327-365 hp pump gas?

i have a 68 327 built with 327-365 trw small dome pistons and 64cc fuelly heads, that have been ported and chambers unshrouded and polished, probably in the 67cc range...and fel-pro .039 head gaskets.holly strip dominator intake and carter 625cfm afb i dont think it will really be 11:1 probably more like 10.25-10.50, right now it has a comp cams 294s solid lifter cam 248 deg @ .050 and i forget the lobe seperation i think 110? think i'll get away with pump gas?? or step up to a bigger cam to bleed more pressure off??? its going into a 55 chevy straight axle g***er with a t-10 3.44 first gear and an olds posi right now its got 5.14's but i'll be swapping to 3.64 gears hope it wont lug to bad down low... figure the car should be around 3000pds or lighter... worse comes to worse i got a 350 smogger i can throw a lumpy cam in just to get the sound... but i'd rather use the 327...and shoot for low 12's high 11's and besides i already have it sitting on the stand collecting dust/rust thanks for any input

 

FWIW you could go HERE and use the dynamic compression ratio calculator. I found that after reading about it in a mag. The article said to keep a carbbed engine 8:1 Dynamic or less (they specified with aluminum heads AND EFI you could go to 9:1 on 'pump gas', I want to say it was Hot Rod in one of their articles on maximum effort on pump gas)

 

I have the basic same engine in my 64 vette, it is a mild ported fuelie with a cam motion 248 in 254 ex 110 lobe separation around .560 lift. I still run the stock rochester fuel unit, timing 40 total, 3.73 gear. I have no problems running it on 93 oct. With street tires capped up it ran 12.80 @ 108 with 2.0 60 foot times. It does run rich which also helps with any potential detenation.

 

thanks for the quick replies i'll deffinetly try that dynamic compression calculator... good to see someone running a similar combo in the 12's aero your from n.e.p.a.?? my parents are in ****ord pa and i'm across the river from honesdale pa in narrowsburg ny where do you run island in jersey??

 

tried the dynamic compression calculator but not sure about the cam input spec it says cam timing @.050 +15 deg?? mine is 50* abdc @.050 it would be 65* if i added 15* to the .050 cam specs wich would put me in the 8.1:1 dynamic compression ball park if i dont add the 15* its more like 9:1 hmm... we'll see i guess...

 

Well, at least it sounds like you're in the ballpark somewhere. Good luck.

 

I ran that exact cam in a 327 with 9.7 /1 comp on 89 pump gas and 44* total timing thats a big cam and even with 3.73 rear and M22 it was lazy taking off but man did it go after 3500
I think you'll probably be ok on 93 and maybe a bit less timing

 

A lot depends on the load imposed on the pistons, ie. weight of vehicle, gear ratios (******, differential), rate of acceleration. The harder it is for the combusting fuel to push down the piston, the higher the combustion pressure and temperature. Polished piston tops, valve heads and combustion chambers (all sharp edges removed) all contribute to the reduction of detonation.
As well, I've found that you cannot determine by "published" data what your static compression ratio really is! I measured up a so-called 10:1 flattop .030" ,64cc chambered sbc to be actually a 9.2:1 engine. The cast pistons were .055" below deck, six of the eight combustion chambers were 65cc's (I finessed the other two chambers to 65cc's) and then installed a steel shim headgasket to end up with an actual measured 9.2:1 CR. Comp Cams Extreme #12-242-2 tilting 1.6 rockers opens the intakes to .501" and the exhausts to .512" wth a LS of 110. 1800 stall on a TH350 with a 3.05 rear gear. Stock pre-HEI dissy with Pertronics conversion running 8 initial and 36 total runs the 3200# Chebby on 92 octane through an Edelbrock carb. It was done this way to be a highway cruiser and still behave itself around town.
Only way to know what you have is to measure (cc) everything in the combustion area and then do your calculations. Also, your cooling system NEEDS to be working at its best. There is also the chance that you could get a tankfull of "bad" fuel - in which case have some octane boost handy. It does happen! Even with the so-called "good" nationally recognised gasolines!

 

I'm living proof of that (bad gas cost me an engine, national brand too). It gave no warning though, so octane boost wouldn't have helped.

