[mysticmissle]

ADAM
^^^theres the perfect guy to help you. hes been there and done exactly what you are trying to do.

[BruceWilkie]

http://www.spottsperformance.com/Head%20kits everything you need for a quality head rebuild if you decide to go that route. Includes Crower springs suitable for that cam SC suggests! If you do have the heads off, a set of 1.72 Scorpion rockers would be a nice addition at this time. Spotts has good pricing on them too. (BTW American made not repackaged, with lifetime warranty too, about same price as Harland Sharps but better pieces IMO)

[andrewT]

Thank you thank you and thank you everyone. I appreciate all the help

I just found a grandville parts car with 455, th400 and 3.42 posi 10 bolt. Guy wants 1600, but I think I am going to pass for now...

I am going to stick to my original idea of just a cam for now as far as tearing into the engine. Cam, new valvespirngs, valves and maybe a new intake. headers, gears, tires, etc will all be for sure as I will need those regardless. And loud exhaust, loud and proud lol thats why I want more cam too I am friends with Adam and I had his 400 combo in mind and he just pm'ed me his setup, so I am gonna chat with him about that a bit too.

As far as weight. I am not going to buy any fiberglass parts like hood, trunk or bumpers until I repaint the car in a few years. Its wearing original laquer showing wear, but good for now. I am converting to manual steering and brakes so hopefully save some weight there. Also drag wheels will help shed some weight too. I would say I could drop a few pounds but I am into bodybuilding so...

Thanks for all the help guys! I got exams this week starting tommorow morning so I will revisit this thread once I get more time to plan this out. No rush, winter just started

[BLANK1]

I have a 68 GTO with a mostly stock 400 in it. It has a race weight close to 3800 lbs, TH-400 w/3500 converter and 3.73 geared 12 bolt. Running 275/60-15 drag radials and the suspension is mostly stock but has 90/10 front shocks and SSMachine lift bars. Motor combo is stock bottom end, #13 heads unported with factory studs and 1.52 Comp roller tip rockers, old Lazer hyd. flat tappet cam:230/230 @ .050, .490 lift and 108 LSA, Performer intake, 750 Holley vac. sec., Hooker 1 5/8 headers w/ 3" Flowmaster exhaust. Ran a best 13.08 @ 102mph at Norwalk. Might have some high 12's in it. Just running this motor until I get my 461 done.

[ponchjoe]

Andrew,

You are going down the path that I was. Screamingchief and I talked about the cam choice before. The UD cam is a good choice for the combo.

It does have screw in studs, pull the breather, you can see the pushrod guides being held down by the stud, not bolted down. 7/16 studs, poly locks, and roller rockers are a must. Degreeing the cam is necessary as well.

I cannot believe I'm hearing that you want to take the 4 spd out of the car. I'll bet you change your mind once you start driving it this spring!!!

Good luck,
Joe

[screamingchief]

Yeah,I'd at least drive it a while with the stick,ask me & I'll say they can be lots of fun to play around with.

When you start breaking stuff like the driveshaft,U-joints,or the 8.2" 3.23 peg leg rear end,then it's time to consider the swap to an auto trans and the better rear end.

Those driveline pieces will usually break long before the trans itself does.

I do recommend a good driveshaft loop regardless,I like the custom fit Metco ones myself,got one on my racecar,pretty sweet piece IMO.

Half the fun of owning a car like this is the pile of broken parts you'll end up with,they're like a merit badge of sorts,you know,to show you've BTDT and you got proof to boot!



Bret P.

[andrewT]

Originally Posted by ponchjoe

Andrew,

You are going down the path that I was. Screamingchief and I talked about the cam choice before. The UD cam is a good choice for the combo.

It does have screw in studs, pull the breather, you can see the pushrod guides being held down by the stud, not bolted down. 7/16 studs, poly locks, and roller rockers are a must. Degreeing the cam is necessary as well.

I cannot believe I'm hearing that you want to take the 4 spd out of the car. I'll bet you change your mind once you start driving it this spring!!!

Good luck,
Joe

Hey Joe,
haha I knew you would wanna reem me for it Joe. I actually want to keep the car stick (I drove it around the block for 3 hours haha, on the way to storage I opened it up HARD in farm country!). All my buddies have stick cars, but they break stuff like the plague. My Brother just broke his brand new moser axles and centre section at his first track outing, my buddy destroyed his 9 inch with a lousy 302. The M20 is not very strong, and its worth a good chunk of cash. So right now I will put an auto in since I don't have the cash to afford a good stick. As long as I am shifting I am happy, that is why the tranny is gettin a MVB. Besides I am going to be stick driving dump trucks all summer. In the future though, I will probably step it back up.

Originally Posted by screamingchief

Yeah,I'd at least drive it a while with the stick,ask me & I'll say they can be lots of fun to play around with.

When you start breaking stuff like the driveshaft,U-joints,or the 8.2" 3.23 peg leg rear end,then it's time to consider the swap to an auto trans and the better rear end.

Those driveline pieces will usually break long before the trans itself does.

I do recommend a good driveshaft loop regardless,I like the custom fit Metco ones myself,got one on my racecar,pretty sweet piece IMO.

Half the fun of owning a car like this is the pile of broken parts you'll end up with,they're like a merit badge of sorts,you know,to show you've BTDT and you got proof to boot!



Bret P.

I am going to fabricate a loop regardless. I want to change the rear end as the first thing, trans maybe later on in the summer so that I can enjoy stick driving for a while. Then put in an auto in anticipation of the bigger motor. Get the "back up" stuff covered so that it will handle the future motor. I would rather spend the money once ya know?

[cutrone]

Originally Posted by andrewT

I am converting to manual steering and brakes so hopefully save some weight there.

