erika1977

ok guys-lets get your opinion--after reading everything i could, and with all your suggestions, i looked into the http://www.allchevyengines.com website and found two motors i really like----now you chose the one for me!!
the 383/430, or the 406/435........however i notice on the 406, it is a 2 bolt main----what does that mean----can i still use it? also which stall do i want for my trans? i'm keeping my 308 gears.--PLEASE DO NOT TALK ME OUT OF ONE OF THESE AND TELL ME ZZ4--i want to be differant!!--the choice is now up to you--I HAVE NO REASON NOT TO VALUE YOUR OPINION!!!!!! :seeya

Tominator

Actually for streetablitiy I would go with the 383/410 hp option. I know that's not one of your options but street light to street light it would be my choice.

I know more HP is always cool but the one engine you list runs best between 2500 RPM and up, that's high for the street. Also talk to the builders and tell what gears your running and see what they think.

erika1977

ok, what do you mean streetability? will it be squirrely off the line, or just when i jump on it---if it is when i jump on it, thats what i want. :seeya

Fevre

A car that is built for high rpm's will cough spit and sputter at low rpm's but will go like heck when rev'd up. If you like to drive around with out reving real high, get a engine built to run for your driving characteristics. Post you transmission type, rear end ratio and driving style and you will get a lot of input about the engine set up.

erika1977

this is probely a stupid question, but wouldn't the stall converter take care of the cough and sputter at low r's?

Fevre

If you have the right one it will keep your car from stalling out at low rpm's. I am no expert but I know that if you buy/build an engine to run at let's say 2500-6500 rpm's you better keep it in up in that range it it will run poor and or rough. That is what Tormintor was getting at by streetable. 2500 rpm's is pretty high for a car that is used to cruise around, not just taken out and ran pretty hard. If you like to cruise around I do, you would be better to have a car that runs in the 1500 to 5500 range. I like to be able to run it at about 2000 rpm's with out is struggling to run smooth. I think I am going to build a big block Camaro or Chevelle with more umph so I will have to run it higher in the rpm range. For my vette cruising around it what I like to do with and occassional rev up to 5000 rpm's or so. I am going to rebuild my 383 which will give me more torque in my driving rpm range. The 383 that Tormintor regomended would be an excellent engine for someone who likes to drive around and get on it just once in while. How do you like to drive you vette? Or should I say how do you want to drive your vette?

dladd74roadster

Erika, the above posts are correct. If this car is going to spend 99% of it's time on the street, you want to buy an engine that has it's power band in the lower range. The purpose of a stall is this: a high duration cam typically used in higher rpm engines won't idle very well below 1000 to 1500 rpms. A stall converter engages at a higher rpm allowing the engine to be idled up while in gear and not moving. If you use a large duration cam without a high-stall converter, it won't idle. You will put it in gear and it will die. The reason for this is that the cam doesn't produce enough vacuum at low rpms.

A stall converter won't make up for your rearend.

Now for my opinion on engine choice. Choose one with a little less hp but with more low-end power and torque. If you choose a high rpm engine and keep the 3.08s in the rearend, it is going to be a dog off of the line. If you choose one with a lower powerband, it will help make up for the rearend but only partially. You stated that you want it to be squirrly off of the line. You need an engine with a healthy dose of low-end torque (powerband from 1000 or 1500 up to 5500 or 6000 rpms) and I would also suggest at least a 3.55 gear. All of this can be accomplished WITHOUT a stall converter. You can put the money from the converter toward the gear. I think that would be a more efficient use of the money.

Hope this helps.

dl

John W

I guess that I am a bit confused here (and gonna be longwinded):

If the idle can be set so that the car can idle in gear, does it really matter if the "powerband" is at 2500+ rpm. From the graph (of the 383/430) the engine is making 400+ ftlbs of torque and not really nosing down as you move to the left. It seems to me that 400 ftlbs of torque is enough to shred the tires at will. The graph seems to indicate a well matched combo.

I could see a problem with a smaller/less torquey engine (say a 302) that at 2k rpm makes say 150 ftlbs but can rev alot and makes max power (say 400hp) at 7500rpm (which by my calculations is ~280 ftlbs of torque). This engine would have a tough time moving a 3000+lb car from a standstill at low rpms.

So how can you tell an engines characteristics given only a graph?

The graph of the 383/430 looks similar (shapewise) to an engine I have in a 1996 Z28, very flat and very broad. The difference is that the Z's engine puts out less torque (rw in the 310 region), and that car drives fine. Of course there may be a difference in final gear ratios for first, but with 30% more torque and less weight I think they more than equal out.

Help me out here.

John


[Modified by John W, 7:44 PM 5/10/2002]


[Modified by John W, 7:46 PM 5/10/2002]

dladd74roadster

You can't tell that much about engine characteristics by looking at a graph except that you are looking for a flat torque and hp curve. You are also looking for where the peaks plot in relation to RPM. The statement by the builders that the engine's effective RPM range is 2500 to 6500 indicates that the engine has a fairly long duration cam. Heck, that 406 has a 292 cam in it. That's a lot of duration and will definately have to have a stall. My comments about the stall were only to clarify that an engine with a large cam won't spit and sputter at low RPMs, it will either idle or it won't while in gear.

