421 swap pics within
#1
421 swap pics within
Well finally bite the bullet. After many years of owning this car and numerous na and fi combos I finally got what I wanted. I always wanted a 406 but after geting with a builder that knows his stuff and is a well known stroker motor builder on corvette forum we decided on a 421. Jim421vette is a well known corvette forum member who has built literly hundreds of stroker combos. To say he has experience and expertise in this area is an understatement. We hit it off well and talk on a regular basis. As motorheads this stuff never gets old no matter how many times you see it or build it. Here is the rundown:
Dart shp block
Dragon slayer 3.875 stroke crank
Crower stroker rods 6.0
Ati super damper
Ross pistons flat tops -5 cc reliefs
Crane cam 242/248 .598/598 hydralic roller( 1.6 ratio) could change as we are running a shaft system
Crower ss shaft system
AFR235 comp ported heads
Miniram with monoblade
11.1 comp
Canton rr pan
Here are some links to build:
Right now we are all set with the long block. Basically this is a max effort hydralic roller cam motor. I know im leaving alot of power on the table not going with solid but its a street strip car. Looking for at least 550 to crank. Will be running a small nos shot most likly 125-150 hit. Will make a nice runner. Will update as more pics come in. Take care and thank you for checking in.
Dart shp block
Dragon slayer 3.875 stroke crank
Crower stroker rods 6.0
Ati super damper
Ross pistons flat tops -5 cc reliefs
Crane cam 242/248 .598/598 hydralic roller( 1.6 ratio) could change as we are running a shaft system
Crower ss shaft system
AFR235 comp ported heads
Miniram with monoblade
11.1 comp
Canton rr pan
Here are some links to build:
Right now we are all set with the long block. Basically this is a max effort hydralic roller cam motor. I know im leaving alot of power on the table not going with solid but its a street strip car. Looking for at least 550 to crank. Will be running a small nos shot most likly 125-150 hit. Will make a nice runner. Will update as more pics come in. Take care and thank you for checking in.
Last edited by IROCZ1989; 05-19-2013 at 07:07 PM.
#7
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Re: 421 swap pics within
Subscribed.
Max effort hyd roller? Naw lol you could easily go up another 10 deg of duration and more, and lift in the .640-.700 range with a different lobe and or 1.7 rocker and still be very driveable with well tuned valvetrain and morel hyd roller lifters i run 246/252 .640 on my 400 turbo motor and its plenty streetable.
But what you have now is going to run very hard, just would love to see more lift atleast with that duration, for the given cubes and heads. That beast will want to breathe above 6000 rpm and Jim definately understands that. I have read a bunch of builds on corvetteforum lol
Max effort hyd roller? Naw lol you could easily go up another 10 deg of duration and more, and lift in the .640-.700 range with a different lobe and or 1.7 rocker and still be very driveable with well tuned valvetrain and morel hyd roller lifters i run 246/252 .640 on my 400 turbo motor and its plenty streetable.
But what you have now is going to run very hard, just would love to see more lift atleast with that duration, for the given cubes and heads. That beast will want to breathe above 6000 rpm and Jim definately understands that. I have read a bunch of builds on corvetteforum lol
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#8
Re: 421 swap pics within
Well I should be more accurate and say street/strip max effort. Dont want to run too much of a stall and want my power brakes to work. With the 235s we came to the conclusion that with the bigger 2.125 intake coupled with the better flow on the intake at lower lift numbers and flow in the exhaust lift points over the 220s we feel 6500 max rpm will balance longevity and power. Dont feel the bigger head will hurt low end torque that much. We could have even went with the 245s, these motors will make 400+ ftlbs in the low rpms easily. My springs are rated for .650 max lift but are the smaller dia 2019s. Titanium retainers and lightweight 8mm valves. I think we may go with a 1.65 witch will yeild a .613 max lift. 1.7 is .632. He mostly uses the 236/242 comp grind which will run to 6300 in his previous combos. So well see how this goes. I really have no other engines to compare to because most just run a solid roller with these motors. Will keep this updated as It goes. Take care
Last edited by IROCZ1989; 06-05-2013 at 08:10 AM.