Cool car, (saw the pics you posted) you will love driving it once its set up like your planning ..

I LOVE my power steering and power brakes on my street strip car . Now if was a dedicated race car ...... it might worth the weight savings ????

Just saying ....

[vanmor]

I would just freshen up what you have. New rings and bearings. I'd keep the four speed and you can go up with a cam. Maybe a Summit 2802 cam and lifter kit. I'd do a little trimming on the valve shrouding on those 16s or get some 6X heads and shave them down 0.050. To save your drivetrain, don't be side stepping the clutch. Just launch easy and then floor it. You'll get the hang of it after a while.

Don't make the common mistake of building a race car for the street. Been there and it's no fun. There is always going to be someone who is faster. Let them have the headaches and you can have the fun.

I like the idea of finding a 455 auto trans for building up later. You may want to consider a stoked 400 or putting a 455 crank in a 400.

[andrewT]

I am just going to change the cam, tune the carb, get some cheap headers and maybe an intake and call it a day for this engine.

For next year I want to build a stroker, so I don't want to spend alot of money on this 400. Rather spend the money on transmission, rear end, fuel delivery, suspension, etc and do it once rather than twice.

I am debating b/w these two cams
http://www.lunatipower.com/Product.aspx?id=1742&gid=245 - the bracketmaster II
or this voodoo
http://www.lunatipower.com/Product.aspx?id=1776&gid=287

[GOAT490]

I vote for the Voodoo cam. Much quicker ramps and I like the split duration.

[BruceWilkie]

I like that VooDoo cam myself. I'd run it at 110ICL NOT the suggested 106. That will cut your dynamic compression a bit and should help out a tid in the mid to upper rpm range.

[vanmor]

I don't like either. Look for something with a 270 advertised duration. Also go with a wider LSA. Something like 112 to 114. I like 0.050 durations around 218 to 228 on the intake. 224 to 234 on the exhaust.

I'm not an expert by a long shot, but I have done extensive reading and studying on the subject. I have also talked with people who vary in age about these things over the years.

For a street driven Pontiac with a 2000 to 2500 stall or four speed, 3:55 to 3:23 gear, and 72cc to 83cc iron heads, you can't go wrong with the above cam parameters.

[andrewT]

Originally Posted by vanmor

I don't like either. Look for something with a 270 advertised duration. Also go with a wider LSA. Something like 112 to 114. I like 0.050 durations around 218 to 228 on the intake. 224 to 234 on the exhaust.

I'm not an expert by a long shot, but I have done extensive reading and studying on the subject. I have also talked with people who vary in age about these things over the years.

For a street driven Pontiac with a 2000 to 2500 stall or four speed, 3:55 to 3:23 gear, and 72cc to 83cc iron heads, you can't go wrong with the above cam parameters.

car will be getting 3.90 gears, turbo 400 with 3000-3500 stall.

honestly I don't know much about cams and how they work. Like above when GOAT490 said "fast ramps", I have no clue what that means. I am guessing it means the valves will be opening and closing faster

[BruceWilkie]

Originally Posted by vanmor

I don't like either. Look for something with a 270 advertised duration. Also go with a wider LSA. Something like 112 to 114. I like 0.050 durations around 218 to 228 on the intake. 224 to 234 on the exhaust.

I'm not an expert by a long shot, but I have done extensive reading and studying on the subject. I have also talked with people who vary in age about these things over the years.

For a street driven Pontiac with a 2000 to 2500 stall or four speed, 3:55 to 3:23 gear, and 72cc to 83cc iron heads, you can't go wrong with the above cam parameters.

Look at the timing specs will ya!

http://www.lunatipower.com/Product.aspx?id=1776&gid=287

If he Ran a Summit 2802 which is roughly what you describe which has 114 LSA installs at 110icl iirc, the intake closing will be about the same spot as it would end up with my suggestion. In other words the number of degrees in compression would be quite similar!
The exhaust opening point would still be in a favorable position plus this cam would have less overlap/overlap window.(his combo isnt going to benefit any from more overlap!)

The 2802's best quality is its intake closing point helps where compression is on the edge for pump gas. Its certainly not a better cam than this VooDoo for his application.

BTW, next time you get a chance, degree a cam with the heads off and pay close attention to where the piston is. Not just the degree wheel, but where the piston is relative to the deck, relative to cam timing! Find seat time and other points like .020" and .050" and .100", .200" etc. cam lift.

You should discover that LSA and duration at .050" is NOT how a cam is designed nor how it should be chose! Likewise you dont "automatically" decide 112 LSA needs to be at 108ICL! LSA and ICL are coincidental centerlines of chosen timing events!!! Best used for checking purposes! Likewise duration at .050" tells you little without a whole bunch more info! Again best used for checking purposes.

Cam timing events and ramp rate requirements are based on application. Head thru-flow and stroke greatly determine what cam timings and ramp rates will be required for the result intended.

btw If you want to get a better perspective than my above suggestion, check timing points at the valves on #1 with the head off the other bank where you can observe that #6 Piston wiil be at same position in the bore as #1. This way you can see actual valve movement and all the relationships to what I said above. Even more interesting is to do this with a 350or 400 then put the same cam in a 455 and repeat the process. Keep in mind either engine hits max piston speed NEAR approx 75 deg bbdc.(each will be different fwiw) I'll let you do a little research as to why that is important to know.

[BruceWilkie]

Andrew it looks like a good pick to me. Your compression is likely to be a slight concern and thats mainly why I suggested the deviation from "box spec" ICL timing as it will give slightly less cranking pressure and move the powerband up a tid. Your convertor is more than enough for this cam. (Plus it will compliment the cam for launch and after the shift recovery.) With your gearing it shouldnt flare much at all under light load easy driving conditions.