post me some questions

[grumpyvette]

each head design has a differant deck thickness, but generally you can mill about .050 off head decks , your machineshop should know enought to keep you out of trouble, but remember the compression goes up, clearances between valves and pistons tend to get tighter and the intake may need machining to seat correctly after the heads are milled.

in some cases you can vary the valve train geomety enought with valve lash caps, which are cheaper than pushrods

the only way to verify the correct length pushrods is to verify the rocker and valve train geometry, these links and the sub linked info should help

 

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=1376

Edited April 14, 2009 by grumpyvette

[attworth]

Thanks again Grumpy. You're surely a wonderful source of information (and probably a really nice guy too.)

[mossy74]

Grumpy I've got a 327 SBC that was rebuilt about 10 years ago but has only done about 2000km's in that time so I'm not going with an engine rebuild at this time, to my knowledge the motor is standard but before I put the engine back in I wanted to put a performance cam in and some aluminum heads but not sure what to buy. When I do get to a full rebuild I'd be happy with 400hp max, it will be a weekend car only, I also have a rebuilt t5 with the heavy duty gearset so i imagine hp would be limited for the t5.

[grumpyvette]

It would help a good deal to know the compression ratio, and the cars rear gear ratio, and any other info you can supply, those older 327 were quite varied and knowing the head casting numbers would also help!

If performance from the 327 sbc is the goal,In most cases ID strongly suggest a solid lifter flat tappet cam be sellected to take advantage of the engines potentialy high rpm power band, but unless I know the rear gear ratio and the cars intended use,that might not be a good idea.

Edited April 22, 2009 by grumpyvette

[mossy74]

It would help a good deal to know the compression ratio, and the cars rear gear ratio, and any other info you can supply, those older 327 were quite varied and knowing the head casting numbers would also help!

If performance from the 327 sbc is the goal,In most cases ID strongly suggest a solid lifter flat tappet cam be sellected to take advantage of the engines potentialy high rpm power band, but unless I know the rear gear ratio and the cars intended use,that might not be a good idea.

 

Coludn't find out the compression ratio, I couldn't even find a casting number on the heads, the only number I found was on the block which was 3914660. I have seen some procomp aluminum heads on ebay here in oz but I'm not sure what the quality would be like compared to say the dart heads.

 

For the carb I was going to go with somthing like a holley 650, the diff ratio is 3.54 and its doubtful the car will see the track, I just want a powerful lumpy idle weekend car.

 

cheers

[grumpyvette]

we used to build a lot of 327-331 engines when I first started hot rodding

327 sbc engines really do like a mild solid lifter cam so they can both rev freely and pull decent low rpm torque, if you had higher compression and a 3.73-4.11 rear gear ratio, you could use more cam durration,like the isky z25, but the z20 isky does a decent job as a street/ strip cam, and its better matched to a car engine used for transportation

 

heres iskys ph# phone: 323.770.0930

 

If you can live with A LOT less low rpm power and mostly a free reving high rpm combo with that t5 trans an isky z25 will be alot less street freindly ,but youll certainly get the low rpm lope and more high rpm peak hp.

 

http://www.iskycams.com/onlinecatalog.html the isky Z20 solid lifter cam ..."chevy section,pg 86 "

and a decent dual plane performance intake like this

 

http://store.summitracing.com/partdetail.asp?part=WND%2D8501&autoview=sku

 

http://store.summitracing.com/partdetail.asp?autofilter=1&part=TFS%2D30400001&N=700+115&autoview=sku

 

I would NOT SUGGEST YOU GET PROCOMP heads , I keep hearing about variations in quality control issues

 

heads like the BRODIX IK 180cc or TRICKFLOW 195cc

designed for a combo like your building should work out fine,with that manual transmission provided you add decent full length headers and a low restriction exhaust

the cams reasonably mild but if you had much more durration it would raise the low rpm power bands torque curve to far to be easily use as transportation vs a performance only combo that a larger cam would transform the combo closer into being

Edited April 24, 2009 by grumpyvette

[mossy74]

thanks grumpy!

