Just curious if anyone is running a nice 377 motor, where they got it from, and if they were pleased with it.

I've built one before. It wasn't mine. I suppose it was "nice". I don't know exactly what heads ended up on it. Seems like he had an old factory replica solid cam (754 cam I think, can't recall for sure, it was about 20 years ago) so it probably had good top end.

I built it. I don't buy stuff like that, that I can do myself.

I was pleased; I got paid. The customer seemed pleased; he said it ran pretty good, stronger than a typical 350. I'm sure it ran just about like a 350 that had been bored .125", can't see how it would really be any different from that.

I was bummed that he wanted to downgrade a perfectly good 400 block. Didn't make sense to me. But.... he paid the bill, and it was his stuff, so I guess he could do what he wanted with it.

Would I do it for myself? No. Not no, but rather hell no.

The son of the guy who is putting my 396 heads back together (after I get done with porting them) has a friend with a 377 in his '70 Chevelle that we all race with. It was built right and all, but it really isn't any faster in the 1320 than similar streetable 350s.

Those old Grand Sport Corvettes ('63 i think) had some really sweet 377s... i saw something on tv about them. The ones they raced on the long tracks would wind up to around 8500 rpms. Nice motors...

I have one. Its a 2 bolt 400, with spayed caps, eagle steel crank, eagle rods, 13.5:1 domed pistons, Brodix 11x heads and a big nasty 700 lift solid roller.

A 377 is in the same boat as a 327. For your normal car, they are not the best choice. If you have a light car, our in my case truck. They are perfect. Instead of monter torque off the line and either breaking parts or blowing off tires, you get your pull on the long end. The motor puts out over 600HP at 8600 rpm's.

I'd rather have like say 370 ft. lbs of torque to get me going and 480 up top to scream by.

So get a cam and heads to do that. Any motor can be built to rev if it is built and balanced right. You are just robbing yourself of cubic inches and in turn power. Just think that is 27 ci you are getting rid of.

Ben

Cubic inch is only part of the puzzle, think of where your powerband is needed. The shorter stroke is nice when you bracket race. You tend to put more mph on the long end then other cars. That faster closing rate makes it harder for the oppenent to judge his finish.

My street/race car is a 383 and my full race car is a 377. Both engines are awesome. Could I have built it as a 406, yes, BUT I also could have built up to a 500 sbc. With the high flowing heads I have, the 377 fit the bill for me.

There are other benefits of a high winding 377, such as highway performance. A 406 would be nice, but frankly I don't want to have to spend another thousand or so reinforcing every component in my drivetrain to accomodate a monstrous amount of low torque. Besides a 377 with 450 ft. lbs is making more than enough torque to launch the car incredibly hard, a comprable amount of up top HP for this 377 I have found has a new LS6-like powerband and it pulls from 2500-6500 rpm. I'm not asking for your opinions on the 377 if you don't have one, I am asking those who have them to tell me what it did for them. It's all in the setup really.

In that case could you explain why there would be better highway performance with the 377 compared to a 400 or 406 that was built for the same RPM range?

Also, if you are planning on even the 377 I would reinforce drivetrain parts. Just because you built the motor for high end doesnt mean that it will not break parts. If you built a motor for higher rpms you just lauch at higher rpms, or run a higher stall which will still give you quite a shock to the drivetrain(especially if its a manual).

I think about it this way. Since you can build the 400 to rev the same and still have a bit more lowend(wider powerband as a result of more cubes) then "I" would have no reason to build a motor that makes the same or less high end, but less low end. If you figure that ever .1 sec less you get rid of on the low end is 1.5-2 in the quarter then I dont see a benifit of the 377 other than being cheap with the driveline parts that I wouldnt feel comfortable leaving behind a 377 either.

Maybe you have other reasons and I would love to hear them but I myself dont see any viable reason to throw cubic inches out the window. The only reason that I might see is the ability to run longer rods and hense being able to run higher compression without detonation.

Out of curiosity, is this going to be a street/strip vehicle or track only?

