Author
|
Topic: 351w questions
|
clay37355 Journeyman Posts: 5 From: Manchester, TN US Registered: Aug 2001
|
posted 08-16-2001 01:32 AM
Questions, Questions, QuestionsOk here goes. I am working on a '69 Mustang. I have pulled the 302 out and I am planning on putting in a 351w. I am on a tight budget, so I have been buying most of my parts used. I have already obtained a set of older style TFS heads 2.08 In. 1.65 Ex. The heads have been Ported to flow 305 cfm on Intake at .700 ( at least that is what the guy told me) The Cam I bought is a solid roller with .640 in lift and 300 degrees duration on both sides. I have the Comp cams solid roller lifters (the ones with the link bars). The Block is a '83 out of a F250 Question 1: I would like to try to find a '74 or older Block because of the beefier main webbing. Will I be able to use the cam and lifters with the older block? I have heard the the older blocks require a "small base circle grind cam" (whatever that is) And i also heard that the small base circle cam was only required if you were going to use the stock type lifters and hold down. Question 2: What Ratio Rocker arms would be best? Question 3: I am wanting to stroke the 351. How much should i go? At first I was worried about going to the 393 because of piston speed. I will be reaching peak horsepower about 6500-7200 (says Desktop Dyno) I have read on the internet where alot of 393 are safely pulling 7000-7500. I dont want to go with the 408 because of the small compression height of the pistons. so it is a toss up between 393 and 377. Question 4: I would like to use the stock Harmonic Balancer. I am going to have the rotating assy. balanced. At that high of rpms would it be a must to go with a aftermarket Harmonic Balancer, or would i be safe with a stock type. Question 5: How much Horsepower can a stock 351w block hold up to with a main stud girdle? I have several other questions but I guess I better keep this post from getting to long. Thanks for any help and suggestions.
IP: Logged |
steve'66 Gearhead Posts: 5659 From: Sonoma,CA,USA Registered: Mar 2000
|
posted 08-31-2001 01:17 PM
Clay,How'd we miss this post? Sorry about that, and welcome to M&M! Wow, too many questions all at once... Anyway if you want to turn a stroker that high you'll need great rods and light forged pistons. Your TFS heads should work fine. The stock harmonic balancer should be replaced. Crane Gold rockers work for us. A friend's 408W dyno'd at 530hp at the flywheel, naturally aspirated. It's been holding up to an extra 150 shot of nitrous also. Whew, hope I didn't miss anything..... SteveW
IP: Logged |
kid vishus Gearhead Posts: 3894 From: middle of NC Registered: Oct 2000
|
posted 08-31-2001 04:37 PM
Welcome to M&M Clay First of all, if you plan on dragracing it at all, the stock balancer must go. Any motor with a mechanical roller camshaft must have a SFI approved dampner. Besides, the stock one is not a good piece for any high output motor. I like the Crower stainless rocker arms. I would run the stock ratio, 1.6. By increasing the cubic inches of the motor, you lower the operating range of the camshaft. So a cam that might make power up to 7500 in a 351 cubic inch motor, might only pull to 6800 in a 400 inch motor. I have been told, that a properly prepared stock block can handle around 630 HP. But that involves way more than just a main girdle, stuff that engine builder wouldn't share. And as a last note, Desktop Dyno exagerates the horspower and rpm numbers, so take it as the unproven numbers it is. It claims my motor with the cam I am running should make power up to 8500, well, it doesnt. About 7500 is where it stops making power. (I twisted it to 8000 once, it went slower) (I really 69 mustangs )
IP: Logged |
Dave_C Gearhead Posts: 666 From: Gadsden, Al Registered: Aug 99
|
posted 08-31-2001 05:06 PM
Been there, done most of that.I have a 69 Fastback with a 383W. 1. The 74 and older block are better, according to rumor, but I have never seen it proven. Mine is a 69 block. I did compare mine to a buddie's 2 bolt Sportsman block and it appeared to be the same in the webbing area. The cam will be fine, solid rollers require nothing top be used in any year block. The reduced base circle cams are for a conversion to a hyd roller cam. 2. 1.6 rockers, that cam will like the rpm, so consider a stud girdle while you are at it. 3. My 383 has a 4.060 bore X 3.70 stroke, it would have been a 377 if it was .030 over. I have had very good luck with it, but I built it before any of the new cheaper aftermarket cranks were available. Then it was either an $1800 forged crank or offset grind a stock one ($300, $150 to offset, $150 to widen journals for SBC rods) 4. Toss the stock balancer. Got a buddy with a dent in the fender from the underside where one came apart at 6500 rpm I run a Summit brand damper, not too $$ at $255 and it's the same part as sold by Ford Racing. These are made in Australia by one company and sold under several brands. 