I want to know why the hell is scat selling forged 351W cranks but using chevy 6" connecting rods. I mean I could understand if it was a stroker to need the longer rod but this is a stock 3.50" stroke crank just forged steel but yet they have chevy jorunals.

What the **** is up with that. I am beyond pissed off right now because the pistons I carefully selected to give me 9.178:1 static 7.484:1 dynamic compression isnt going to work because it uses a 0.912" pin where as the chevys use a 0.925" pin. Then I checked summit out for a stock bore 4" piston for use with a 3.50" stroke crank with a 6" rod. The biggest compression distance I could find was 1.270" which gives me a deck clearance of, get this 0.48". WTF is wrong with scat, I mean seriouslly with the 5.956" stock forged rods with a 3.50" stroke crank and the pistons I had picked out with a compression distance of 1.774" gave me a deck clearance of 0.020" and my stock 351W from 1978 is roughly set at that stock.

God knows if a oem cast crank could handle 500 - 650 hp nor if it could handle being spun up to 6,000 rpm and held there throughout the race track but I dont want to get everything built then snap a crank cause these ****tards cant offer a forged steel crank that uses the ford rods.

I just dont understand what the hell is the reasoning of using a 6" chevy rod for a forged ford crank. I also dont understand why every rotating kit is always with pistons 0.030" overbore. What if someone is buying a brand new block that isnt overbore and doesnt want to overbore it. I am to the point of just saying **** it and go bone stock on this engine build which would be totally pointless since the car is a race car.



~update~
Well I am looking at cast steel crankshafts. Eagle`s description on summit`s site says that they can handle mild engines and I dont think a 9.178:1 compression 351W with Man-O-War 2.02"/1.60" heads with a 230*/236* @ 0.050" 0.513"/0.526" lift, 112* LSA camshaft to be a hot engine. I consider it to be mild but with the 1000 cfm edelbrock Pro-flo2 multiport fuel injection, comp cam`s program camquest is estimating the following

with out of the box Windsor Sr 2.02"/1.60" valves
467.5 HP @ 5500 RPM
475.9 Trq @ 4500 RPM

Same heads but ported like the 2005 Engine Masters Windsor Sr heads but maintaining 2.02" intake over 2.08" valve
602.3 HP @ 6500 RPM
524.2 Trq @ 5500 RPM

Now I changed my mind on heads cause I am going with the Man-O-War aluminum windsor heads. Still 200cc intake port volume and 2.02"/1.60" valves as in the Windsor Sr heads, same program gave me this figure

out of the box Man-O-War 18* Aluminum heads 2.02"/1.60" valves
524.2 HP @ 6000 RPM
494.7 Trq @ 5000 RPM

Not sure what the power output would be with these heads match ported to the single plane highrise manifold as well as the power output with the heads polished up abit. In the end I need a crankshaft that can handle the power of the engine as well as prolonged mid - high rpm speed without flying apart. The assembly will be blueprinted and balanced so it should run smooth up to 6,000 rpm (wouldnt take it past 6,500 with hyd rollers).

 

Rusty, I always love your posts. Always interesting. ( And I could just feel your rage).

Are the chebby rod bearings smaller? The rod magazines had a lot of discussion for a while about using smaller rod bearings for some reason or another. I think that a lot of the discussion was in Circle Track.


Anyway, good luck with your engine.

 

I honestly dont know why they want chevy rod bearings. They are smaller just like the piston pins are larger. Only thing I can figure out is to gain a better rod ratio. 5.956" ford rods with a 3 1/2" stroke is 1.70:1 rod ratio. With the 6" chevy rod it improves it to 1.71:1. Honestly I dont see where a 0.01:1 improvement in rod ratio will help reduce piston loading when automakers seek 1.70:1 as their ideal rod ratio. Its just added costs.