#9
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Re: 421 swap pics within
Sounds like a good plan. It will be very streetable. I run 245's on my car and there is no problem moving around thats for sure. Now turbo car is a different animal off boost but general driving around its not much different. You will be all done by 6500 thats for sure and definately a good rpm range for street strip. Those heads move air, and good springs that i would consider shimming slightly for a tad bit more seat pressure, 160-165 lbs for better control with the big 2.125 valves. Still have enough room for .613 lift. I turned 7k with a 230 deg .613 lobe with afr 8019 springs without titanium retainers but 2.050" valve. 165-170 lbs seat, about a 1.775-1.78" install height
#11
Re: 421 swap pics within
We actually had a AFR shim them to either 160 or 168 cant remember. Here are some new pics just got from Jim:
Billet chain is nice with a enclosed torrington bearing. Unlike the older open designs. Cam was installed and degreed and we found out it was 1° retarded. On the other new cast street chain it was 3° advanced. So we left it as is. Got a great price on these AFRs so anyone wanted a set, best prices anywhere pm me for info. Take care all.
Billet chain is nice with a enclosed torrington bearing. Unlike the older open designs. Cam was installed and degreed and we found out it was 1° retarded. On the other new cast street chain it was 3° advanced. So we left it as is. Got a great price on these AFRs so anyone wanted a set, best prices anywhere pm me for info. Take care all.
Last edited by IROCZ1989; 06-05-2013 at 08:07 AM.
#13
Re: 421 swap pics within
Hey Guys, I thought I would chime in. I haven't been over here in a while. Darren, I think this combo will work well and do everything you want it to do. I think most the engines I build are in the 221-236 intake duration range. And they pretty much all run on pump gas. I have done a few big inch SBC's that are in the 240+ duration range, but usually when you start getting that big, I usually just recommend going solid roller. But I understand that it's nice not to have to pull off the valve covers. I think this should easily make well over 550hp. 421's are one of my favorite engines to build. They make alot of torque, but can still turn some rpm. Also, Darren your spider tray showed up, so there are a few more parts that I can put on it. Take care Guys, I will keep everybody posted.
#14
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Re: 421 swap pics within
Yeah big motors with big valved heads that want to turn some rpm with aggressive lobes for power need some strong springs and you start pushing limits on what hyd roller lifters can handle. Morels are suppose to be strong enough to handle mild solid roller springs. Not familiar with the others. Ls7's tho have handled 160-180 lb seat pressures too which can handle most cams. Solid would be best for power but street reliability and maintenance arent as good as hyd rollers. This build should easily exceed 550. I have seen lesser motors make that power. This has some good parts.
#15
Re: 421 swap pics within
Not much of an update. Going to Mello Yello NHRA nationals in Epping this weekend. Staying over sat till sun to see the finals. Little r&r for a gear head. Next step is miniram is going to be sent to porter to be flowed and ported to see before and after numbers. Best thing I can say to anyone contemplating a new build, go as big as you can, 400+ all day long. You just cant beat cubic inches. With nos or fi on a big cube motor youll never second guess your combo. Take care all...
#16
Re: 421 swap pics within
Little update. Me and Jim went over the combo amd decided on 1.65 on the intake amd 1.6 on the exhaust. Giving the engine a .613 intake lift and a .598 exhaust. This is with a 244/ 246 duration ona 112 lobe on a billet cut crane cam. We went with the crower stainless steel shaft system . Some may say overkill. But since we are starting from scratch cost is negligable. Just an overall it is a more solid stout valvetrain and better than using offset rockers, geometry is improved. Will post pics when it comes in end of this week
Btw Mello Yello nationals were unbelievable. For any gearhead its an event not to be missed. Cant exlain the experience of being there and watching two 8000hp Top fuels line up and run. Just plain insane...
Btw Mello Yello nationals were unbelievable. For any gearhead its an event not to be missed. Cant exlain the experience of being there and watching two 8000hp Top fuels line up and run. Just plain insane...
