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Author Topic:   bowties and machine work
ryan
Member
posted November 06, 2002 09:58 PM
I have found a set of 034 bowties for sale with a .100 angle mill with 2.05/ 1.6 titanium valves. They would be in a .550 lift 350 .30 over stock stroke street stock motor.(say that 3 time fast!)I was wondering if there would be any clearnce issues with either the block or pistons. Also does anyone have a rough estimate of how many cc's they would come out to be. thanks


KPLugnut
Member
posted November 07, 2002 08:25 AM
Your valve to piston clearance won't be enough without good racing pistons that have deeper-than-stock valve pockets.
The heads (assuming they ONLY had .100" taken off) should be around 54cc or so.
It's impossible to give an exact answer because there is no way of telling how sunk the valves are, or if any chamber work had to be done for unshrouding those big intake valves, which would throw off the starting size of the chamber before milling.
You'll also have to watch how the intake fits on the heads since angle milling sometimes also requires re-cutting the intake side of the heads to correct the angle. Which, then, requires special intake gaskets as well.

Hope that helps.

KPLugnut

[This message has been edited by KPLugnut (edited November 07, 2002).]

ryan
Member
posted November 07, 2002 04:32 PM
What kind of pistons would you recommend. Rules say no forged pistons. The intake side has been corrected so what type of intake gasket would I need. How much clearance would you recommend. Thanks again kp
p.s. I'm on a tight budget
Anybody else have any comments?

[This message has been edited by ryan (edited November 07, 2002).]

dirtracer14
Member
posted November 07, 2002 05:12 PM
Just somthing to add...dont just check the depth of the valve to piston, also check the diamiter of the valve to piston. When using street type pistons they dont have enough room on the outside of the releaf for the 2.05 just somthing to double check.


Monster
Member
posted November 07, 2002 06:18 PM
I don't know, man. If you are on a tight budget, and are not a VERY serious amateur engine builder, these heads don't seem like a good fit. The warnings about valve pocket depth and location are valid ones, and sometimes it can take complicated assembly/milling setups, or multiple operations to get them right. Titanium valves are another hurdle. They CAN be fairly reliable, but if they wear just a little, they can chew a set of guides up REAL quick. They also don't bend like a stainless valve will, they...break..Kaboom! There is a learning curve involved. You'll need a thicker intake gasket, up to .125. Don't remember the #'s, but Felpro makes them in several thicknesses and port size, as do others. Head bolt and block dowel pin issues can also arise.


KPLugnut
Member
posted November 07, 2002 07:47 PM
I have to agree 100% with the above post here. The thing that just bit your project in the rear is the rule prohibiting the use of "forged pistons". Even if you go with hypereutectic pistons (which are usually legal in a class like that but, honestly, are also forged), they won't have the properly sized valve pockets. Both the depth and the diameter will need to be changed, and that can be a complex machining process for the average guy to attempt.
Monster is right, the thicker Felpro or other brand intake gaskets will be needed, too.
I think one of the main reasons they have piston rules like that is to limit racers from doing things like this above the pistons.
It's true, as well, about the titanium valves, too. for the average weekend warrior, they're prone to do exactly what was explained above. And a single replacement valve is seriously more costly, too. One other thing about them is usually when you see a used set of titanium's for sale, it's because they are already past their cycle of dependability.

Just hoping to get ya going in the most dependable way.

KPLugnut

ryan
Member
posted November 08, 2002 09:59 PM
Well s.c.r.e.w it. Seems every time I try to go forward I go two steps back. Might just get some double humps from the machine shop and take my place in the middle of the pack.
I know one thing for sure. I need more PONIES!! I can beat some people through the corner but down the straightaway they pull away.Does anyone have any advice on what I should change in the motor department? Rules are in no particular order
11 to 1 max compression, no forged pistons, no strokers, crank must match block, 360 cu in max, no roller rockers, no lift rule any stock head(can be ported and milled) no vortec type heads only other heads allowed are the bowties(no porting) 034's , 4 barrel quad or holley 4412, performer and torker II are the only aluminum intakes allowed, headers allowed. Thats about it I think. Right now at 6300 rpms I run torker II intake, modified quadrajet, schoenfeld headers, hi-perf hei, solid cam .504 lift 106 lobe that will probally be out to put an ultradyne cam in.Currently 993 heads (double humps became doorstops) Any suggestions on how to get more power. Sorry for the length!


ryan
Member
posted November 08, 2002 10:03 PM
Oh yeah one more thing. Thank you. This place has saved my so much time and not to mention $money$ there would be things I would have tried if I hadn't read other people doing those things with no luck.
Thanks again.


KPLugnut
Member
posted November 09, 2002 06:01 AM
Ryan,
So much info to talk about....perhaps if you like, call me and we'll chat.
607-277-6462 (EST, weekdays after 5pm or weekends, except when I'm logged on from home, lol!) or..
weekdays: 607-266-3129

We'll do our best...

Dayton Umholtz, owner
Kinetic Performance


66jj
Member
posted November 09, 2002 12:11 PM
i have ran the same cam youve been running,(256-264@.050) in my opinion its dead at 6200 rpm, i love the tight lash cams in speedway, they make lots of power, i have tried them all, i started big and got smaller each time, the smaller ones were better for your rpm and parts..



Eljojo
Member
posted November 09, 2002 08:10 PM
66jj is ABSOLUTLY correct! The one single most important piece of any race engine is the camshaft. Don't be deterred from ALL Bowtie heads, just ones that have been "tweeked" as much as the set you described were. Look at your rulebook and then look at your pocketbook. There's some middle ground there. Run the domes, Spend the $ for a Dragonslayer and have it turned to Honda journals. Go with long rods. Run solid lift cam with roller tip rocker. Have the Q-jet worked.Did I mention go to sbc 400? Loghten the clutch/flywheel. READ YOUR RULEBOOK, all the while keep thinking "what did they miss that I don't see?" I've personally found great pleasure in locating loopholes! The big one in my local paved tracks rules was "must run stock heads" See the word "cast iron" in there anywhere? *grin*


ryan
Member
posted November 09, 2002 11:25 PM
Eljojo Must have forgot to mention the flat top only rule cant run 400's 360 cu in max also no rollers allowed. Kp I might have to take you up on that offer. I know heads and cams play a huge part in making your power. The cam I was going to change to is one that was recomended by a guy I pit next to and has helped me out a ton this year. He has had 30 some top 5's the past 3 years and has been in the championship hunt the past 2 so I know he has it figured out. I have been getting better and better but I want to make the A more than I have been. I'll get it figured out one way or another lol thanks guys


Scoot
Member
posted November 10, 2002 05:55 PM
Ryan, I'll tell you what I ran this year just to give some ideas of what worked for me. This was in a Hobby car running against Super Stocks, finished 5th in points. Holley 4412 from KP, Cam from Charles at Camcraft, Hyper pistons, stock crank and rods, double hump heads ported, polished and milled. Block was zero decked, bowtie highrise cast iron intake. Balanced the motor and used Clevite bearings. The only thing different I will do for next year is get the lightest weight flywheel clutch combo allowed by rules. That was the only place those guys were getting me. And for anyone else out there reading this, DO NOT BUY FIBERGLASS LEAFS. They seem to work fine, but they wont take the abuse of the track, both mine are split. Hitting the wall and having people hit me didnt help.

------------------
Scoot
Smith Racing Team
870-365-5989


ryan
Member
posted November 13, 2002 08:44 PM
anyone else??


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