Ben

I have a 383 in my 69 camaro and I've put 4 differant cams in it and never seems to rev any higher. (could be heads are maxed). If I were to put another engine together I would do a 377. Getting a 400 to rev takes major heads and valvetrain not to mention you have larger crank journals which add weight and friction. Anyone who follows NASCAR engine building closely will see that with better metallurgy (sic?) journal size has become smaller yet. Friction is heat and heat is wasted power. A 377 can have long rods with the shorter stroke and lighter crank has slower piston speeds and less parasitic drag. It does come down to applicaton though. If you go mild, a 400 gives you best bang for the buck. If you run a manual and low gears a long rod 350 or 377 is more fun.
just remember 400 blocks have siamessed bores and run hotter. I've built each engine and all have there best applicatons, it ends up being what your doing with it.

i'm in process of biulding a 377 right now. all i have so far is a bowtie block but it will have a forged scat rotating assembly with afr heads untill i can afford my areo 32 valve heads. hopefully when it's done it should run with the best of them

Momar, I know a guy running a 377 powered Nova and he is runnin high 9s all motor, mid 8s on spray and he's street legal (off the spray obviously). If anyone can tell me that this is poor performance, I'd like to see what they run with their 383 or 406. Sacrificing cubes doesn't mean sacrificing performance, I really would hope that in this day and age we're past that mentality, especially since GM has put out a 350 than makes big block power and is powering a car faster than 90% of big block factory cars from the smog era in the 60s. LS6 Z06, and it's clean and gets excellent fuel economy, which a smaller engine tends to be hence making it easier to pass emissions. and when you're mill is making 470 ft. lbs or torque, you're not short on it by any means. That is why I want a 377 instead of a 406 or a 383. I don't want 500+ ft. lbs of torque cause I don't want to have to buy 18" wheels, get and 315+ tires just to attempt to hook. I want an engine that gives LS6 type response and is rev happy and can handle a high way punch as well as run from a dig and not be traction limited, a 377 is what fits the bill.

Can we have some specs on this "street legal" motor?

Ok, don't you think that 40 years of research and advances in technology could have had a little to do with that? You think that GM can't make more power with a big block today than a 350?

I want to know the specs for the engine you plan on building. You want a motor that revs and still makes 470 lb/ft of torque? How much money do you plan on putting into this thing?

Lastly, from the way you describe it, you want a motor for the street that can rev 8000 rpms and you don't want to replace any other part of your drive train and make it grab without putting huge tires on it. Hmmm, let me check with the people that live in a Utopia..........ok, they say it's not possible. Sorry.

What kind of specs do you need on my friends Nova? It's about a 700 HP motor. You need specs because you are ignorant and don't see how a high revving small block can run 9s? His Nova is pre-emissions and he's running a race cam and he's got a 12 bolt with 4.56 gears and a built TH350, he's also got a 200 shot of crack to send him into the 8s at the track. I never said it was a tame street car, but as far as DOT is concerned it's streetable and thats all that matters. and let's see, GM already has made fuel injected big blocks, they are in trucks, they hardly make comprable power to the LS1 and LS6, and they barely pass emissions, in fact if they were in a car and not a truck, they wouldn't. GM also makes a fuel injected big block crate motor, it's called the Ram Jet 502, it has 150 more cubes than a LS6, makes only 100 more HP and ft. lbs of torque, probably weighs a good 200 lbs more and it isn't emissions legal in any state that has pollution controls, and will not get you any decent kind of fuel economy, so when GM does make a big block that gets decent fuel economy and makes over 405 HP and passes emissions, let me know, until then shut up. the engine I'm building operates in the 2500-6500 rpm range, it's gonna be a solid roller motor with high lift cam, fuel economy will be mediocre, but it'll be better than a 406. And fools stop putting words in my mouth, I don't think anyone running a 9 bolt would need to replace their rear end even up through 500 ft. lbs of torque, but I'd really like to run a 4th gen driveshaft. As for my transmission it is already replaced with one capable of handling over 600 ft. lbs, so a 377 wouldn't be a problem at all, a 406 that can provide a similar HP output would be dumping a lot of torque cause of the longer stroke. Doesn't take a genius to figure that out. And I never said I wanted 8000 RPMs, I said I wanted an LS6 style power band, that is 2500-6500 rpm so shut up and stop putting words in my mouth. 285s would be proivde plenty of grip for the motor I'm gonna build. And as far as money goes, the total cost is gonna be about $6000-7000 dollars. There are plenty of engines operating in that range on the street, but I want a lot of top end to go with decent low end. 377s are top end motors. I don't need to here this "why not get a 406" crap. I don't want a 406 cause its not a top end motor, it is quite common, and the only reason to do that is if I wanted to roast the tires off my car every stop light. If you haven't run a 377 or don't know anyone who runs a 377 please stop telling me a load of BS like "get a 383 or 406" or even question my reasons for going with a 377. Also if you've never been in a car with a mightly top end, go hop in a Z06 or a modded Supra and you'll understand my desire for the top end.