#18
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Re: 421 swap pics within
Little update. Me and Jim went over the combo amd decided on 1.65 on the intake amd 1.6 on the exhaust. Giving the engine a .613 intake lift and a .598 exhaust. This is with a 244/ 246 duration ona 112 lobe on a billet cut crane cam. We went with the crower stainless steel shaft system . Some may say overkill. But since we are starting from scratch cost is negligable. Just an overall it is a more solid stout valvetrain and better than using offset rockers, geometry is improved. Will post pics when it comes in end of this week
Btw Mello Yello nationals were unbelievable. For any gearhead its an event not to be missed. Cant exlain the experience of being there and watching two 8000hp Top fuels line up and run. Just plain insane...
Btw Mello Yello nationals were unbelievable. For any gearhead its an event not to be missed. Cant exlain the experience of being there and watching two 8000hp Top fuels line up and run. Just plain insane...
Good idea on 1.65 rockers intake side. Feed that beast, thats alot of cubes and the heads flow good up high so use them
#19
Re: 421 swap pics within
Orr, me and Jim went over it quite a bit and he had offset rockers like you on his 450 and ran into the same issues. Just couldnt get it right. Cam was a big decision, glad comp screwed up a custom grind and they made us eat it so we went with a crane unit.
Not much in updates, just a few more pics of the heads and roller chain installed. Hate to post it here but My brother was getting rid of his car and I had to aquire it so it set me back a little, not much. Its not an Iroc but we built the car together and I have a sweet spot for it. Just an awesome daily driver. Dont rag on me too much. Its a 1994 Mustant Gt Kenne Bell blown. Alot of bolt ons and after market parts to list . Just couldnt see the car go, and with 85,000 on it it would make me cry. Anyways back to the 421 here are the latest pics:
Would like to get my old combo super ram 355 sold , too many motors in my garage already. Take care all
Not much in updates, just a few more pics of the heads and roller chain installed. Hate to post it here but My brother was getting rid of his car and I had to aquire it so it set me back a little, not much. Its not an Iroc but we built the car together and I have a sweet spot for it. Just an awesome daily driver. Dont rag on me too much. Its a 1994 Mustant Gt Kenne Bell blown. Alot of bolt ons and after market parts to list . Just couldnt see the car go, and with 85,000 on it it would make me cry. Anyways back to the 421 here are the latest pics:
Would like to get my old combo super ram 355 sold , too many motors in my garage already. Take care all
#21
Re: 421 swap pics within
Thanks for the compliments. We got the valvletrain all set. went with Smith bros. pushrods, .116. 5/ 16wall pushrod with a shaft end on one side here are the pics:
Notice the slight angle on the pushrods into the lifter cup. With shaft system we used a .450 offset which is recommended by AFR. But to make pushrod completly parralell you need a .180 offset lifter. Problem is no one makes a hydralic offset lifter only solid. Jim checked and rechecked. A call to AFR comfirmed there is absoulutly no problem with the pushrods angle and no issues with longevity set up this way. So it seems to be the correct way using hydralic lifters.Take care all
Notice the slight angle on the pushrods into the lifter cup. With shaft system we used a .450 offset which is recommended by AFR. But to make pushrod completly parralell you need a .180 offset lifter. Problem is no one makes a hydralic offset lifter only solid. Jim checked and rechecked. A call to AFR comfirmed there is absoulutly no problem with the pushrods angle and no issues with longevity set up this way. So it seems to be the correct way using hydralic lifters.Take care all
#22
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Re: 421 swap pics within
Very nice. Should spank my little 421. I'm kinda building the other end of the spectrom. Smaller (210) heads and cam (236/242) but very close on the bottom end. I'm looking for a true-street version.
Interesting you stayed with the dog bones. I started to but liked the Comp short travel lifter better. Not much of a chance of colapse with them. You are running a lot of duration for a hyd-roller too.
What type of pan are you planning? I'm hoping to run (for now) my shorty headers and the cross over behind the cross member has me worried a bit with the deep pan. Oh well, there's always something that comes up with these type builds.
