what is the MPH in the 1/8th from time slips? Heads 64cc or the 70cc version?
my mph at the 1/8 =90 mph and my heads are 6073 70 cc but im running 1094 head gasket .015 and my quench is very thight at .020
that whit exhaust close
sbc cam choice
Moderator: Team
Re: sbc cam choice
my mph at the 1/8 =90 mph and my heads are 6073 70 cc but im running 1094 head gasket .015 and my quench is very thight at .020
that whit exhaust close
buick regal 1983 357 chevrolet turbo 350 4.10 gn rear eddy rpm heads comp cam 294s 750 double pumper
11,92 @ 113.58 mph 7.59 1/8 1.59 60' street car
11,92 @ 113.58 mph 7.59 1/8 1.59 60' street car
Re: sbc cam choice
Thats what I thought the chamber volume was on yours. (89 octane).
Your cr is not as high as you claim. I bet the real chamber volume may be bigger and the piston deck clearance may be a little more. Other wise you'd be smacking the head with under .035" clearance. You best hope not.
I bet the cr is just under 10:1. Yup a little low for that cam.
You'd want to advance that cam and try it. (cylinder pressure)(100-103 in c/L)
But knowing that I would seriously first consider the blower upgade as this will get you there and BEYOND.
Easy to lower the cr on what you got, to allow the blower.
Real street performance. You won't regret the blower.
Open chambers to 75-76cc by hand ( there is lots of meat there)
maybe take another look at the porting too. (simple .400" and net peak valve lift flow test)
use a .040+.015 gasket stack
8.6:1cr.
Super low boost reliable streetable power to 11.50 ET and WAY beyond..Deep 11's high 10's in all STREET TRIM. Good investment.
If limited at the track to a 11.50 ET cause you got no roll bar in the car just turn the boost down for 11.50 ET's
(simple blower pulley swap) (with the blower you can adjust the ET of the car real easy, and you are not beating the crap out of the motor)
Other wise you get into so many changes it ends up being a "race car" and you will end up spending way more $$$ to get there. This is real good time to make this move.
I recomend you really take a look.
Note: Don't even look at the 142 blower. The 177 weiand is what you want. The price is right too.
Your cr is not as high as you claim. I bet the real chamber volume may be bigger and the piston deck clearance may be a little more. Other wise you'd be smacking the head with under .035" clearance. You best hope not.
I bet the cr is just under 10:1. Yup a little low for that cam.
You'd want to advance that cam and try it. (cylinder pressure)(100-103 in c/L)
But knowing that I would seriously first consider the blower upgade as this will get you there and BEYOND.
Easy to lower the cr on what you got, to allow the blower.
Real street performance. You won't regret the blower.
Open chambers to 75-76cc by hand ( there is lots of meat there)
maybe take another look at the porting too. (simple .400" and net peak valve lift flow test)
use a .040+.015 gasket stack
8.6:1cr.
Super low boost reliable streetable power to 11.50 ET and WAY beyond..Deep 11's high 10's in all STREET TRIM. Good investment.
If limited at the track to a 11.50 ET cause you got no roll bar in the car just turn the boost down for 11.50 ET's
(simple blower pulley swap) (with the blower you can adjust the ET of the car real easy, and you are not beating the crap out of the motor)
Other wise you get into so many changes it ends up being a "race car" and you will end up spending way more $$$ to get there. This is real good time to make this move.
I recomend you really take a look.
Note: Don't even look at the 142 blower. The 177 weiand is what you want. The price is right too.
Re: sbc cam choice
i got a new timing chaine whit 9 position should i advance my cam whit 2 or more degree
would it be good idea to shave my heads a bit
would it be good idea to shave my heads a bit
buick regal 1983 357 chevrolet turbo 350 4.10 gn rear eddy rpm heads comp cam 294s 750 double pumper
11,92 @ 113.58 mph 7.59 1/8 1.59 60' street car
11,92 @ 113.58 mph 7.59 1/8 1.59 60' street car
Re: sbc cam choice
if you order a Blower from Summit, and tell them it's to get your car to run a 11.50, they throw in a free disguise kit.
