing to learn as I go and can dedicate some time but not a ton.

The car comes with a 1978 351 windsor. The guy says it is in working order but he planned to machine it to a 357 and rebuild it. It is already torn down to the block. It comes with GT40 heads as well. It is converted to a manual and already has a clutch cable.

Based on the research Iv'e done, I planned on either mating it to a tko 500/600 or t56 if I can find one for a reasonable price.

I am a spirited driver and may take it to the track for fun but no drag racing. My other car has about 300 HP and based on that I probably want to be in the 350 range. I will use it as a weekend driver.

So my question is should I convert the 351 to a roller? How much would this rebuild plus transmission and adapters cost? Is it better to find a junked 2001+ GT and take the engine and 3650 tranny or t56 if I can find a cobras as a setup? For me in order of importance are reliability, performance, fuel economy.

Thanks for your help.

hello;


rollers are nice on builds like this but not necessary, however, a non roller is highly sensitive to break in. it must be done correctly.

aluminum heads should be used on any build. i would use afr 185 to get your hp numbers.

keep your dynamic compression [not static] at around 8.5 for 91 - 93 octane.

you can buy a stroker kit for that too.

the 600 has a far better gear ratio than a 500.

 

[philly4lyfe]

hello;


rollers are nice on builds like this but not necessary, however, a non roller is highly sensitive to break in. it must be done correctly.

aluminum heads should be used on any build. i would use afr 185 to get your hp numbers.

keep your dynamic compression [not static] at around 8.5 for 91 - 93 octane.

you can buy a stroker kit for that too.

the 600 has a far better gear ratio than a 500.

What process is involved in breaking a non-roller in? If properly broken in, will I get the same reliability as a roller?

 

[barnett468]

What process is involved in breaking a non-roller in? If properly broken in, will I get the same reliability as a roller?

hello;

well if you run a massive can, you need to run light springs for break in then change them. you can also send the cam out for break in.

you need to set the timing

adjust valves

prime the engine with either cam.

use cam oil not grease on cam and lifters.

i remove the thermostat.

make sure there is gas.

put a big fan in front of radiator.

start it up.

instantly rev it to 2000 and let it run for 30 minutes.

after a few minutes, it bwill run faster, just reduce the rpm to 2000.
.

 

[RacerJames]

When you buy a cam and lifter set, the manufacturer usually provides break in procedures. Follow them. Roller cams became the norm in the late 80s. Before then, engines were going half a million miles without rebuilds. A roller is better because of cam profile and less friction, not necessarily because of longer life or reliability.
We ran flat tappet cams in all our stock cars because the rules specified them to keep costs down, and to keep HP under control for safety reasons. We raced the same 302 with a .500 lift cam for 5 seasons. Never had any problems.
We ran flat top pistons and 68cc heads and also never had any trouble with running 87 octane pump gas in it. That's about 9.5 to 1 compression ratio. Back in 89 or 90, I remember reading about 9.5 to 1 being optimal for a street engine on pump gas in Hot Rod magazine.

 

[horse sence]

I always lube a flat tappet cam very well ,to much is not enough. use a good break in lube . The lifters need to be submerged in oil and pumped a few times .lube the lifters with cam lube before you drop them in . PRIME the motor before starting .I will prime one for a good 10 minutes ,you want to see oil come out of every push rod and not hear air spurt out ,It's a good idea to have an oil gauge hooked up . I have never had a cam round off but the only brands i have ever used is Comp cams and Crane ,but mostly Comp cams .280 H is my favorite comp cam for a fair daily driver ,slight rough idle ,but the 292 H or S/solid like i have in me 69 351 makes the Horses .

 

[RacerJames]

Priming the engine oil system is key for a good break in. Priming means to put oil in the pan once the engine is built to the point that the oil pan is on it. Usually, priming the oil system happens after the engine is in the car. I have done it with the engine on the stand though, just in case I find a problem. I use a drill motor with an extension and socket to turn the oil pump through the distributor hole. Spin the pump like Jim says, til the oil runs through each rocker arm.

 

[horse sence]

If you have an old distributor you can pull the shaft out of it and strip off the oil pump cam drive gear and the advance mechanism ,i have one for each size drive shaft .
I built a start up stand ,it's nice to be able to start the motor outside the car .Then if you should have a problem it is much easier to deal with .
I break my motors in on the stand before i put them in the car and they are ready for fun.