 

Put that same set together with the 327/365 cam once. Ran fine on premium. It was in a 79 RS Camaro, so 3400 lbs, auto, no stall, 3.?? gears (not as low as 3.55 or 3.73)

 

I'm located in Mooretown [ 15 miles nothwest of Dallas Pa.]. I ran at Nu Media; this is located about 10 miles south of Catawissa. They run test and tune on fridays starting at 5 p.m. weather permitting.

 

Do you have any part numbers, like the TRW pistons, which ones L2166?? or are the H something. There were lots of lots of different domed pistons are they standard bore size or over size? Which heads do you have what is the casting number and valve sizes. What springs on the valves?

 

JessieJames88
Your combination sounds like fun.
We built a similar engine for a customer and dyno'd several intakes.
That Strip Dominator is a large manifold for your engine.
Holley made 2 different Strip Dominators. If its off the engine, look at the numbers on the bottom.
300-2 or 300-25. The -25 intake has longer runners up into the plenium and will help your smaller engine with the small heads. Both are big intakes if you don't have larger heads.
If you find a Victor Jr. or a Weiand 7530 or 7532 I think you will have better torque numbers.
My 2 cents.
Matt Shaff
Pro-Formance Specialties
1115 East Main st.
Rochester, NY 14609
585-288-1499

 

throkle rod, i dont know any part#'s off hand and i'm about 120 miles from home for work, but if i remember correctly they looked like the .125"/5.3cc dome trw's, and the heads are 1.94/1.50's and have the chambers polished and cc'ed along with port work... i did the heads about 15 years ago and cant remember the chamber volume and stuff... i have other motors that are more serious than this one but this car is meant to be fun and low buck

 

frontenginedragsters, thanks for the tip... i've had good luck with strip dominators in the past, i find em real cheap, $25 for the sbc one and an unbelievable $15 for my bbc one... for the price they cant be beat (i also run one on a 396 and i love it) but for this build my manifold choices are the strip dominator, torker2, performer, and M/T crossram. this is the stuff cluttering up my garage basicly thats what the whole motor is being built from, clutter haha the torker2 might be a little better port size but i've had no luck with it in the past...and the performer in my opinion is worse than a cast iron q-jet manifold... low end shouldnt be too much of a problem the car should end up pretty light... lexan side windows and basicly no interior i'm figuring in the 2800-3000pd range or lighter and my t-10 ratio's are pretty low 3.44 1st,2.28 2nd so even with a 3.64 rear gear it'll still be like 4.56's and a close ratio muncie we'll see i just want it to run on pump gas,i got tired of mixing and running to get cam2 for my bbc and dont want the h***le with this car i figure it wont run bad for junk i got laying around...

 

got some #'s this weekend last 3 of the head casting # are 370... had trouble finding them in my casting # book... anyone know what they are??? pistons are L2166 trw's with zero deck hight, block must have been decked at one time i guess and the intake is a 300-2 so we'll see how it runs

 

also i've been looking at the 30/30 duntov it has a really late closing point for the intake and drops my dynamic compression considerably

 

According to www.mortech.com those are Canadian heads and are 64cc. I think your going to have a hard time running that set up on the street succusfully. Without some octane booster. I am running flat tops and a similar set up with .040 over size pistons it gets really hot which has alott to do with the timing I have to run which generates alot of heat but I am in Texas and it's a little warmer here than New York. I would count on the booster and it won't make the wrist pins rattle when you shut the motor. The L2166 iare 11.5 compresion pistons. I do like the sound of the 30/30 duntov solid lifter cam.I've had a couple. It takes some practice to get the valves set. Have fun, a set of fenderwell headers will do wanders for the set up you are contemplating along with a high rise manifold single plane and a 750cfm carb.

 

we ran the 11.5 trw domes with 58 cc heads and lots of gasket, I think it was 300+ duration cam, and it ran on premium ok, fairly heavy car.

 

i'm planning on running fenderwells if i find a set cheap enough, or build my own from a couple of junk sets of ch***is headers...right now its getting ch***is headers cause thats what i got sitting around... i hate to buy another cam for it i have the comp cams 294s sitting aound... as for the carb, i have a holley 830dp(on my bbc right now) 2 carter afb 625's, and another afb not sure of the cfm?? (have to look up the numbers) and a spare N20 non adjustable 125 shot setup that i'll pobably throw on...(came off my bbc went with an adjustable)