It's time for you to take a breather, buddy.

You're trying to win arguments by spinning truths.

1) You made an example out of your friends Nova. It is pre-emissions, is yours? We are on a third gen board, so I'm assuming no. Therefore, you can't legally have the setup he has.

2) GM builds TRUCK big blocks. They also build TRUCK small blocks. However, you insist on comparing the Truck big blocks to the Car small blocks. They have different applications. Also, a big block, like you said, is much harder to keep emissions legal. Therefore, it isn't even coming close to it's power potential.

3) I bet I could build you a 377 motor that didn't act like a top end motor. On the same token, I bet I could build a 400 that did act like a top end motor. It's all in the setup, just like you said.

Now, if you want a top end motor, that's fine, you can make any motor into a top end motor. I think you just want a stroker to be different. I'm not condemning you for it, I have a 383. But don't be trying to label it any way other than that.

I'm not trying to argue, I merely asked who has a 377 in their 3rd gen and what does it run but some people instead of giving me a straight up answer try to make an arguement of it. I didn't ask for a bunch of crap like momar was spewing about sacrificing cubes blah blah blah, I didn't ask "hey, what do you all think of 377s" I just asked who had em and what do they run. I initially wanted a 383, but for what I wanted to do a 383 wouldn't have done it for me. I've got a build up in mind, it's for a 500 HP/470 ft. lbs 377, and it's what I want. A friend who has a 10-second LS1 trans-am recommended it to me and suggested the parts for the build up and he introduced me to the guy with the 9 second (8s on juice) 377 powered nova. obviously it's not gonna be the setup I want or am gonna build, his is more or less a race setup in a pre-emissions car but it doesn't mean a 500 HP motor with a streetable cam and emissions legal heads and exhaust won't pass. I'm gonna try and see if I can hook my smog pump up to the motor, my only problem is finding an EGR equipped FI unit than can operate up through 6500 rpm. And yes, there are 377s that aren't high end motors, goautocenter.com sells two of them, 315 and 340 HP respectively and all below 5500 rpm, that setup doesn't interest me. And yes, I also like the fact that a 377 isn't too common in many cars.

I am very happy with a 377 and would built another one in aheart beat. I weighted the options when I styarted this project. Yes, I could have built a 383, 406 or a 427 small block. The motors are great, but they throw around a lot of weight. It is not easy to have them spin way up and still make safe power. It can be done, but it costs. Same goes for a big block. Most are never turned up more than 7 grand. Too much strain. Can it be done, yes.

The checy 302 is a popular motor and it has the same manors. Down low, its tame, but upstairs, they were monsters.

Each motor has its own place in its own application.

Now, to answer the original post, if you have a 3rd gen the is a street/strip car, a 377 may not be for you. Like the 302/327 you would have to run really deep rear gears to get it out of the hole. In that case, more cubic inches would help. Weigh you car and talk to your engine builder or machine shop before you commit to a path.

By the way, I have always wanted a blown or TT 377. I think that would be the best of both worlds!