Probably want to cover your license plates too.
Maybe race only at tracks where no one knows you.
Talk with a different accent.
Avoid cameras.
Randy
Probably want to cover your license plates too.
Maybe race only at tracks where no one knows you.
Talk with a different accent.
Avoid cameras.
Randy
Re: sbc cam choice
i will run 11,50 n/a this year so randy keep youre disguise kit thank you
buick regal 1983 357 chevrolet turbo 350 4.10 gn rear eddy rpm heads comp cam 294s 750 double pumper
11,92 @ 113.58 mph 7.59 1/8 1.59 60' street car
11,92 @ 113.58 mph 7.59 1/8 1.59 60' street car
Re: sbc cam choice
If you are going to move that cam first you should degree it to see its true installed position now.
You cannot get where you are going if you don;t know where you are.
Degree it.
Then move it to a 100deg intake C/L. Do not assume the timing gear is accurate, degree it.
Then recheck vtp clearance as the intake valve will now be MUCH closer to the moving piston @ TDC.
Cause you advanced the camshaft. Do not run it like this without checking VTP clearance.
If its good button it up and run it down the track.
It will tade a good bit of bottom end torque for a bit of top end horsepower.
Make a few passes try different things. eg: colector extension, locked out timing, launch stage method, tire pressure. Get some air lift air bags for that car.
Then retard that cam by 3degrees, Now its on a 103 intake C/L.
Test again. It will eithe3r be quicker, slower or run the same.
Move the cam back 3 more degrees. Now its on a 106 intake C/L. as on the cam card.
Test it.
Now move it yet again 3 more degrees back.Now its on a 109 Intake C/L.
Test it.. WHAT is the ET and MPH change TREND?
Move the cam back to the best position.
Now you just tested 4 DIFFERENT NEW CAMS.
You can also play with the valve lash at each installed position.
Now you are testing 12 different camshaft in your motor.
Find the one that is BEST.
Your camshaft was designed for this in mind. varing valve lash and installed position.
You can vary that valve lash quite a bit.
.022" is cam card spec.
Try .014 COLD .018" COLD .022" COLD ETC .. Do not go beyond say .028" HOT.
You will find the happy spot withing these points.
Valve lash changes about .006" from COLD to HOT. Sometimes a bit more.
You really need a serious torque converter (9" 4500 stall) and 4.56 gears for that car.
Your 10" converter can be rebuilt and raise the stall speed also.
The thing is dead at 3200rpm.
Yes you could shave the heads to reduce the chamber volume to get the cr to a true 10.50:1 cr
( 92-94 octane) FIRST CC the chambers FIRST. I bet they are not 70cc.
The flat mill limit is the edge of the intake valve seat. Use common sense. Measure and calculate FIRST, Then cut the heads.
But FIRST you much check and verify the valve to piston clearance NOW. ( after you optimize the camshaft position.) The VTP clearance gets SMALLER when you shave the heads.
Do not do it blind. do not guess.
If you are not willing to measure stuff and test, leave it alone.
Take a nother look at the port job while you are there. I bet they need more work.
These heads do work well when correctly ported. Most guys don't go far enough.
Recent Yu tube video re: tunnel rams.
This one picked up a nice 50 horsepower on a 400SBC street motor.
I know my stuff. Tunnel rams make big street power. You won't get any real help here from the peanut gallery.
https://www.youtube.com/watch?v=-XjDq2DcZk0
Take a serious look at the blower, before you do all this.
But if you like tunnel rams you will love this. +50hp is not bad.
You want to run it on 92-94 octane gas. (Sunoco Petro Can Ultra 94)
Track testing and or Chassis dyno testing is how you get there, trying this stuff.
You won't get it all in one day. You got a heavy car, you got to launch it MUCH harder.
Gears, torque converter, engine torque curve., tires.
A single plane manifold can work well but will defiantly need the race converter and bigger gears.