Interesting you stayed with the dog bones. I started to but liked the Comp short travel lifter better. Not much of a chance of colapse with them. You are running a lot of duration for a hyd-roller too.
What type of pan are you planning? I'm hoping to run (for now) my shorty headers and the cross over behind the cross member has me worried a bit with the deep pan. Oh well, there's always something that comes up with these type builds.
#23
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Re: 421 swap pics within
REALLY nice build. Any updates? I am currently looking for someone to build me a 421 street motor. No one local wants to build one.
#24
Re: 421 swap pics within
Nice build but I not sure about using a stock replacement dog bone lifter in that build. Are those lifters the ones with a .700 wheel??
High rocker ratio. I am sure you have a reduced base circle cam? plus push rod angle its going to be tough on stock replacement lifters.
Morel has a much better .842 HYD tybar lifter with a .750 wheel which is made for the lift and duration your using.
IMHO I would have went with a .904 HYD. lifter bigger body, bigger .810 wheel less revolutions around the lobe, bigger axel plus it will lessen the pressure angle as well.
High rocker ratio. I am sure you have a reduced base circle cam? plus push rod angle its going to be tough on stock replacement lifters.
Morel has a much better .842 HYD tybar lifter with a .750 wheel which is made for the lift and duration your using.
IMHO I would have went with a .904 HYD. lifter bigger body, bigger .810 wheel less revolutions around the lobe, bigger axel plus it will lessen the pressure angle as well.
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Very nice! Should scream up top!! I wouldn't be surprised if you exceed 550 HP considering how well it should breath...
A little curious as to why you went with 1.65 ratio intakes and a smaller ratio on the exhaust side? Makes no difference?
A little curious as to why you went with 1.65 ratio intakes and a smaller ratio on the exhaust side? Makes no difference?
#27
Re: 421 swap pics within
Thanks everyone. Jim does all his strokers like this. Engine exhaust flow is only important in the lower lift ranges because of pressure in the cylinder. Just the opposite on the intake side. Got a set of AFR valve covers. Now only need the miniram and monoblade. Injectors im debating 44 or 48lbs. Will update when it dynoes. Thanks all
Last edited by IROCZ1989; 04-24-2014 at 10:54 PM.
#28
Re: 421 swap pics within
Here's the latest with the valve covers. The AFR carb intake is temporary for possible engine dyno test. This valve train should have zero problems at 6500rpm+ with the Crane lifters and Ti retainers and upgraded AFR#8019 springs. I do like the factory type lifter hold down set up for street cars. It's about totally bulletproof. I have seen tiebar lifters break at the tie bars which would be a disaster. I have done a lot of motors with similar valve trains and had zero problems.
Oh... put a new Race Deckfloor in. That is the way to go, easy to clean and looks great. Those old composite tiles soaked up oil as they wear and you can never make them look clean.
Oh... put a new Race Deckfloor in. That is the way to go, easy to clean and looks great. Those old composite tiles soaked up oil as they wear and you can never make them look clean.
#29
Re: 421 swap pics within
Nice build but I not sure about using a stock replacement dog bone lifter in that build. Are those lifters the ones with a .700 wheel??
High rocker ratio. I am sure you have a reduced base circle cam? plus push rod angle its going to be tough on stock replacement lifters.
Morel has a much better .842 HYD tybar lifter with a .750 wheel which is made for the lift and duration your using.
IMHO I would have went with a .904 HYD. lifter bigger body, bigger .810 wheel less revolutions around the lobe, bigger axel plus it will lessen the pressure angle as well.
High rocker ratio. I am sure you have a reduced base circle cam? plus push rod angle its going to be tough on stock replacement lifters.
Morel has a much better .842 HYD tybar lifter with a .750 wheel which is made for the lift and duration your using.
IMHO I would have went with a .904 HYD. lifter bigger body, bigger .810 wheel less revolutions around the lobe, bigger axel plus it will lessen the pressure angle as well.
