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Wed Mar 23, 2016 11:08 pm

Well its time to pull the trigger on my build but I have some questions.

I have my hart set on a 1904 74 x 90.5 mainly because of the parts I already have (a pistons and 90.5 041's) I really like the idea that with 5.325 Porsche Length rod the engine will stay very close to stock width.

I plan on using a china forged 74mm crank and forged 5.325 I-beam rods from carcraft.

So I wanted to know if any of you guys have built a 74mm stroke engine using the china parts (Forged crank and rods). And if you ran into any problems like piston or case clearance? Are they just junk or an OK value option?

Also is the CB performance in/out oil pump to remote filter a bad idea over a full flow setup?

Thu Mar 24, 2016 12:44 am

make it a single port

If the case is already getting machined for cylinders, do proper full flow

Thu Mar 24, 2016 3:11 am

A friend and I are building one with a forged crank from AA, which I believe is chinese, as well as their forged flywheel, which I also believe is chinese, but with stock connecting rods and Mahle pistons and cylinders, and cb lifters and cam. So far everything is looking nice, even the Chinese parts look really good. We're moving slowly with the build, because we both work a lot, but the machine work for the case and heads is almost done.
In a few more weeks we should start putting the long block together, and it's all downhill from here...

Thu Mar 24, 2016 7:25 am

why would he want to use single port heads? all this would do is put a damper on potential performance.

Thu Mar 24, 2016 10:32 am

Well I have had my share of single port motors and that's not the direction I want to go on this one I already have a set of 041 heads with very low miles.
thank you thechief86 for the info that's what I wanted to hear.

I guess I should not be afraid of a little piston skirt clearancing but right now I cant decide if I should go with 5.325" rods or 5.4" rods.

Thu Mar 24, 2016 10:50 am

Do you have some stock rods just to test fit stuff with?

I'm running an 82mm crank in my '67 with .080" worth of barrel shims and non-flycut China heads with 60cc chambers -- fits fine. You may need .090" shims with stock rods, should still fit ok.

Stan

Thu Mar 24, 2016 3:48 pm

I'm using a 74mm crank, 5.4 h-beam rods and AA pistons from CIP1 for my 1904. No issues with fit or quality. I needed a .090 shim to get .040 deck height.

brad

Thu Mar 24, 2016 5:20 pm

yes i ran into a few issues with those parts. I had to hone out the small ends a little because they had virtually no clearance, the big end was ok for size but sure was thin, bolt heads poorly broached so had to make a custom 11.5mm socket to fit them.
Check the runout of the dowel pins on the crank, I found one the pattern was off center and it made fitting the flywheel a chore.

Tue Mar 29, 2016 10:46 am

i've been thinking about building this too cause i'm not sure about the 88mm slip in case machine heads pistons. i'd feel safer using the 90.5 pistons. i see your point on using the 5.325 rods. someone stated in another thread that you don't have to use shims and everything just bolts up together for heater boxes or stock headers or stock muffler. i thought about building this for my 70 panel to give it that extra torque to go up hills and such not to blow the doors off a mustang. so would it be possible to run it with a stock carb cause i don't like messing with duals that much and i don't want to cut the aircleaner bracket off. i just want it to look kinda stock. i know a 1776 works great with a stock carb and they say the 1800 can run a stock carb too. i don't care about top end it's a bus.

Tue Mar 29, 2016 11:05 am

Galen, i didn't know you had a panel bus lol...
I think you should do a longer stroke for a bus, that's a lot of weight.
It's not like you'll keep it more than a few weeks anyway haha
I'm hoping I won't be too disappointed with a 1904 in my beetle, guys on here say I need to spend more money on carbs....

Tue Mar 29, 2016 11:19 am

I plan on keeping this for a while this is going to be my swap meet bus. I have a couple nice block that are standard bore one is a super nice universal block that I can use in the bus. I'm just going to put a stock one in for now and sometime this fall build a motor. So I'm just trying to get ideas. But I'd like to run single carb.

Tue Mar 29, 2016 11:23 am

For a bus, 76x92 thick wall would be great with a single IDA methinks.

Wed Mar 30, 2016 8:21 pm

Well I pulled the trigger today and ordered the parts. fingers crossed assembly goes well.

Wed Mar 30, 2016 9:16 pm

thechief86 wrote: For a bus, 76x92 thick wall would be great with a single IDA methinks.

Why a single IDA? I'd run a pair of 44 kadrons before I'd run a single 2Bbl. Center mounted 2Bbl carbs are a PITA.

Although a pair of 40IDF on a 76x92... use tall manifolds and short stacks inside your filters... bet it would run like a stump puller. Keep the venturies on the small side... would be a nice daily driver engine in a heavy car.

OP-

I've test driven a 62 beetle with a stock trans, 165/80 tires, and a very nicely put together budget 1904 with cheap CW Chinese crank, lightened cast flywheel, CB rods, and a pair of properly jetted 40 kadrons sitting on stock valved single port heads. That car felt like a monster if you cut loose from a rolling start, and would chirp it's way into second gear! The guy who built it claimed 32MPG in commuter traffic, and I personally had no problem getting up to 90MPH on the freeway in it rather quickly. Use what you got was his motivation.

If you put it together with attention to the little things, balance everything, and use a decent cam specced conservatively, it should make plenty of torque and if cooled properly with all the proper tin and thermostat/flaps, it should last a good long while.

Thu Mar 31, 2016 3:04 am

Lingwendil wrote: thechief86 wrote: For a bus, 76x92 thick wall would be great with a single IDA methinks.

Why a single IDA? I'd run a pair of 44 kadrons before I'd run a single 2Bbl. Center mounted 2Bbl carbs are a PITA.
.
He said he wanted a single carb, and I've seen great results with a single IDA. My buddy's 2016 ran awesome with one.

Thu Mar 31, 2016 9:10 am

I've used the Empi cranks from Carcraft multiple times on low budget client builds. They all hold up for street use. Balancing is one of the most important aspects of the build. I would not use a single on anything tbh and if I had a say. I'd opt for Dell 36's or 40 hpmx/webers gone thru. Lot more range to get performance and mpg potential. A rebuilt working ida is like 350-400. That's just shy for an hpmx set.