That carb can be sweetened up and dialed in with a cool 750HP carb body kit upgrade.
You cannot get where you are going if you don;t know where you are.
Degree it.
Then move it to a 100deg intake C/L. Do not assume the timing gear is accurate, degree it.
Then recheck vtp clearance as the intake valve will now be MUCH closer to the moving piston @ TDC.
Cause you advanced the camshaft. Do not run it like this without checking VTP clearance.
If its good button it up and run it down the track.
It will tade a good bit of bottom end torque for a bit of top end horsepower.
Make a few passes try different things. eg: colector extension, locked out timing, launch stage method, tire pressure. Get some air lift air bags for that car.
Then retard that cam by 3degrees, Now its on a 103 intake C/L.
Test again. It will eithe3r be quicker, slower or run the same.
Move the cam back 3 more degrees. Now its on a 106 intake C/L. as on the cam card.
Test it.
Now move it yet again 3 more degrees back.Now its on a 109 Intake C/L.
Test it.. WHAT is the ET and MPH change TREND?
Move the cam back to the best position.
Now you just tested 4 DIFFERENT NEW CAMS.
You can also play with the valve lash at each installed position.
Now you are testing 12 different camshaft in your motor.
Find the one that is BEST.
Your camshaft was designed for this in mind. varing valve lash and installed position.
You can vary that valve lash quite a bit.
.022" is cam card spec.
Try .014 COLD .018" COLD .022" COLD ETC .. Do not go beyond say .028" HOT.
You will find the happy spot withing these points.
Valve lash changes about .006" from COLD to HOT. Sometimes a bit more.
You really need a serious torque converter (9" 4500 stall) and 4.56 gears for that car.
Your 10" converter can be rebuilt and raise the stall speed also.
The thing is dead at 3200rpm.
Yes you could shave the heads to reduce the chamber volume to get the cr to a true 10.50:1 cr
( 92-94 octane) FIRST CC the chambers FIRST. I bet they are not 70cc.
The flat mill limit is the edge of the intake valve seat. Use common sense. Measure and calculate FIRST, Then cut the heads.
But FIRST you much check and verify the valve to piston clearance NOW. ( after you optimize the camshaft position.) The VTP clearance gets SMALLER when you shave the heads.
Do not do it blind. do not guess.
If you are not willing to measure stuff and test, leave it alone.
Take a nother look at the port job while you are there. I bet they need more work.
These heads do work well when correctly ported. Most guys don't go far enough.
Recent Yu tube video re: tunnel rams.
This one picked up a nice 50 horsepower on a 400SBC street motor.
I know my stuff. Tunnel rams make big street power. You won't get any real help here from the peanut gallery.
https://www.youtube.com/watch?v=-XjDq2DcZk0
Take a serious look at the blower, before you do all this.
But if you like tunnel rams you will love this. +50hp is not bad.
You want to run it on 92-94 octane gas. (Sunoco Petro Can Ultra 94)
Track testing and or Chassis dyno testing is how you get there, trying this stuff.
You won't get it all in one day. You got a heavy car, you got to launch it MUCH harder.
Gears, torque converter, engine torque curve., tires.
A single plane manifold can work well but will defiantly need the race converter and bigger gears.
That carb can be sweetened up and dialed in with a cool 750HP carb body kit upgrade.
Re: sbc cam choice
More cubic inches are an easy way to go faster. I spun a rod bearing on my 406 when the oil pickup broke off, (no more welding for me). I ran a decent 355 for a year and eventually got it down to 12.60 using a lazy cam. I was thinking about what I would need for a better camshaft and some other improvements to go faster and realized I could rebuild the 406 for the same amount of money. With the same heads, intake, carb, exhaust, and a more suitable cam, I ran 12.50s. The bigger engine doesn't require as much rpm to make the same horsepower, it will have more torque, and getting higher compression from it is much easier and cheaper. Chances are people will not be able to distinguish it from your original motor. I got that "what the hell did you do to this thing?" question for about a month after the change.
So much to do, so little time...