[deja]

What is your opinion on chromemoly pushrods as oppossed to hardened steel ones for my LT1 build? The engine is a 4 bolt GM crate 5.7L LT1 short block but will have a GM LT4 hot cam kit with springs and 1.6 roller rockers. Heads are reworked stock '95 LT1 heads. The car will be mainly street driven with an occasional trip to the drags. I am lookig at comp cams 7608-16 or 7808-16 pushrods. Are the chromemoly ones (7608-16) worth the extra money for my needs?

[rsicard]

deja: Before ordering the pushrods, use an adjustable push rod with the new rockers and reworked heads. If the rockers are self aligning there is no need for guide plates. If not then guide plates need to be added. In either case use 5/16" hardened .080" wall pushrods. I am building a similar SBC and have been through this process. Be confident that the valve springs are up to the task.

[Careless]

if anyone building SBC's need some parts, I have a friend who's making room in the garage. he's got a lot of neat stuff, let me know! some parts of which grumpy may be recommending to take into consideration for your builds. just trying to help a fellow Z'er (Z28, still a Z!). He's settled on another build and needs to clear-out for more room.

 

not trying to thread jack, but it might be worth while to inquire.

 

I mention this because rsicard mentioned guide plates, and he's got a set of all that stuff, so hey... why not!?

[grumpyvette]

as rsicard pointed out, getting the valve train geometry correct by verifying the correct pushrod length is mandatory, the chrome moly pushrods tendto flex less andat high rpms that can be important to the valvetrain control, I doubt it makes much differance on a stock or nearly stock combo but add, stiffer springs and spin the engine over about 6000rpm and you can at times see a differance

 

Careless

why not post a list of parts with pictures and prices on several sites, craigslist etc.

 

 

http://forums.hybridz.org/forumdisplay.php?f=141

 

http://forum.grumpysperformance.com/viewforum.php?f=88

 

http://www.chevytalk.org/fusionbb/showforum.php?fid/95/

Edited April 27, 2009 by grumpyvette

[deja]

Thanks grumpyvette. I will NOT be pushing this engine over 6000 RPM.

[rsicard]

Grumpyvette: I had asked you before about the strength of a 2 bolt versus 4 bolt main SBC blocks especially those with 1 piece rear main seal. I have also spotted girdles for 2 bolt blocks and valley girdles also. Please see http://www.horsepowersales.net and evaluate and comment please about using these valley girdles and crankshaft main cap girdles concerning strenghening the block. Your thoughts please.

[deja]

The rockers and springs are the 1.6 that came with the hot cam kit and are self aligning. The only machining on the heads was to true up the mating surface. I will get my hands on the adjustable pushrod just to be safe. The comp cam hardened pushrods I am looking at are 5/16 in. Dia.; 7.195 in. Length which I assume to taking into consideration the machining done. Stock is 7.2".

 

deja: Before ordering the pushrods, use an adjustable push rod with the new rockers and reworked heads. If the rockers are self aligning there is no need for guide plates. If not then guide plates need to be added. In either case use 5/16" hardened .080" wall pushrods. I am building a similar SBC and have been through this process. Be confident that the valve springs are up to the task.

[grumpyvette]

Grumpyvette: I had asked you before about the strength of a 2 bolt versus 4 bolt main SBC blocks especially those with 1 piece rear main seal. I have also spotted girdles for 2 bolt blocks and valley girdles also. Please see http://www.horsepowersales.net and evaluate and comment please about using these valley girdles and crankshaft main cap girdles concerning strenghening the block. Your thoughts please.

