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SBC 400 specs. will this be a good K5 engine?

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warreclipsegst

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Thought I would ask you all what you think of this SBC 400 I have that I was thinking of putting in my K5. engine dyno'd with the following.
RPM HP Torque
2000 136 357
2500 180 379
3000 218 381
3500 260 390
4000 290 381
4500 302 352
5000 288 303
5500 251 240
6000 203 177
6500 144 116
Then engine specs out with the following. .020 over, balanced and blueprinted, 5.7" rods, 9.6:1 comp., stock 76cc heads with upgraded valve train, 234 244 @.050 duration .488 .510 lift with 114 deg lobe seperation, edelbrock performer intake, 1in carb spacer, holley 750cfm, accel HEI dist, msd 6al ignition and wires.
tranny is a TH350 built with a 3200 stall.
 
everything but the stall looks good to me, looks way too high... good low end torque, good midrange hp...
 
For a blazer, pay no attention to horsepower nimbers, look at your torque. 300+ lb-ft up to 5000rpm, sounds good to me.
 
Looks like a nice low revving motor... Ditch that stall converter and go with a quality "Stock stall" converter. Why do people use Edelbrock Performers?? Its been tested that a Performer RPM wont hurt torque and makes more HP. And why a 1" spacer and 750 carb on a 300 HP motor that will never go over 5000RPM? Thats a big cam for stock heads. And 9.6:1 compression is pretty close to the limit for pump gas with iron heads. As long as it has some sort of warranty I think its alright.
 
The intake was free, the carb was free. The spacer is a TransDapt 4 hole swirl design supposed to help with low end. The cam is a bit large for stock heads but a similar motor was tested with a set of alum. heads, 64cc chambers 2.02 intake and 1.64 exhaust vlaves (that bumped comp. upto 10.8:1 over my 76cc heads with 1.94 1.50 valves) edelbrock performer rpm intake same carb and everything else and the numbers weren't much better than mine. about 100 more hp and 10-25 lbft more through out the range only it made more power in the upper rpms. I know alot more HP but the torque wasn't much better..

the 3200 stall is b/c this setup was intended for a car... the car project got scrapped and I threw it into the K5 but haven't ran it yet b/c i have 4 flat tires i need to get fixed. all shops i talked to told me i would ne atleast a 3500 stall with that cam and engine configuration. Tranny shops, engine shops, speed shops... i did alot of research before i put it together (for a car mind you) but why waste it when i have it.
 
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why does the torque look low?
my crappy motor is supposedly 195hp/295lb ft torque....
and after using desktop dyno with cam, heads, intake change I will be at 400lb-ft torque....
im just curious as yours isnt eve listed in the 400's.....

guess the other thing is that dyno numbers are before you do what you listed below it right? cuz that high of a lift you should be higher.......

I was going to go with a .474 lift cam but realized that my power starts at 1200rpm-5500 rpms....
so I went with .458 lift cam and will be idle - 5000rpms....
this is with the .474 lift cam....
Worked%209C1%20Xtreme%20Cam.JPG
 
STOCK HEADS... stock heads with stock ports with stock sized valves hurts on torque and HP. The 400 with aluminum heads and bigger valves made over 400 ftlbs but it really made up the difference in HP being around 100 HP higher than my setup. this was with the same cam, bottom end etc. but with 64cc heads which also bumped the comp. upto 10.8:1. also i probably have too much carb. looking to goto a 650 or 670cfm..

I have another 400 longblock sitting in the garage that im thinking of making into a stroker. Destroke it to 377 cubes and you've got one high reving, high hp and full of torque motor....
 
Your gonna hate that stall. Imagine, you will have to rev up to 3200 RPM to move that thing. It will suck in parking lots, driveways, slow moving on the trail. You will burn up the tranny when cruising at 2500 RPM. Better get a HUGE tranny cooler. I had a 2000RPM stall converter for a month in a "hot rod". It sucked!! My current 425-450HP 388 has a converter with only a couple hundred more RPM stall so it can idle at 800 RPM.
 
As for your stahl your way off, people suggested a lower one and they are right. I run a hydraulic roller with lift at 510-520 on 110 seperation from comp and they only reccomend my stahl be 3000.
 
I don't make any claims as to be a torque converter expert. that is why i did research on the matter. I don't like doing things more than once. I've had 5 reputable shops tell me i needed that stall and summit racing even said i would need that stall when i ordered the cam. I thought it was high myself me and a buddy built a 350 for his nova with a slightly smaller cam and ran a 2000 rpm stall in his car with no problems. Im not saying i need that high of a stall just what i was told. that is why i am asking what you guys think. never built a 4x before...
 
what's the rest of the K5?

I'm assuming 2wd if you plan on using the car th350... I believe to use it in a 4wd, you've gotta change the tailpiece.

just for comparison:

my 84 burb, w/ a .60 over 350, 9.5:1 compression, mild rv cam, edelbrock 1406 carb, all the electrical goodies idles @ 650 rpm... I believe I am running a 1200 stall through a 700r4 into the 208... 3.73 gears... 32" tires...

my engine rarely sees over 3k rpm... 65 in third gear turns 3200 pulling a 5k load.... rpm drops to 1800 at 75mph in OD...
 
K5 is a 4x4 switched the tail shaft out. This thing will idle at 600rpm if i want it to and it will do that in gear as well. as for reving to 3200 to get it to move thats not the case. with 4 yes 4 flat tires and being low on tranny fluid i only had to give it a small amount of throttle to move it. no where near 3200 maybe 1200 at most... and yes i do have a big ol tranny cooler to go with my big ol radiator!!
 
I dont put much into what the people that answer phones say at summit or jegs, call the cam manufacturer and give alot of info to them.
I run vortec heads and love them, machine work for stiffer springs, guide plates, more expensive roller rockers (narrow body without self-aligning tips)
 
The cam specs is why eveyone i have talked to said i needed that high of a stall.. no one can intelligently recommend a stall converter without cam specs... and if you are up on your tc's then you know that a converter will stall differently on every engine. it is based on hp and torque of the particular engine it is attached to. a 3200 rated converter might stall at 2500 on a 250hp sb but put that same converter onto 500 hp sb and it might stall at 3800 or 4000 rpm (these are #'s i pulled out of the air for an example).
 
I was going by your cam specs, this is the reason I gave mine as an example, remember 510-520 lift with 110 center, sounds like your happy with your converter so run the pos.
 
no need to get your panties in a bunch. just shooting back info as i recieve it. never said i was happy or unhappy i don't know yet b/c i haven't been able to drive it yet. and with due respect your cam specs don't matter b/c it is a roller and mine is not. you can run more lift with a roller cam. thats why people switch to them that and less friction = more hp.

maybe it does sound like im defending it... but im not. just trying to see what people think and why and trying to let them know why i went with it. it's easy to have an opinion. it's better to have an educated one...
 
The higher stall is gonna be great for drag racing and such. You can slap a regular converter on it and cruise just fine. Ive done it for years. It helps for regualr driving, and slow going. Try it out the way it is, if you dont like it you can just swap in a lower stall. Ive even done long dirves and stop in go in 90+ degree heat.
 
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