been talking to mike p about some specs and limits of my engine but i decided to make it public so everyone else could get the good information ive been getting. on to what im here for almost have all the parts for my shortblock ive decided to run. (waiting to be shipped) top end is negotiable to the wallet. stock crank oil holes chamfered ground for pontiac rods. 73 block with all oil mods in jims sticky. c.a.t. h beam pontiac rods. wiseco flat top pistons. wiseco rings. going to have the block decked to around .010 or .005 dont want crazy fitment problems. if i only have to cut like .020 off i will 0 deck it. will have the block half filled. i will run around 12-1ish compression. will be measured when i get all the specs. might run the 308s i have or get something custom ground so i dont have to use expensive rockers. unsure yet. no girdles all i have is stock oil pan and i wont be upgrading unless someone has a good deal on one. im not afraid to get the welder out and add a baffle though. good ta cam bearings. wanting to spin to around 6200-6400 sound like an ok idea guys? what gears would be best to hit the traps at 6400 29 tire and th 400? this is for an all out drag race build i probably wont be done with until the fall. by that time i hope to have the suncoupe running by then. thanks for any help guys.
if funds allow i will be getting a something around a 4000 stall from jim w. a 9.5 converter. not sure of slippage. im not much of a converter guru. im not sure of what mph i should be at that rpm. im hoping to get into the 10s with good heads. depending if i can afford to run the 308s with rollers. if not i will have a converter probably around 3500 with a custom cam something a little smaller than ta's 510. only reason to run the 308s is because i already have it. with ta stg 1 heads ported from ta. say. flowing 310/180. spx and 1050 dommie what kind of mph might i be able to get with the 308s?
A 4.56 gear with a 29 inch tire would put you at about 6400 RPM at 115 MPH in the quarter. That is factoring in some converter slip. I am guessing you would in the high 11s or low 12s so I used 115 MPH as a base for the calculations. I would rather use a 4.11 gear with that 29 inch tire, it would put you at about 5800 through the traps at 115 MPH... If you plan to run deep into the 11s or high 10s then a 3.73 gear might be better.
373s would be nice since thats what i have already. some moser axles and i would be good to go. with aluminum heads and the 308s im guessing 600 hp would be pretty easy. once the chevelle is no longer my daily driver some more weight will be cut mostly door beams, back seat, dash, passenger seat. fiberglass bumpers, hood and fenders, aluminum intake and heads. maybe get it down to 3000. weighing about 3250 now without me. with iron intake and heads. maybe even take my door panels out. im running 12.8s with what i have now. im thinking high 10s low 11s no problem. with good flowing aluminum heads.
Im no expert engine builder, but seems high in the revs for no bottom end support. Are you using studs? Is the crank getting balanced?
It would likely last longer if you set the rev limiter at 6000... I am sure you could push it, but not worth the risk in my opinion. I say run it with the 3.73 and if you start running fast enough to run out of gear then consider a 3.42... I went with a 3.42 to give me enough gear to get safely in the mid 10s without revving too high.
your probably right. with a good converter gears shouldnt be as important for a high 10 sec. car. maybe keep the gears i have. run a 28x10.5 tire for now.
If your adding all the other parts spend the money for a set of studs or bolts(both ARP) and have it line boarded. I have my rev limiter set at 6K and hit it many times.
you think arp studs are needed at this point? will have the line bore checked. dont want to have to do work like that unless i have to. no buick specific shops around here. unless i want to haul it to marks guy. 5 hours.
When you have the block line board, you move the cranks center line closer to the cam. It is usually only 0.002 inches or so if doing so while there is no damage from a spun bearing. It is recomended if you change from the factory bolts. Most any mechine shops can do this.
i know what line boreing is i was just messing with you because of the way you spellt it. <---(dont judge me) you said line boarded lol
Again im no expert so take what I say with a grain of salt, but bearing life is a funny thing. Revs harm bearing life far and away more than load. Before you get burried deep into Max Revs, you need to be sure your heads and cam will support power at this level. Your converter, exhaust and intake need to work with it to. If youre not making power that high, then no point in revving. Maybe youre trying to protect some IP by not sharing that info, and thats fine, but if you are spending money to make power in that range, it seems kinda silly to risk it all by ignoring the bottom end. You seem to have good parts in there, why shy away from a girdle? Doesnt have to be a full block girdle, even the main cap girdle is a big help. IMO, the Buick factory main BOLTS were seriously over engineered. Switching to studs alone wont really improve anything or make it stronger. Its just nice to have so you dont fatigue the block by constantly stretching the threads. I think with the revs and cylinder pressures youre talking about, your immediate concern would be the mains walking. With 12:1 compression, im going to take a wild guess that this car will be a race only, or mostly race car. At 6k regularly youre gambling. The factory rev limit was 4500, and unless you do some major work to your bottom end, I think past 5500 regularly you are pushing your luck.
A "race only car" definitely, definitely needs a higher volume/deep sump oil pan. The stock pan with a baffle installed is way better than no baffle at all, but for a "drag only car" why risk oil starvation with a stock pan? If you have the welder and the time to devote to it, by all means build a deeper sump and install front and rear baffles. I can't stress this enough!!! Steve
Sorry I missed that youre half filling! That should certainly help the mains a bit. I also missed that this IS an all out drag car. Like I said, Id be worried about the regular high revs on that engine with no girdle. Occasionaly 6k is probably Ok.
Doing a girdle would have about a 1500 dollar snowball effect and that will push this build probably an extra 8 months. I wouldn't mind making a deeper pan just building I pickup wouldn't be easy for me
