aluminum block is in

vector1 · #1 (**permalink**) 06-10-2008, 06:05 PM

getting ready to put stuff together. it is kinda nice to be able to pick it up and carry it around. allied motors which is now bessel motorsports did a good job on the machine work. even weight matched the pistons. scat crank purchase was mis-handled so he substituted a crower crank, little heavier then what i was wanting but very nice. balanced the crank to .13/.21.

quickjack · #2 (**permalink**) 06-11-2008, 08:51 AM

Nice. Dart block, what are you building?

vector1 · #3 (**permalink**) 06-11-2008, 11:06 AM

it'll be a 400ci efi motor with dry sump or a fms 395hp crate motor if it doesn't work out.

David-JBL · #4 (**permalink**) 06-14-2008, 07:23 PM

Nice block. I look forward to more pics.

David

vector1 · #5 (**permalink**) 06-16-2008, 05:51 AM

had to take the block and parts to another shop. piston pin clearances weren't correct and i am having the rest of the clearances checked, sort of an insurance policy. i have the mics to check clearances but i am going to have someone with more experience check them. so the saga continues.

vector1 · #6 (**permalink**) 07-02-2008, 03:58 PM

got the block back today with some of the clearances checked. seems to be $75 well spent. the mains were too tight-.0015 to.0018, dart recommends .003. cylinder bores had a bit taper from top to bottom, 5 out of 8 srp pistons were pretty close in size and will have to be matched to cylinders to get the correct clearances because of the other 3. will have to purchase .001 under bearings for main and rod bearings.

with all the hassle and the money i was supposed to save keith craft would have been a good alternative but i guess the lesson is priceless

olddog · #7 (**permalink**) 07-03-2008, 07:31 AM

Are you sure 0.003 is the correct clearance for an aluminum block? Aluminum expands a bunch with temp. The aluminum Modular 4.6 calls for around 0.0015 if memory serves me.

A local builder told me that he has never seen a new block from any company that was ready to assemble. They all need to be checked and many things need corrected every time. So, don't feel bad. Be glad you had it checked.

Also clean it and clean it and scrubb it and clean it every way and every angle you can think of. Casting sand in a new block can kill your engine. After you are absolutely positive you have every oil gallory and water jacket completely clean, clean it three more times.

madmaxx · #8 (**permalink**) 07-03-2008, 07:38 AM

I know when the ZR1 came about in the early 90's with an aluminium block the main bearings were .001"

vector1 · #9 (**permalink**) 07-03-2008, 08:02 AM

when i called dart the guy checked with their engine builders on the main clearances. he did admit they were winding them pretty high @ 1500hp so i'll take it with a grain of salt. i guess it depends on wt. of oil using, but i told the guy 10w30 and he said that was a good oil and was pretty sure on the .003 mains. i'll prob end up with around .0025 to .003, but he said not to get into the 2's and initially said .003-.0035 and .003 on the rod pins. i would think idle pressure would be pretty light with those clearances, although idle doesn't take a lot anyway. also, this is with priority main oiling and you prob couldn't run those clearances if it had to go through the valve train at the same time.

olddog, i'm gonna need some more fingers after about the 5th cleaning if you have any extra.

vector1 · #10 (**permalink**) 07-03-2008, 08:13 AM

there's a pic of the pseudo longblock. torqued the heads on to see if we could get the cyl liners to settle a little bit. anybody have an oven i could borrow?

vector1 · #11 (**permalink**) 08-26-2008, 03:20 PM

there's the shortblock of it all.

second machine shop was better but still had to work to get everything where i wanted. x bearings ended up being too much clearance, .003 range, after they resized the crank mains to all the same measurement and touched the block with a boring bar so i ended up using reg bearings and was in the low 2's which is where i wanted to be. funny how 5 pounds either side of rec torque can net 2 tenths. also learned to keep fingers off the gauge if i was to get repeatable measurements. crank throws were polished but not checked and i ended up splitting a set of bearings to get the clearances at around .0024 with one at .0026, little more than i wanted but best i could do.

after i got a couple pistons installed i checked the deck and they were around .025 out of the hole so somebody was fudging somewhere and i had to get thicker head gasket.

degreeing the cam was kind of interesting. watch the gauge take up the lash of about .010 then all of a sudden it starts to climb pretty fast and goes through the .050 measurement spot on, amazing.

things are back on hold right now while i get some pushrods, longer rocker studs, and other misc.

more pics in couple weeks.

vector1 · #12 (**permalink**) 09-08-2008, 05:04 PM

Great Asp · #13 (**permalink**) 09-08-2008, 05:15 PM

Vector,

What clutch did you go with?