Ok, you keep talking about a streetable motor and then a large sollid lifter cam. These 2 do not totally go together, but then you say that you want your powerband to be up to about 6500. 6500 is in no way shape or form to much RPM for a properly built 400 or 383. The one thing that really gets me is that you talk about being past the day and age that you cant make power with less ci. Well technology has advanced. I will give you that, but in this day and age you speak of we also can build longer stroke motors to rev higher without costing ungodly amounts.

Also, you speak of passing emissions. That could be a slight problem with a high reving, high lift, solid roller cam. Also, the only real choice for you as far as a fuel injection system goes that will allow you to rev to around 6500 and have egr is the Super Ram. Also, I your fuel economy might be better than a high reving 406, but if you ran a smaller cam in the 406 you could make the same amount of power and quite possibly get better gas mileage.

Next, you keep throwing out 470 ft lbs of torqe? Have you seen someone do the buildup you want? If so what RPM did it make that torque at. It is not so much how much torque it makes as where it makes it it. You are going to need steep rear end gears and a high stall. (what rear gears do you have in that 9 bolt anyway because they are not exactly cheap to replace).

I am attatching a picture of a couple desktop dyno files. The one with just the straight line is a 400 w peak power at 6500 w/ roller cam, AFR190 heads, single plane intake, 800 cfm carb ect... The one that has the dots on the line is a 377 (3.48 stroke and bored over .30. I didnt change anything else. They have the same peak power rpm and the 377 only makes 2 more hp but 18 less ft lbs. You may say that you were wanting to shed ft lbs but the peak torque is still at the same rpm. Also, the 377 doesnt loose hp as fast but you will notice that they are both about the same until well after peak power so it doesnt matter.

Ha, I think I just realized where you have been getting your power specs for the motor you want to build. You have been using desktop dyno havent you becase that is pretty close to what I cam up with. If that is the case, I would also just suggest using it as a tool to help figure power curves and such because your power wont really be what it says.

Ben

This is what I was planning. I was figuring I could use the rev limiter on an MSD 6AL ignition box and set it at 4800 or so to make sure emissions is passed if I had my doubts. Do mini-rams come with EGR??? Also S&P makes a few nice FI units (Ram Port is one capable of hitting over 6500) but I am waiting to hear from them about EGR, in their catalog they have an option that says "Emissions" and its $50 more... I'm assuming thats for an EGR baseplate. I didn't use desktop dyno actually, my boy with the 10 second LS1 gave me the numbers with a projected output. AFR 195s, 377 block, a stealth ram intake, all accesories cept A/C, Comp Cams 280AR mechanical roller, 1.5:1 roller rockers, SLP 1 3/4, Headers 3" catback, and a high flow cat converter. He said it'd make over 500 Horses easy and would be a screamer. I trust him since he built his TA and knows his ****.

Nope, no egr on the miniram. I guess there might be other emissions legal fi systems out there, but out of the ones that will work on the tpi computer I know that the Super Ram. Neither the Miniram or the Stealth Ram have EGR, and you have to eliminate EGR to use a modified LT1 intake because the distributer is in the way.

Ben

Oh, and where do you live and how bad are your smog checks? I dont thing a rev limiter will help. The reason I mentioned it being a possible problem is because larger cams cause you to produce more polution down in your driving range. I dont have to deal with emissions so I am lucky, but depending on how strict your emissions are you may have a real tough time passing with a motor like that.

Ben

I'd say the smog laws aren't half as bad as california, pretty much as long as they fall within the bracket of '89 emissions standards for a 350 it'll pass. My friend with the 10 second t/a passed last year, he should again. Superrams go for pretty cheap on ebay, they reuse stock fuel rails don't they? The Ram Jet 350s are emissions legal aren't they?

I dont know about the fuel rails. I thought that you had to use specific ones, but I could be wrong.

Also dont know if the ramjet is smog legal or not. Since I dont have to worry about smog, I never really had to search to hard. I always figured if I used something it would be a LT1 intake or a miniram but neither are smog legal. I am getting a complete LT1 now so I know what I am using now anyway.

