Do you drive it with a solid flat tappet?When I freshen up the R1 in my Dart the lifter bores will be bushed.
Not always necessary I ran a .557 and a .590 cam no nothing for over a decade.Do you drive it with a solid flat tappet?
This is a new build with a new R block, i will bee doing bracket racing only so its a drag car.
I belive that the comp will get to about 13.5
The heads are not done yet, bought them of ebay and now they are being redone the plastic.
I am considering to have the lifte bores sleeved or not to do it. Calculating the cost vs horsepower gain would be my issue.
Mushroom lifters what is that? Do you still have to block of the oil to the lifters?
we ran GK mushrooms in the AMC trans am car
they really work but are a real PITA during development
actually the increased acceleration is due to starting the sweep further from the center of the lifter
it can actually be less "agressive"
and a mopar size profile can be less agressive than a chevy and till have more acceleration
old wives tale that .904 profiles are harder on parts- but of course you can build a cam that you have to change spring on often with either size lifter- but with the mopar lifter you do not HAVE to to beat the chevies, who are also handicapped by their short rods
for example both Crane and Engle had 3 series of lobes god knows how many comp has
I'd call them streeet, street strip and trailer
I had one in a TA engine I never ran, had it 10 years, had a 3.466 8 bolt crank, Hemi footprint rods, dre under the pistons from Atlanta 4 bolt mainsI'm hoping someone still has mushroom lifters. Maybe Jim at RB. I need to start making some phone calls. I may not be able to even get them any more.
Do you drive it with a solid flat tappet?
What’s thick?old school keep the walls thick
Probably a 4.060 bore would help in getting rings and maybe even pistons.
Ok got the X block.
It’s in nice shape, as in fresh bore of 4.040 new cam bearings. Clean.
I assume it’d be a good idea to install 4 bolt mains? It looks like it would favor a splayed 4 bolt cap setup?
I text my machinist and asked to sonic test this block, when he has time.
He of course responded are we gonna build a 440” small block? I said depends on the sonic test.
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I would think un shrouding the valve a win win. Those w5 heads we have need a big bore and stroke to work.Why go more overbore than you have to?
I did find nice pistons and rings for my R block. Going 4.04 bore.
Just trying to learn![]()
I would think un shrouding the valve a win win. Those w5 heads we have need a big bore and stroke to work.
If you have the material why wouldn’t you?
I’m fairly conservative, and plenty of people have went much further, so I will error on the side of less.
It’s a caged street car, I want to live on 20-60 mile trips repeatedly and not get hot.
Maybe a half dozen trips to the drag strip a season.
The guy I’d like to wear out before he gets any more decrepit, has run a best of 10:17 usually runs around mid 10s doesn’t really drive it on the street though anymore. I will.
Gonna take something serious to get in the 10:00 range high 9s would be better.
My machinist is super conservative, so he won’t recommend anything near dangerously thin, or even thin. He’s a PIAFABO member @Rocket has the caps you want for a great price. Splayed caps are overrated.
Nice pick up. If it sonics well 4.125 is a good starting point.
There is something to be said about ring seal, deck thickness and cylinder wall thickness. Try and not give up any more than you need.
At 4.100 you would have most like a good couple more bore jobs in it. Maybe 4.06-4.08 is a better start though I get it.parts availability and off the shelf rings
then enough for later rebuilds
mopar bore spacing is greater than sbc but the cylinders/ deck height is almost .600 taller so you get more flex at the same wall thickness
It’s a over next winter project, that I will be prepping the block for soon.too thin walls and you go slower and ring life goes away and you run hot
been there done that
let;s see what the sonic test shows
did you say whose pistons and cr?
how about a recap when your results come in
is this a siamese block?
chevy is siamese at 4.125 with a 4.40 bore spacing