hammertime

how did the converter swap turn out ?

Tod74

Please explain? I have seen the SLR charts before but do not understand why a 4.86 is too much for 1/8 mile.. as long as it doesn't spin and the motor is still in it's powerband at the end of the run....I run a 5.14 gear with a 4.25 inch crank...but it is a heavy car. around 3100 lbs. 60 fts low 1.30's

The converter advice I agree with ...just trying to understand how a higher gear would pick up his short times if traction isn't a problem

I972Nova

Sorry guys, It still ran the same.

I went from 5.895@117 to 5.923 all weekend at Pacemakers. I runner upped on Sunday (took 7 rounds and only paid $200r/u 800 win), but it makes me feel silly to have a bbc dragster that runs 5.90's

I think the compression is lower than I thought...

I have world merlin 320 runner heads with 119 cc chambers and a trw pistons with a .580 dome. The pistons had to have .090 cut off for piston to valve clearance with the big 2.300 valves.

I really just dont understand it, my $2000 flat top 406 with a flat tappet cam is faster than this 468 with pop up pistons and a .722 roller...

Wow, I guess I must need a new shortblock?

I had the timing at 36 degrees then bumped it up to 42 and it popped, is 36 a good place to start.

topcat572

Tod, to answer the best I can. The SLR chart is an old ATI chart for figuring startling line ratios. It takes Your rear end gear(4.86) and multiplies it by 1st gear in tranny(1.80)? and gives You a SLR of 8.75. An ideal SLR for a 4.00" stroke in a 2000 lb. car is 9.00. You are close, I corrected ,my self above after doing the math. Any way, if Your number is too high, it hits the tires too hard, If its too low You are not hitting the tires hard enough. A lot of hook problems were starting to develope when all these Low tranny gear ratios were coming out and people were just killing the tires. My dragster with the 4.500 stroke and same weight, I am way under with my 1.80 x 3.89 rears, when I get the 4.30s in there, Ill be just about right. My ideal SLR is 8.00, due to the increased stroke. :wink:

topcat572

When You bumped to 42, could it have leaned it out? If You are running a crank trigger, did You rephase the rotor? : This is the 2 things I would look for if it was mine, not saying they right. ops:

I972Nova

its a regular MSD 85551 distributor, The plugs were pretty good in color. I put the timing back and it doesnt pop now.

I972Nova

figured out why it was so slow at Super Chevy... I ran 9.23 then 9.29 then 9.41... Now I have 4 pounds of oil pressure...

I would say it was built tight and spun a bearing. I havent pulled it apart yet. 19 passes on it and its junk, oh well there is always next year.

I972Nova

Well I pulled the pan off and ALL 5 main bearings are destroyed, 2 are through the copper. The crankshaft is a total loss.




22 passes on these bearings!!!

I would say this is a good reason why the 468 was slower than the 406...

v8Fiero

:shock: WOW I wouldnt go with that engine builder again! Have you contacted him yet about it?

I972Nova

If he said he would fix it free, I still wouldnt want it... I am going to bite the bullet and go to the best guy around here, when i get enough money. It took me 8 months to finance this one.