Ben

I supposed you could use an LT1 intake with an Electromotive unit, those no need to drill a hole for the distributor since ignition is magnetically controlled and uses a standalone computer, but those units run from 600-1200 dollars as it stands, probably cheaper just to go with a super ram. Ebay never runs short of people sellin their super ram, don't need the standalone, just a $500 super ram and $860 Holley DFI that'd be quite nice

Well, I am using a complete LT1 myself, computer, block, heads, intake and all. I got it for 600. What I meant by LT1 intake though is you can modify them to work with a distributer. Unfortunately this wouldnt help you though because the distributer is in the way of where the EGR would be. Just in case you wanted to see go to www.lt1intake.com

Ben

I know I've been there. I'm saying EGR would be in place if you didn't have to drill a hole for the distributor if you were using an Electromotive DIS unit.

I see.

I don't think I'd be ready to pay $800 for it. Although because it uses a flying crank trigger, it's the most efficient and precise timing.

you would have to drill a hole for a distributor but instead of a distributor you can just put a plug in there. the reason you need that plug in there is to run your oil pump

You might not have to drill a hole. You might be able to rig something up like the LT1's have. They have a shaft that mounts in the lifter valley and goes into the distributer hole in the block and connects the cam and the oil pump shaft.

Ben

rigging something up would be way more expensive if you include the cost of the shaft, mounting, gear, and machining. compared to the cost of a $60-80 adapter shaft.

I've got a 400 SBC in my car right now. I constantly break transmission and motor mounts because of the low end torque. I was seriously considering destroking it to a 377, but after some research, I've decided to just keep it a 400. Of course its fun to shift gears at 8500 rpm, but it would be awfully slow in a 3500 pound car. My friend's 98 cobra has this problem, it has nothing off the line. Most people with fast Cobras are running 4.10 or higher rear gears, just to get off the line fast. In my opinion, for a street car, off-the-line torque is much better than top end power. You'd be surprised how hard I can launch my car on street tires, just because of the torque. I estimate my car's current horsepower around 200, but the torque should be around 300. I need some better heads and a cam, though, so I can match that low end torque with more top end power, because right now, it falls flat on its face above 3500 rpm.

Supras are heavier cars with decent off theline torque but nothing special. It's not gonna launch intensely hard, albeit a supra with 300 ft. lbs of torque will launch as hard as a camaro with the same amount, but the top end on those cars is unreal. I've got a buddy with a Supra, you'd think you're gonna beat him cause you put 3 cars on him when he you jump off the line but then his turbo spools, his top end is like 450 HP, and he flies by to a high 11 second 1/4 mile. And this was against an LS1 Vette I was driving.

Turbocharged cars are totally different though.

Oh, and Ward, have you tried using poly mounts so you dont have to keep replacing them?

Ben

How so? They hit their powerband when the turbo spools, they don't have much until it does. If anything a V8 would be better cause you'll always have low end torque due to displacement.

I'm confused. We can usually apply the same common logic to upgrading the cubic inches to a motor. Now all the "old timers" say not to bother with a 327 because a 350 will make more power. True. No argument there. Now I'm wondering how a 377 will make less power than a similar 350. We're all using the same logic here, right? Now I can't say for sure how a 377 performs because I think going through the effort of destroking the 400 isn't worth it, so I've never had my hands on one of these engines or been able to hook it up on a quick dyno run.

So I guess my question is: how can subtracting 27 cubic inches from a 350 reduce power and adding 27 cubic inches reduce power also?

depends on the setup. There are 377s that only make a bit over 300 HP and aren't very high revving. Personally that's a waste and defeats the purpose of a 377, which can be a high revving powerhouse. An AFR'd, super ram'd, DFI'd solid roller 377 can be a 500 RWHP beast and redline at 7 grand, and that's what I hope to build. Hell, if it's only 450 RWHP but revs to 6500 I'll be happy, it might not be able to be done for cheaper than you could build a 350 to 450 RWHP, but oh well. I'm hoping for 500 RWHP and with my buddy who's build his LS1 into the low 10s helping me I think we'll be doing it. If I'm in the 11s by July I'll be content! 377 = 6.2L btw, so any truck with a 6.2L V8 has a 377. goautocenter builds a 377, but for what they want for their 340 HP one, I could have my longblock assembled with a forged crank, comp cams solid roller setup, and AFR heads. But mod for mod a 377 should make more power and torque than a 350 cause of its displacement.