We are using the same lifter minus the tie bars. Base circle is 1.040. Lifter body .842
Last edited by IROCZ1989; 04-25-2014 at 05:26 AM.
#30
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Re: 421 swap pics within
Hey 'ROCZ any updates? We're done gathering parts on my build so hopefully there will be progress soon. I'm so ready to get mine done that hearing your update helps while I'm waiting. and waiting...
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Re: 421 swap pics within
Man those are some nice looking heads. I have raised port hogged out 230 brodix and they don't even compare to yours. That car is going to get it done up top. Good luck keeping it between the ditches.
#33
Re: 421 swap pics within
Have an update comming soon. Will be ordering the miniram next week sometime and it will be sent first to my porter Tom Moss well known 5.0 mustang porter who did my gt40 lower on my supercharged mustang. He is a wiz with port work. Then Jim is going to get the lower powdercoated black. We never did get the motor dynoed because the shop doing had personel inhouse issues that conflicted with our shedule. We borrowed the afr titan manifold and a guy was waiting on us and the time was running over. Antman , hang in there it will come together sooner than you think. Paitence, if you have it is a god send on these type builds. Splitty thanks for the compliments, they are a nice set. Badass355, price tag is not bad considering what your getting. Honest 600 crank hp with bullet proof bottom end. Really Jim builds a nice motor and parts are below cost. Figure tb to oil pan 12-13000. More hp than a blown smallblock, and 200 shot nitrous if you really want to play. One things for sure this type of build isnt for everyone. Take care guys.
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Re: 421 swap pics within
Yes, we'd like to hear more.
And patience is gold with one of these. Mine's together and running but it was about 7 months from conception to installation. And still there's more dialing in to do. Let's see I had to fab a new exhaust, pull the trans due to a glazed disc and now I am changing computer systems. Going with EBL Flash but that's another thread lol.
I haven't had a chance to dyno yet but went 8.1/89 in the 1/8mi so it's making some power. That was with a soft launch/tuning run so there's more in it. Had a clutch adjustment issue so it slipped the clutch hard on N2O but went 7.70/92 none the less. I did have some troubles getting the part throttle AFR where I liked it and the WOT fuel dialed in that's why I swapping over to SD. I also believe the MAF/intake tract/48mm TB is holding power back so I will eventually get that all swapped out.
A few things I learned is I probably could have gone with a tighter LSA (112 now) on the cam or a lot more compression (10.4 true CR). This engine idles like a kitten at 800 and only cranks with ~170PSI. Too late intake closing or needs more squeeze. No issues with detonation or spark retard. Also, I decided not to bore my block so I ended up with a 414 motor. If I had it to do over I would have built a bigger motor. Probably 4" and +.060 or more. Also, the CC short travel rollers & steel roller rockers along with a fairly quick high lift cam are fairly noisy. I may need to get a cast valve cover or come up with some other way to dampen the sound. It's not excessive but can be heard at a stop light.
And patience is gold with one of these. Mine's together and running but it was about 7 months from conception to installation. And still there's more dialing in to do. Let's see I had to fab a new exhaust, pull the trans due to a glazed disc and now I am changing computer systems. Going with EBL Flash but that's another thread lol.
I haven't had a chance to dyno yet but went 8.1/89 in the 1/8mi so it's making some power. That was with a soft launch/tuning run so there's more in it. Had a clutch adjustment issue so it slipped the clutch hard on N2O but went 7.70/92 none the less. I did have some troubles getting the part throttle AFR where I liked it and the WOT fuel dialed in that's why I swapping over to SD. I also believe the MAF/intake tract/48mm TB is holding power back so I will eventually get that all swapped out.
A few things I learned is I probably could have gone with a tighter LSA (112 now) on the cam or a lot more compression (10.4 true CR). This engine idles like a kitten at 800 and only cranks with ~170PSI. Too late intake closing or needs more squeeze. No issues with detonation or spark retard. Also, I decided not to bore my block so I ended up with a 414 motor. If I had it to do over I would have built a bigger motor. Probably 4" and +.060 or more. Also, the CC short travel rollers & steel roller rockers along with a fairly quick high lift cam are fairly noisy. I may need to get a cast valve cover or come up with some other way to dampen the sound. It's not excessive but can be heard at a stop light.