 

the first thing ID point out is that the chevy blocks are far less prone to cracking from flexing than the ford blocks and that anytime you exceed about 550-600hp your much better advised to use an aftermarket DART BLOCK with its much thicker cylinder walls, main webs ,and block endwalls, before spending hundreds of dollars on machine work, but the chevy block will stand up to a good deal more abuse than the sbf generally will if its correctly machined, read thru the links, JOBYs turbo build on a STOCK short block lasted for quite awhile under higher loads

lets put it this way, Ive built over 175-200 engines in 39 years (6-8 a year)and Ive never seen a block crack thru the lifter gallery unless it was the result of a rotating assembly grenading and that was usually at over 6000rpm, with obsurd levels of nitrous used, chevys crack cylinder walls, main caps, main cap webs, and decks on occasions but even the stock chevy blocks take alot more abuse than stock sbf seem to from what Ive seen

 

http://www.dartheads.com/products/engine-blocks

 

http://forum.grumpysperformance.com/viewtopic.php?f=69&t=636&p=850#p850

 

http://www.adperformance.com/index.php?main_page=index&cPath=69_82&zenid=0aaf0a17ddbd33634a85e31f4062f2a0

 

http://forum.grumpysperformance.com/viewtopic.php?f=51&t=47&p=56&hilit=+dart#p56

 

http://forum.grumpysperformance.com/viewtopic.php?f=51&t=439

 

http://forum.grumpysperformance.com/viewtopic.php?f=51&t=976

 

PS, what does that lifter valley brace really do that the correctly bolted in place chevy intake maninifold not do, IE provide a solid linkor brace between the cylinder banks

Edited April 27, 2009 by grumpyvette

[Kingnothing616]

Hey grumpy, you have seen my build of the 76 280z with the 283-powerglide combo... After getting everything running and put together I have put about 200 miles on it, and it seems that from a dead standstill im driving a 22r and taking off in 3rd gear. My boss at the shop i work for is a hot rod fanatic, and drag races professionally, he made sure everything was in working order with my motor just incase I overlooked something. I'm pretty sure its just the motor- tranny combo giving me fits. The powerglide only had 65k when I pulled it out of the car, put a B&M Transpak in it, TCI Saturday night special converter, fresh fluid, vaccum hooked up, kickdown hooked up and adjusted, etc. I'm pretty sure that im going to throw in the th350 that my buddy has so that I can use the factory shifter and everything. Just thought I would get your opinion, maybe different stall? Transmissions are not my category.

Thanks

Coye

[rsicard]

Grumpyvette: Another question. In the build of my Gen I SBC, I intend to eventually go to fuel injection. This will have knock sensors. Right now I have a single row roller timing chain because I have to fit a reluctor wheel ahead of it and shorten the snout on the balancer. I would really like to use a Quiet gear drive versus the chain but the manufacturers say this interferes with the Knock Sensors. My question to you is have you seen any acoustic data on the gear drives and knock sensors? At what frequencies are the knock sensors most active? What is the acoustic signature of the Pete Jackson Quiet Gear Drive if you know?

[grumpyvette]

rsicard

 

 

Ive run a jackson QUITE gear drive on my EFI engine for years, your engine shops correct at some rpms, under some conditions ,the gear drive does, on occasion make the knock sensors crazy, but that doesn,t necessarily prevent thier use!

but youll be far better off in most cases with a cloyes true roller chain drive

[Careless]

Careless

why not post a list of parts with pictures and prices on several sites, craigslist etc.

 

Thanks for the links, grumpy. I'll get him to make a post that he can just cut and paste into various forums.

 

sorry to intrude.

[rsicard]

rsicard

 

 

Ive run a jackson QUITE gear drive on my EFI engine for years, your engine shops correct, at some rpms, under some conditions ,the gear drive does, on occasion make the knock sensors crazy, but that doesn,t necessarily prevent thier use!

but youll be far better off in most cases with a cloyes true roller chain drive

Grumpyvette: Trying to interpret the phrase "your engine shops correct at some rpms". Apparently the QUITE Jackson Gear Drive does not always affect the EFI Knock sensor. I am building a 1 piece rear main seal block and the camshaft sensor is the distributor without the high tension side. Really don't want to run a chain as it will develope slack and then cause scatter in the cam sensor timing. I guess I would rather put up with the occasional knock sensor going crazy and retarding the ignition timing.

Edited April 29, 2009 by grumpyvette