5. I have a DSS style main girdle. I turn it to 7000 rpm, no problems with cap walk. HP is ?? I have a dyno program that estimates 580 hp at the crank. Don't know how far off the mark that is, but the same program has predicted my best ET to within .02 seconds. 6. I'll add this one. You said older style TFS heads. Are you talking Twisted Wedge or Street Heat? If you have the Street Heats heads we have a problem. You have two header choices. The ones from Unobtainium Corp or the ones from Cubic Dollars Inc. The Street Heats have an exhaust port that is raised .500" from stock. There are NO off the shelf headers for these heads in an early Mustang. Custom is the only choice. Saw a set of used ones a while back in a web classified for a 67-69 Cougar with these heads. Prob would fit your car. They were $800 used, uncoated. I would love to have had these heads, but went with the Windsor Sr heads instead. Headers are off the shelf Hooker Super Comp # 6208. If you have the TW heads, you are ok on headers, but be aware that you will ned custom pistons for the altered valve locations when you run a cam of that size. Oh, and welcome to the board. Let me know if I can help. I don't live that far away. NE Alabama. My car: http://home.earthlink.net/~racrcole/index.html Later, David Cole
IP: Logged |
clay37355 Journeyman Posts: 5 From: Manchester, TN US Registered: Aug 2001
|
posted 09-11-2001 03:17 AM
Thanks for the reply guys. I was begining to wonder why noboby liked me . I have Found a '72 351w block. The main webbing is impressive compared to the '87 block i had. I bought the whole motor for $100, and found out it had the D00E heads on it. If any one is interested they are for sell in the Classified section. Dave_C. Im not 100% sure about the heads. I have to do some more research on them. I know they are not the twisted wedge. And I dont beleive they are street heat, because the exhaust ports seem to be standared height. The heads have "Steinburg" stamped on the end of the heads. Also, I would like to take my bore out to 60 over. I figured with the 2.08 valved head, the bigger the bore the less shrouding would occur. I placed the heads on a bare block. I Flipped it over and looked through one of the cylinders. It suprised me how close the valve and edge of the combustion chamber was to the cylinder wall. have you had any problems with the 60 over? some have told me it would be pushing it. What kind of SBC rods are you useing? Thanks guys. I like getting advice from people who have actually done this stuff like you all instead of people who think they know it all but really have no experience.
IP: Logged |
Moneymaker Administrator Posts: 18704 From: Lyons, IL, USA Registered: May 99
|
posted 09-11-2001 12:14 PM
Welcome to M&M Clay ! I have not been around much as our racing season is in full swing. Earlier blocks are indeed stronger. DSS girdles are useless and a waste of money. (PROVEN FACT) Good harware and a precision machined block is all you really need for stability and longevity. Crane or FRPP aluminum or Crower or Comp stainless rockers are all good as long as you use a stud girdle. T&D or Jessel shaft sylstems are far superior. The only time you would need a small base circle cam is with a monster stroker kit where the rods could actually come in contact with the camshaft. Good luck, sounds like you are on the right track. ------------------ Alex Denysenko Co-Administrator and Moderator NHRA/IHRA/SRA member NHRA and IHRA SS/LA National Record Holder '00 & '01 Fleet of FoMoCo products Moneymaker Bio US Class Nationals link
IP: Logged |
albatross Journeyman Posts: 25 From: NZ Registered: Sep 2001
|
posted 09-17-2001 03:23 AM
Moneymaker, Seems to be a lot more aftermarket stuff around for the windsor but I live downunder and can easily pick up a bare 4 bolt mains 351 Cleveland block off a wrecker for around $200 USD. How hard is it to find a windsor block thats similar?David
IP: Logged |
JAAZZY Gearhead Posts: 745 From: Bay Area, CA Registered: Apr 2001
|
posted 09-17-2001 07:40 PM
Dave_C,Just wanted to let you know that I have the Street Heat Heads and I able to buy a set of full length headers from JBA for a 64/66 with 351W conversion. It took quite a bit of removing dinging and reinstalling but they worked fine. JBA doesn't make them anymore but I wonder if you could do the same thing with the Hookers...
IP: Logged | |