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Re: 421 swap pics within
Did you have any rodnto cam clearance issues? Thinking about doing a 414 build but don't want to run a small base circle cam.
#37
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Re: 421 swap pics within
I didn't check personally, I had the motor built. We did use a .900 base cam just to be sure and I have not had any known problems. There is about 5k miles on the motor and about 10 passes. What I've been told is the callies rods can be used with a std base cam depending on lift.
#38
Re: 421 swap pics within
I didn't check personally, I had the motor built. We did use a .900 base cam just to be sure and I have not had any known problems. There is about 5k miles on the motor and about 10 passes. What I've been told is the callies rods can be used with a std base cam depending on lift.
A standard base circle is the largest that'll fit for a given lobe lift.
A small/reduced base circle is when we go smaller then standard to get the nose of the lobes away from the rods.
A standard base circle for a .360" lobe in a standard SBC is 1.140"
A standard base circle for a .410" lobe in a standard SBC is 1.040"
A standard base circle for a .460" lobe in a standard SBC is 0.940"
I build alot of 421's I use a cam with a .420 lobe and the base circle needed to acheive a .420 lobe is 1.028 I need more cam to rod clearance so the cam is reduced to a 1 inch base circle and to get the a .420 the nose is now shorter. Now its a reduced base circle cam with a shorter nose.
Whether you have a .300 or .460 lobe the lifters at max lift in the bores will both be at the same height. If the lifters were higher in the bores the lobe would be higher then the journal of the cam and you could not install it. Most guys think with more lift the higher the lifter goes !! It dones not work that way. Lifter starts at the base circle. The more lift the lifter set down further in the lifter bore.
More lift = smaller base circle and if you need to lower the nose to clear the rods the you reduce the base circle of the cam.
To figure a what a base cirle size you have Lobe lift X two minus journal diameter = base circle. Its that simple
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Re: 421 swap pics within
Only the Callies HD rods will work with a STD base circle cam with a 2.100 journal.
A standard base circle is the largest that'll fit for a given lobe lift.
A small/reduced base circle is when we go smaller then standard to get the nose of the lobes away from the rods.
A standard base circle for a .360" lobe in a standard SBC is 1.140"
A standard base circle for a .410" lobe in a standard SBC is 1.040"
A standard base circle for a .460" lobe in a standard SBC is 0.940"
I build alot of 421's I use a cam with a .420 lobe and the base circle needed to acheive a .420 lobe is 1.028 I need more cam to rod clearance so the cam is reduced to a 1 inch base circle and to get the a .420 the nose is now shorter. Now its a reduced base circle cam with a shorter nose.
Whether you have a .300 or .460 lobe the lifters at max lift in the bores will both be at the same height. If the lifters were higher in the bores the lobe would be higher then the journal of the cam and you could not install it. Most guys think with more lift the higher the lifter goes !! It dones not work that way. Lifter starts at the base circle. The more lift the lifter set down further in the lifter bore.
More lift = smaller base circle and if you need to lower the nose to clear the rods the you reduce the base circle of the cam.
To figure a what a base cirle size you have Lobe lift X two minus journal diameter = base circle. Its that simple
A standard base circle is the largest that'll fit for a given lobe lift.
A small/reduced base circle is when we go smaller then standard to get the nose of the lobes away from the rods.
A standard base circle for a .360" lobe in a standard SBC is 1.140"
A standard base circle for a .410" lobe in a standard SBC is 1.040"
A standard base circle for a .460" lobe in a standard SBC is 0.940"
I build alot of 421's I use a cam with a .420 lobe and the base circle needed to acheive a .420 lobe is 1.028 I need more cam to rod clearance so the cam is reduced to a 1 inch base circle and to get the a .420 the nose is now shorter. Now its a reduced base circle cam with a shorter nose.