VERY nice looking mill BTW!

Eric

Mac VABCH · #14 (**permalink**) 09-08-2008, 09:26 PM

Vector,

Great looking engine. We are doing much the same thing. I am having KC build a 363 Dart block 8.2 deck height, ~13/1 C/R motor with AFR 205s. Also I have purchased a QM 7.25 clutch. But I am using a light weight Flex Plate and Button fly wheel assemble. I got the button from QM with the clutch and the flex plate from Quick Time. I'm not sure how much the button weighs but it can't be much and the flex plate weights 2.1 or 2.7lbs. I also have the MasFLO EFI what size injectors are you going with and is that the victor JR intake or the SR...Thanks Mac

vector1 · #15 (**permalink**) 09-09-2008, 05:31 AM

wow mac,

i was looking for something like that clutch setup and thought i had it pretty close. i'd be interested in pics or what part #'s you ended up with, course sounds like you have a track car going so this might not be streetable. my whole flywheel/clutch setup weighs 17 lbs. by the way purchased from levy racing.

on my efi i ended up using the accel gen 7 and they use a sup victor which i at first thought was too big for 400 ci, but since it is fi decided it would be alright, just didn't want to loose a whole lot of bottom end for driving. the sup vic does match up real nice with my afr205's on the ports so i was kinda relieved. the injectors are 44 lb units if i'm remembering correctly.

kc makes some nice stuff and don't think they can be beat for the money. what kind of hp/tq numbers are you looking at with this?

cheers

mark

Mac VABCH · #16 (**permalink**) 09-09-2008, 06:23 AM

Vector1,
Yes my car is strictly a track car, I don't think that the clutch and C/R will be very streetable. As for the clutch that you have I have attached some links, the 2nd link is the button flywheel for your clutch and the 3rd link is to the quick time web page for there flex plates. If you went that route it would be lighter than the setup that you currently have because the button is just so small. But it might not be very streetable. The 1st link is the clutch that I am using, with the same size button...You car and motor look great...Mac

[url="http://www.racingclutches.com/product.phtml?p=37&cat_key=81"]

[url="http://www.racingclutches.com/product.phtml?p=66&cat_key=51"]

[url="http://www.quicktimeinc.com/flex.html"]

vector1 · #17 (**permalink**) 09-09-2008, 08:56 AM

thanks mac that looks like a pretty nice setup. i was wanting to do something like that but couldn't make it work. i would be curious what the total wt. was though.

Mac VABCH · #18 (**permalink**) 09-09-2008, 10:08 AM

I will let you know in a few weeks when I get back in the states...Mac

mpanten · #19 (**permalink**) 09-11-2008, 06:36 PM

Since we are discussing dart blocks, does anyone know if I have to take the motor out to replace a rear main on an aluminum 351 dart block?

vector1 · #20 (**permalink**) 09-11-2008, 08:41 PM

if i was to change it on mine i would have to unbolt the transmission, remove the flywheel, drop the oil pan, take off the rear 4 bolt cap, and squeegie it in between the block and crank then reinstall the main cap. if i was unable to fit it between the block and crank i would have to drop the crank slightly by loosening the other caps.

the seal is a one piece affair and there is quite a bit of squish when the cap is installed so i don't know if you'd be able to insert it without dropping the crank.

that would have have to be some leak.

if you do replace it cv products sells a seal for dry sump engines that has double lips that would be the one to use. i have the part # in the shop if you decide you want to bypass cv products, they are slightly expensive.