Crate engines- tq. vs. hp.

[Scooter76]

I am extremely happy with my 76, but one area that it is lacking is the power department. I have decideded to pull & store the L48 & replace it with a Gm crate motor. My car is a th/350 with a 3.08 rear gear which I do not plan on changing. Also I am not out to make a screaming hot rod out of it. I have narrowed my selection down to 2 engines, (1) Fast burn 385 385hp @5600 & 385 ft.lb @ 4000 rpm. (2) Scoggin dickey offers a vortec style engine with 330hp @ 4800 & 404 ft.lb @ 3800 rpm. The vortec motor doesen't have as stout internals as the FB. motor, but is considerably cheaper than the FB & has a hyd. roller camshaft which I am sold on because you can keep the specs. mild & still make good power. I am really thinking that since I am not out for ultimate hp. & will still be running the 3.08 gear that the vortec motor would probobly be actually a better choice for my intended combination. I think that the extra torque at the lower rpm would help pull the 3.08 gear better. I could mod the L48 but it is a 77k motor & also I would like to keep it in tact. I like the idea of having a brand new one in my Shark. Sorry for the book here, any input will be deeply appriciated.

 

[Redmanf1]

I think that I would go with the fast burn. It will have plenty of torque with the 3.08 and if you want to use it for something else down the line it will have the good parts. Also if you want to sell it later on it will sell better. Just my 02

 

[69autoXr]

You should also consider the ZZ4 or the HT 383. The ZZ4 makes 20 more ft. lbs. of torque at 500 less rpm than the Fast Burn, but 30 less hp than the Fast Burn. More power and torque than the Scoggin Dickey you mentioned. By the way, the Fast Burn and the ZZ4 have the same, hydraulic roller cam, which you mentioned you wanted.

If you want the ultimate in small block crate engine torque, look at the HT 383. This would be perfectly suited to your 3.08 gear, and it makes 435 ft. lbs. at 4000 rpm. 340 hp isn't bad either, but with all that low-end torque you'll burn your tires forever. Also has a hydraulic roller cam.

Chris

 

[MaineShark]

If you plan on keeping your original transmission in the car, you might want to watch how much torque you apply, or you may end up with a short-lived bit of fun. I think 400+ ft-lbs justifies a rebuild, or possibly a new tranny. Hopefully someone with a bit more expertise than I will chime in.

Joe

 

[Scooter76]

Thanks for the suggestions, I am also looking at the ZZ4 also. The reason that I was looking at that Vortec motor is the price, $2200, vs. 4200 for the FB. The Vortec is less intake, dist, flexplate, balancer etc. so it would end up being about 2600 or so. What stinks is that Scoggin- Dickey is about 1 mile from my house so no shipping, but got to pay sales tax. Today I am leaning twords the ZZ4 but I am changing my mind like the proverbial wife, on this engine stuff. Thanks agian for the suggestions.

 

[bossvette]

the HT383 is a good choice to me especially if you can pick it up locally (sales tax-shipping whats the difference)
torque is what we feel when we are driving and with a 3.08 you need all the torque you can find. when the engine is out an OD trans is easy to slip on the back and will make your new engine perform that much better

 

[Scooter76]

Thanks for the input. A new trans is'nt in the budget right now, so we will have to see if the th/350 can last a while. Thanks agian. DECISIONS-DECISIONS

 

[Jack]

the HT383 is a good choice to me especially if you can pick it up locally (sales tax-shipping whats the difference)
torque is what we feel when we are driving and with a 3.08 you need all the torque you can find. when the engine is out an OD trans is easy to slip on the back and will make your new engine perform that much better

Ditto on the HT383 & its torque & your 3.08:1.
JACK:gap

 

[bossvette]

since you have an auto a 700R-4 is not all that expensive to find used a $50 wire kit from Painless wireing and you have a lower first and OD shorten your driveshaft $30-50 I paid $250 for a 700R-4 several years ago. The manual OD trans are the expensive ones

 

[RLE80L48]

Not to change the subject BUT, Whats involved in building a 383? Where can I find out the facts and info? I would like to try and build one myself but have no clue. I have a good 010 4 bolt block.Whats next?

 

[bossvette]

a 383 is a 350 block bored .030 over with a 400 crank. now a days you can buy off the shelf cranks that are ground and balanced for the 383 with 5.7 rods. when I built mine the only ones availabe were high doller stroker cranks I am runnung a stock chevy 400 crank that has the journals turned down to 350 size both mains and rods. You can use a 400 crank and 400 rods with 350 pistons to do it on the cheap but most people prefer the longer rods. there is some clearanceing involved but not as much with a "383 Crank" as a stock crank
you may have to clear the rods or get a small base circle cam if you go wild with the cam I am runnung a stock base circle .485/.505 lift cam with with clearanced rods
Just assemble the the motor piston by piston and make sure you have 1/16+ clearance everywhere

 

[DR.68]

I put the FB in my 68. I am very happy with the power.

But is it ever enough, I'm already looking at adding the
HOT CAM.

 

[69autoXr]

Hot Cam in Fast Burn

Let us know how it is. I was thinking about the Hot cam in a 383 with the Fast Burn heads, I wonder how it would run.

 

[gooney0]

.02

I had a ZZ4 put in my '72 4 speed a year ago. I am VERY happy with it.

It has a little "lope" to it at idle, not too much but you do feel it a little.

The torque is NICE. (the muncie helps with that too) I think I have 3.08 or 3.36 gears. Probably 3.08

No matter what gear or RPM you have more than enough power to pass people.

The car rocks back when you hit the gas. Not an easy thing to do in a vette.

Makes great doughnuts

Gets about 10mpg on the highway, and takes only 93 octane :-(

I haven't raced it, so I don't have any hard numbers for you. I wasn't looking for a HP monster either... The ZZ4 is nice because it is already assembled and you know what you're gonna get.

Here is my setup:

ZZ4
Stock ex. manifolds
2 1/2 pipes no cats (1972)
Stock-like mufflers

Original points distributor recurved.
Holly 600cfm carb.

Thats it. I don't know if I get all 355hp since i'm not using the HEI the motor came with, nor am I using headers. The nice thing about 355hp motors is you can afford to "give away" horses!

If I lose 50hp on the manifolds... I still have 305hp and most of the 406ft/lbs

No problems so far... runs like a CHAMP.


-Gooney0

 

[Crickett]

I've got a fastburn that's being put into my 76 as we speak. I'll letcha know how things go!