Whether you have a .300 or .460 lobe the lifters at max lift in the bores will both be at the same height. If the lifters were higher in the bores the lobe would be higher then the journal of the cam and you could not install it. Most guys think with more lift the higher the lifter goes !! It dones not work that way. Lifter starts at the base circle. The more lift the lifter set down further in the lifter bore.
More lift = smaller base circle and if you need to lower the nose to clear the rods the you reduce the base circle of the cam.
To figure a what a base cirle size you have Lobe lift X two minus journal diameter = base circle. Its that simple
The rods used on my build are CSA-6000DS2A2AH. I understand they can be used with "std" base cam depending on lift with a 2.1" pin/3.875" stroke crank.
My cam card specs don't give the base circle diameter but only states "small base circle". I was told it was .900" but in checking my build sheet on the motor is states ".860 BC" although I can't confirm it. Lobe lift is .375/.380".
I'm not a full time builder so if my comments were misleading/not enough information, I do apologize.
Last edited by antman89iroc; 11-28-2014 at 10:09 AM.
#40
Re: 421 swap pics within
Your comments caused me to do some further checking. I was quoting from memory before.
The rods used on my build are CSA-6000DS2A2AH. I understand they can be used with "std" base cam depending on lift with a 2.1" pin/3.875" stroke crank.
My cam card specs don't give the base circle diameter but only states "small base circle". I was told it was .900" but in checking my build sheet on the motor is states ".860 BC" although I can't confirm it. Lobe lift is .375/.380".
I'm not a full time builder so if my comments were misleading/not enough information, I do apologize.
The rods used on my build are CSA-6000DS2A2AH. I understand they can be used with "std" base cam depending on lift with a 2.1" pin/3.875" stroke crank.
My cam card specs don't give the base circle diameter but only states "small base circle". I was told it was .900" but in checking my build sheet on the motor is states ".860 BC" although I can't confirm it. Lobe lift is .375/.380".
I'm not a full time builder so if my comments were misleading/not enough information, I do apologize.
That is way to small of a base circle for your build that is alot of extra pressure angle on the lifter which is not a good thing. Plus cam flex.
If it is a .860 base circle it was not very well planned out.
No need to go any smaller then you have to.
#41
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Car: 89 IROC
Engine: 6.8 HSR N2O
Transmission: TKO 600
Axle/Gears: 9" Moser 3.50 True trac
Re: 421 swap pics within
You know, you're probably right. This is the first motor I didn't personally build. I was hoping to get "expert/professional" results but there's this and some other issues that give me reason to think they didn't pay attention to details I had expected they would. These were the types of details I thought I was paying someone to handle the right way. It goes back to the old saying about if you want it done right you have to do it yourself. However the shop I used produces a lot of competitive race motors so I thought I was in good hands. Anyway, I am going to do some further checking to see if that dimension is correct. Maybe Comp will have the exact specs since this is a custom grind.
#42
Re: 421 swap pics within
You know, you're probably right. This is the first motor I didn't personally build. I was hoping to get "expert/professional" results but there's this and some other issues that give me reason to think they didn't pay attention to details I had expected they would. These were the types of details I thought I was paying someone to handle the right way. It goes back to the old saying about if you want it done right you have to do it yourself. However the shop I used produces a lot of competitive race motors so I thought I was in good hands. Anyway, I am going to do some further checking to see if that dimension is correct. Maybe Comp will have the exact specs since this is a custom grind.
Your set up will work its just noT optimized !!
Last edited by HINKSON AUTO; 05-06-2015 at 03:05 PM.
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85Z28NOS (08-25-2020)
#44
Re: 421 swap pics within
The Crower stroker rods will work out of the box. They dont make them anymore. But for the same price as the stroker Callies rods about you can get a Crower stroker billet rods. My base circle is 1040 crane billet unit. Same rod dimensions, just in billet.
#49
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: 421 swap pics within
I have a canton pan like that as well, you'll like it.
LB9GTA There are a couple different part numbers for the pan depending on which block you use.
LB9GTA There are a couple different part numbers for the pan depending on which block you use.