I just dont think that that is the case. I have a turbo thunderbird, and yes, it does lack a bit under 2500, but It seems to accelerate pretty good from around 2500-6000. That is a pretty wide powerband if you ask me.

As far as a V8 always having good lowend that is not true. If you listen to these people that have experiene with them they have been telling you that a high reving car is a dog down low. You will need steep gears and either a manual or high stall to launch good.

Ben

May not be the motor. His car may be still setup with gears that do not suit the motors powerband. If the gears are not deep enough, it would hurt et.

I think a 3000 stall is plenty. since when was 2000-6500 rpm considered unstreetable and a dog??? Lots of cars operate in that powerband btw including the LS1 and LS6-power cars, albeit the LS1 cuts out a 5500!

Cutting out at 5500 and redlining at 6500 are a lot different. Also, just because you can build a motor that will operate within certian rpms doesnt mean it will perform well in all of them. Also, I am not saying that the car will be a dog totally. Just that if you dont get gears and stall to match you may be dissapointed.

Do you already have a 3000 stall then? You will probably also want some 4.10 gears for the rear. I do think that a 3000 stall will do pretty good if that is what you have, but just for reference, I have been on the LT1 board at camaroz28.com quite a bit lately and it seems that the people that are running that big of cams are using around 3500 stalls. There may be some using 3000 but you dont see to many run much lower than that with that big of a cam.

Ben

Say I wanted the same top end power characteristics zerotosixtyV8 wants (Z06 Style), but instead of using a 377 N/A, I want to use a 350 with a blower. What kind of mods or combos would you sudgest be done to the 350 to make more top end power? I dont really want to rev more than 6500 rpm because I dont trust anything higher than that. The blower is a Vortech S-Trim (V1) and the motor is a L98. I already have planned a Holley StealthRam, a 749 ECM swap and I'll be burning custom chips (multiple chips from 9psi to 18 psi). I havent really researched what I should do with the motor itself (heads and cam, etc) to make alot of top end power. Right now with the TPI setup (stock L98 and blower @ 6 psi) it falls on its face after 4500 rpm. Drivetrain will be a T56 and a stock 10 bolt with upgraded gearing. Car wont be used for dragracing, so wont have to worry about hard launching. I want to build this one to have some top end fun (other Camaro will be the torque lover). After riding in my friends Z06 I'm sold on the top end street car type of buildup. Curious what you would sudgest. Thanks!!

momar?
Decatur eh?
what you drive you don't have a 3rd gen do you?

Have you seen the plates on the turbo coupe? lol. If that what you are referring to, yes, its mine. If you havent seen it then uh, no, I would never drive a f*rd.

Actually though, I am driving a turbocoupe around right now because it was what was available. I have a blue 1985 Trans Am also. The 305 took a crap a little over a year ago and I have been upgrading the car ever since. The car was stock when I bought it other than a custom mufflerless exhaust that was still 2.25" and non mandrel bent. I just got it running recently. I need to get the instrument cluster wired up still because I am in the process of converting to an electric speedo, and my vss wont work until I do. Without the vss there is no lockup, and that is not good for the tranny. Well, I have a couple sound clips in the sig from when I first got it running. Here are some pics. www.picturetrail.com/momar01

What do you drive by the way? I may have seen you around town. Whats your name?

Ben

Oh, and that pic I posted was my senior pic. I had just waxed the car and the paint hadnt started to peel on the hood yet. It could really use a paint job but I dont have the money.

Ben

you street race
I have a Mustang you could race for some money!

I got a 81 Firebird
w/stuff

You have a mustang as in it is yours, or as in you know someone. Also is it around town a lot? What does it look like?

Ben

not mine a buddies
black 93 lx

my 81 bird is getting project Black Cell done at the moment

so?

or I have a friend in a 98 Z that will race ya bone stock