But I had a goal of 500 HP out of this engine, this guy on the forum that I am on for the kit I want to build is saying that a more realistic power figure is 420 - 440 hp. Now I just dont see how I could be making less power with a 351W than I am with my chevy 283 with ported OEM heads and a 650 holley double pumper. Yes compression is very high on the 283 but still 495hp out of the 283 with OEM heads and a 650 holley carb is nice but to get just 420 - 440 out of a 351 with world products Man-O-War aluminum heads which have huge 200cc intake port volume and huge 2.02"/1.60" valves and moves almost 250 CFM at 0.500" lift intake with a edelbrock single plane highrise multiport EFI moving 1000 cfm is just pitiful.

I am thinking if I am just going to be making 440hp max with this setup why am is my price tag up near $6,000 when I can get a stroker 408 making 520 hp for $7,000. Downside is I wouldnt have pieced it together myself, it would have a shotty rod ratio of near 1.4:1 - 1.5:1 with higher piston side loading than the oem 351W.

So I am looking at the cast steel cranks now. They use the oem ford rods and I am waiting for a reply from eagle on the power their cast steel cranks can handle. If they can handle 500hp (their cast steel stroker crank can handle 520hp) then I should be safe with that.

Only thing I am having to think about is do I need 500 hp in such a light car. I was told I need 500 hp to maintain 150 mph on a road course track but I dont see why I would when the car is the same weight as the orignals it replicates which used a 385 hp 289 @ 6750 rpm and was able to push the car up to the 180`s with a 4spd and 3.09:1 axle ratio. Given I am going to be running a 5spd TKO600 with 0.62:1 OD and 3.55:1 gears but still I should be able to hit 150 even with 400 HP. I just dont know only thing I do know is that I am starting to second guess comp cam`s recomendation of taking the 2000-6000rpm camshaft I was looking at and recomending a custom grind using the same camshaft just go from a 110* LSA to a 112* LSA. I have listened to the 112* LSA camshafts on youtube and while they do sound good I just think the 110* LSA would be more fitting.

This is the video I saw with a 231*/236* duration 112 LSA camshaft (specs on the one comp adjusted is 230/236)
YouTube - TSP 231/236 112 LSA Cam, WCCH L92 Heads, Kooks Exhaust

Given it does sound good but for some reason I just like this sounding idle better, this sounding idle sounds more like what a race car should have and the kit is a replica of the daytona coupe FIA GT class winners in 64/65.

YouTube - 1969 Chevelle with Spin Tech mufflers and custom exhaust

Given the last cam is a comp cams solid roller cam, 248/254 with .616/.622 lift on a 110 LSA, the difference in duration between that one and the 230/236 shouldnt effect the idle qualilty or the exhaust sound the LSA does that from my understanding.



~Update~

Guy responded in other forum with a link to a ford magazine forum they talked about giving a email to this guy over at adperformance.com that they know the scat cranks inside and out. He talked alot of people out of the forged cranks in their 408 strokers and went with the cast steel cranks. He told the guys that the block would go before the cast steel 9000 series scat crank would go. He even said that their good up to 700 hp. Well hell if thats the case then I will use it in this build as well. I dont ever plan to go over 600 hp out of this engine but I think 500 would be the max I would want in a car that only weighs 2,500 lbs.

 

WAG on Chevy rods--they are easily available and cheap. Smaller bearing sizes means lower bearing surface speed, which means less friction etc.

Same deal on 385 series strokers, they use the BBC rod with smaller bearings.

As for piston pin size, perhaps they are thinking custom pistons, beats me...

 

I read that last night on bearing speed in my ford windsor performance book. It talked bout higher bearing speeds results in higher oil temperature. Considering I am going to run an oil cooler with synthetic oil I dont think I should have to worry about excessive oil heat.

Chart was listing 4712 feet per min bearing speed for a 3" main 351W @ 6,000 rpm. Considering I wont be running at a constant 6,000 rpm the max would be 4712.

Only thing that I cant get a clear answer on is the high volume oil pumps. Half tell me I might need it for running a remote mount oil filter and a oil cooler since theres so much more oil passages it has to go through. But others says not to that it puts excessive load on the dist shaft and can wear out the roller cam dist gear quickly. Plus if I need a high volume oil pump I would hate to get the engine built then have to pull it just to put a high volume oil pump in. Like wise I would hate to do that and then wear out dist gears every so many thousand miles.