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Hi, i'm new to the forum and have a question, i currently have an86 regal with a sbc400,w cam and intake/th400,w shift kit: but i'm still not satisfied with it's performance. I don't want a race car just a little more excitement from the pedal. what can i do to provide the best bang 4 the buck?
Cam is comp cam 12-211-2
intake- edelbrock 2101
rebuilt q-jet
Thanks for any help!
What cam, intake, and rear gear do you have? A lot of these cars had like 2.70 rear gears, guaranteed performance killers!!!! Just changing it to a 3.50 ration makes a huge difference in performance.
After the gears a set of headers will help.
A better cam. Your cam is very mild.
the intake carb and cam are all listed and i forgot to mention i already have a set of shorty headers installed(flowtech) and i'm not sure about the gears i'm sure its the stock gears that came with the car it had a v-6 in it.
the cam was recommended by the guy at the local speed shop he said it would provide the best low end power with the intake i had purchased..will a bigger cam still provide low end power?
Gears are probably the biggest thing. If you're trying to run a 2.70 rear-end ratio, you'll still feel like your lugging a tank around behind you. A 400SBC will make plenty of torque with that cam. It's the cam I'm planning to use in my 377SBC. It was also recommended to me by a professional engine builder for good low-end torque and also the biggest cam available for a stock converter.
I'd at least pull the rear cover and count the teeth to establish what ratio is there. If you're under a 3.00 ratio, it might be a good idea invest in a set of gears....maybe a posi unit if you have the budget for it.
A little off topic, but that big TH400 behind your motor is eating up some power too. They are heavy heavy heavy and eat quite a bit of power compared to some lighter duty trannies like the TH350 and 700R4. I'm not suggesting that you change the tranny out by any means because the 400 is an incredible piece of work, but that could help explain as to why your not getting the giddyup that you'd like.
If you have the stock comp. ratio I would not put a larger cam in it.Quote:
Originally Posted by sbc400Regal
Like other people have said what gear do you have?
Just a note to go along with Hopper's idea. THe THM400 has heavy internals to spin. Closer gear splits and not evenly set on the planetaries. It requires more torque to drive the unit under load. Take the gears down to a more suitable set (3.50?) and strongly consider a different tranny. Q-jet is set up for???? They can be tuned to bring this set up around big time.
With all the torque the 400 sbc makes I don't know if you would ever feel the differance but you might notice it at the track.Quote:
Originally Posted by nitrowarrior
Keep in mind this 400 sbc is swinging a 3.75 stroke the same as the 396/402.
I'll have to wait till it comes back from the shop to check the gears; but i do have a th350 laying around that i had purchased for my regal but when my mechanic found out i had a th400 also he said i should run the th400 behind my motor, you guys think it would help if i had the 350 built and installed behind my motor. and as far as the q-jet my mechanic tuned it a little when i took it back; now i'm just trying to decide on what step to make next i think it's gonna be the gears how much do they normally cost?
Fuel curves will change with gear swaps. Go forward with gears and then you can adjust and tune for your app. You might like the THM400 for your daily use. It's all a matter or perspective. Gears can be bought for as little as 100 or as high as 280. shop around. Sounds like your setup will be more than affordable. Patience is the key when setting up. There are plenty of posts on this site to show you with pics and specs to guide you to get it right. If you have doubts about set up, use a buddy, a shop or come back here and dig in with research. You will get this right with all the resources.
Assuming that your gear set is pretty high, I suggest that you consider a lower gear like a 3.73 and then change the transmission out to an overdrive such as a 700R4 or 200 4R. Lot of good info on those here: http://www.bowtieoverdrives.com/index.shtml. Whether you buy from them or not.
By making these changes you will notice a huge improvement in the seat of the pants feel you get because the OD transmissions have a much lower first gear. That combined with the lower rear end gears will give you the feel you want. Then with the Overdrive high gear, you will still have the low RPM cruise for economy and reduced strain on your motor. If you have to do one before the other, I would change the transmission first, then the gears.
They have charts on the Bowtie Overdrive page that will help you calculate what your gear ratio is based on tire diameter, speed and RPM so you won't need to pull you rear end apart to figure your geaar ratio. You will need a tach to do that.