The engines in question are both a little long on duration for street driving with a 3.08. Now don't get me wrong, either of these engines would be a great choice in combination with a 2500 stall and a 3.55 or 3.70 gear. That thing would leave like a monster and pull strong all the way up to 6500 or so. But without the other pieces, I think Erika will be a little dissapointed in the low-end performance which is what, judging by her comments, she is after.

dl

Fevre

Look at this way, a car can show good horsepower and torque numbers on a graph but run like crap. If the car is set up to run at 2500 to 6500 rpm's it will run best in that target rpm range even if it shows pretty good numbers on the graph below and above those rpm's. Ever hear a top fule dragster at idle on the line. It is running pretty high rpm's but still coughing and spitting and struggling to run. If the guy/gal pops the clutch with out reving it, it will probably stall even though it is putting out some serious power just at idle.

erika1977

ok--i'm trying to get the company on the phone right now--but according to their "graphs", there is not much differance in the 383/410 to the 383/430. yes, i want the car to launch off the line, but i really want it to CHIRP when i punch it at 40mph.--i would really love the 383/430. i also do want the thing to shake and vibrate at the line, and to my understanding, that comes from the cam, right?

Fevre

You sound like me. I want it to shake and rattle at a stand still but run smooth at 1500 rpm's. I want my cake and eat it too! That 406 does look nice! I have that web site saved on my favorites and look at it once in a while just to dream. If you go the 406 route you can go with a more streetable cam and still make those tires bark from the torque. Gitty up!

Fevre

Erika

Know any gear heads in your area? Try and track down as many people with hipo engines and see how they run. See if you can ride with them. Most will know how their cars are set up then you can decide from there. Good luck and dreaming of different engines is half the fun. :)

aj1988

From someone that grew up during the days of the muscle cars, let me say that what you are looking at is a mistake for the street. What you really should look at is a torque motor. The lower in the power band the power comes in the better. And, the lower the top number, the less wear and tear you will put on your engine. I helped a friend build a 427 that put out over 500 HP. It was blueprinted/balanced, TRW 12 1/2 : 1 pistons, L-88 open chamber heads, Hi-rise intake, 850 Holley. The secret to the engine was the cam. We called Crower Cams in Calif and gave them the specs he wanted for the street. Hydraulic, power-band of 1500 to 5700 RPM. What they sent back was one serious cam. His car was a 66 coupe with 3:36 and a wide ration 4 speed. At 70, if you put your foot all the way to the floor, the car would do a quick 360 due to loss of traction. There was no way to launch off the line without the back trying to pass the front While it was one serious hauler, he eventually rebuilt back to something that he could live with on the street. If this is a daily driver, seriously consider what you want the car to do and then find someone knowlegable to help you pick your engine.

erika1977

yeah, i live real close to rt66 drag strip, so i'm sure i can get some advice--still trying to get thru to the company--nobody answering. i'm still leaning towards the 383/430!! i don't care how smooth the ride is, i want a f#*%*ing monster!!!!!!!! :seeya

dladd74roadster

Erika, you can obtain everything you want by using an engine with less cam than either of these and there are other advantages too. I think either of the cams in these engines are a little radical. Go down on cam, eliminate the need for a stall. By coming down on the duration a little, you will typically lower the powerband you will increase your lowend torque but also at 40 when you punch it, you will still be well within the curve. But, if you are willing to buy and install the other pieces to make the 383 or 406 perform well, then go for it. Either will plaster a permenant smile on your face. :D :D

My whole point here is not to talk you out of either of these but to tell you that if you buy either, go ahead and replace the converter and invest in a gear change. With that complete package, you will have a monster. At that point, I hope you have something that gets better gas mileage or at least own stock in an oil company.

dl


[Modified by dladd74roadster, 2:38 PM 5/10/2002]

erika1977

allright, heres the scenereo--i have the differential out already (have to change the rearend cover)--i was planning on a 2500-2800 converter--now i'm not positive what gears are in the car now--i'm guessing 308 because thats what came stock on 77, but i was turning pretty high r's on the highway 3200 at 75-80mph (or somewhere around there) i have access to see my gears with the cover off and the diff. sitting on the bench. but even so, what gear would you recommend? and how much money am i looking at? remember, its not currently in the car.

dladd74roadster

Well, I can tell you that I definately have 3.08s in my car and I am in that range for 75 mph. I would suggest 3.55s or 3.70s. The gears themselves will run you about $300 plus a couple hundred (high side) for someone to set the rearend up. That includes a new clutch pack but excludes bearings if you need them. Also keep in mind that any increase in gear is going to decrease drivability on the highway. At 75 with 3.55s you will be turning 3500 and with 3.70s you will be turning about 3650.

As a side note, you can count the teeth on your existing ring and pinion gears to make sure what you have already. Just divide the # of teeth on the ring by the # of teeth on the pinion.

Hope this helps.

dl

Robert N

Just a thought to keep in mind - monsters cost more to maintain and generally don't live as long. I've personnaly believe that speed isn't everything. The car should be fast enough to smoke a ricer and show off went you want to , but be well mannered enough to drive for the sheer fun of it.

erika1977

alright, i'm gonna go count the teeth--which is the ring, and which is the pinion? :crazy: --also, what would you suggest for the motor i want? 3:55 or 3:73?--ill be back in a few with those teeth
p.s. thank you