so i was donated a sbc 400 its already been bored and everything on it checks out , so im going to build it, its already got a set of dished forged pistons in it.

but im going to have to see what the cr with the 74 cc heads will be before i descide if ill use them

its a 2 bolt 400
going with a comp xe268 , twin gt3582's, procomp 210 cc 74cc chamber cnc heads , unfortunatly for now im going to drop the tpi on it

and im just going to transfer the rest of the turbo system over from my current 355

anywas i have to get back to work but ill get some pictures posted up later tongiht and more as i start assembly

 

If you have a .040 deck+gasket thickness and 28cc dish you'd end up at 8.5:1 or so with those slugs, 9:1 with a 21cc dish, 9.5 with a 15cc dish. Summit has a 36cc dish but I'd be totally amazed if you had em. Here's to hoping for a fairly big dish.

 

just from picking the pistons up and looking at them im going to say they are a 21cc or better dish , could be a 15cc but they look to big to me to be that small of a dish

id be really happy is they are a 21cc , i like to shoot around 9.0-1 to 9.5-1 for my turbo builds

at my altitude i could safley run a 10.5-1 cr with boost on pump gas, but the minute i drive down to aroud sealevel to 3k ft above id prolly run into issues

im at 6,500ft above seal level

 

alright my friend just called me back as he got the pistions dishes poured and they are 15cc dishes

so with 0 deck , and a .040 gasket were sitting at 9.46-1

the engine is also only .020 over so only 404.5ci lol not a big deal , just glad the pistons will work as the selection for a decent .020 over piston isnt good

he did mention piston to wall clearance is a lil tighter then id like but im hoping when we hone it we can open it up just a tad


block needs a hot tanking for sure so hopefully ill get that dropped off this week if i can find a shop around me thats reasonably priced

 

Nice, sounds like you're in really great shape actually. Should be a beast I'll be curious to see what the PC heads do. Then again I would think the people who actually do the final machine work on them make a lot of difference short of something like porosity, inadequate material in key places or core shift.

 

thats whats generally said about them this will be my first time using them.
place i got them from buys the bare/raw castings and finishes them.

i will be checking valve train gemoetry and pushrod lenght carfully when i assemble them.from what ive been told i will need adjustable push rod guide plates as well


if i have to stick my tpi on it i expect the tpi is going to bottle neck the entire thing, might have it sold to replace it with single plane efi and 4 bbl tb

 

Unless you have aftermarket parts good luck with that. I got a whole one here for $50 from injectors to TB. I don't think I'll build another one considering how much of a pain they are with accessory brackets and just general assembly. This HSR is way easier.

 

lol if u picked one up for 50 bucks u got a deal and half

 

ive been seeing some sbc efi single planes on ebay w rails for good prices. can use a 90elbow and a ebay ls 90mm throttle body. i have on my fast intake and it was like 175$ shipped new. have used a total of 3 and all of them have worked well.
i just made an elbow from 3.5 aluminum tube. and 3/8 plate 6061 for the 4150 flange and tb flange. made the flanges on a drill press. from scrap plate i had. came out real nice.
if u can weld aluminum. u can save a few bucks there.
can prolly even make out of mild steel w 1/4 steel plate for the flanges. easier to weld also.

 

thats what i thought about doing but it seems the 4bbl tb has better air distribution then using an elbow and ls or other tb


the ebay efi intake is prolly what im going to go with , u can get one with rails for around 179$'s

 

yea. the 4bbl tb are real good. shouldnt b hard at all to run the throttle cable. very similar to a carb cable. and can use a ev carb hat. all the hi hp blo thru guys use it with good results. but turbonetics used to sell a carb hat designed for blo thru turbo engines.

 

My pile of cheap junk lol
Hmm pics won't upload from my iphone. Have to upload from a computer

 

here we go

edit i dont know whats going on with the attachments so ill upload to pb

 

ive decided not to use the 406 in the iroc , i dont think i can trust the factory block enough for the power its going to make, maybe ill just use the 406 longblock in my truck and drop the tpi on it.
but on the other hand the 350 in the truck already gets horrible gas mileage ( 6-8mpg in town) so im not sure how much worse the 406 would make it