Pat
It depends on what rear you have. I'd say $100 and up for ring & pinion. Then there's bearings, shims, seals...etc could be another $75 and up. It all depends on what you have and what you need....
You know nitrowarrior you look a lot like John Force.:LOL:Quote:
Originally Posted by nitrowarrior
I love the man, but I Don't need his daily stress....... One day we'll all sit around the campfire and I'll tell stories out of school about how he steals my kids and gives my wife a heart attack every time. That's my youngest boy back in the good ol' days.
By the way....my first avatar was not my limo, That's me. I figured if I'm gonna run around like a horse's a**, I might as well have had some more seats fo those who are always riding me to be a bit more comfortable....LOL! Denny's rendition of a big power plant wouldn't let my feet stay on the ground, Had to change it so I can steer straight.
To the OP, if I were you, I might leave the TH400 in there, change the gears and see how you feel about it then. Take 1 step at a time until you have it exactly how you want it. Many rodders try to take too many steps and either end up spending a fortune or losing interest with their project before it's finished. I know I'm guilty of it and I'm sure many of the guys on here are too.
Why don't you put some good aftermarket heads on it? That will really wake up the engine. Put some gears and stall converter also. The 400 has a 8.0 to 1 stock compression ratio with the 76cc heads. If you go to a aftermarket head with a 64cc chamber, you will raise the compression to about 9.0 to 1 which will suite the cam you have now. That alone can raise about 20 horsepower. You can expect at least a 60 horsepower gain from changing heads. Just remember to have the steam holes drilled in the heads before you use them.
I don't know if he will see 60 or more hp but a 35-40 is very easily obtained.Quote:
Originally Posted by 69elko
But like you said he could also raise his comp. ratio with the smaller combustion chamber size.
if i increase comp won't that require higher octane? but my budget really isn't ready for new heads so I'll go wit the gears first: as the rest of the build had pretty much drained the budget my car seems to constantly flatten my wallet
Like I said, take baby steps. Do things one at a time and be tedious about it. You'll save money and your budget will last longer.
Also pertaining to your talk about higher octane. Yes, higher compression might take higher octane. But you wanna go fast, you'll have to pay for it.
Fast, Cheap, Good...Pick two because you can't have all 3. Just don't pick fast and cheap. That's how people get hurt.
i appreciate the advice, i'm just learning this is my first build: i do have a question about the gears is 3.73 to tall a gear to still have good driveability as far as mpg, i don't want outrageous rpm's at highway speeds
That's all up to you to be honest. With the torque that a 400 puts out, you'd probably be good with a mid 3 like 3.42 or 3.55 or so. That'd give you a decent highway gear. 3.73 would be ok I think. I probably wouldn't go any higher than 3.73 though.
If you still have the stock pistons in the engine the aftermarket heads will work fine.Quote:
Originally Posted by sbc400Regal
You may have to use 92 octane.
i have another question about another block i have laying around how do i identify a block without the casting number? i know it's a sbc !
Besides measuring the internal works. Look at the timing chain area. 010 and 020 are an indication that it's high nickel and 4 inch bore. My brain is not in gear so I am struggling to give your more to go on. Is it still assembled? Casting marks on the end of the heads can help if they haven't been changed out. I still like going to the dial indicator for deminsions. What else can you give us? Very weird, no casting references? hhhmmmmmm
the casting numbers look like someone took a grinder to the numbers, but i will check the heads right now and it is still assembled without timing cover and oil pan>>gimmie 5 mins and i'll be done checking the heads
i got a faint impression of the block casting numbers using aluminium foil (3970014) that last number could be a 1 or a 4
That number comes up as a 70-76 350 offered in both 2 and 4 bolt apps. Could be a good one to build.
I will say that all 010 or 020 blocks are not hi-nickel blocks.Quote:
Originally Posted by nitrowarrior
The ones that I know are hi-nickel are the very early 70's 4-bolt mains found in Chevy and GMC trucks.
You're right Erik, Not all were. It is a good indication of one. I found his block numbers. I'd like for him to tear into it if he aquires it. I hope it's a virgin with possibilities.
I have always liked virgins with possibilities.Quote:
Originally Posted by nitrowarrior
Whoops I forgot this is a family show.:LOL:
Ooops!!!...LOL
thanks 4 tha help...i gotta find something 2 put it in now!