Just check out the second thread stuck to the top of this section. 400/430/455 Block ID, Prep and Oiling mods Devon
I am surprised you chose the higher compression. I really like "the Sneaky 500", JW built engine and concept, because of its "daily" use capabilities and since you like to cruise it seems like a perfect fit. Wont your engine make power at a higher rpm than you will see on the street, or better yet, want to see? (Bigger cam, more converter, hard shifting..etc)Maybe I read more into your purpose than I should have. No doubt it will be fast!
Gary Correct me if I'm reading you wrong. The beauty of the "The Sneeky 500" engine was that, using a cam with a late closing intake valve would allow a high static compression ratio and still make good power with a DCR as low as 6.5 In Jim's evaluation he points out that even though this engine ran well with a very low DCR, it would certainly benefit from a higher SCR. Jim used a cam with a 118* lobe separation angle that didn't close the valve on the seat till 86* ABDC. That means the static compression ratio could be as high as 12:1 with DCR of 7.75 and still be able to run on pump gas with room to spare. Here is a quote from Jim from that thread. I just didn't want anyone to miss where Jim was going with this project. I hope he gets a chance to finish it someday. In an effort to get good quench by having a near zero piston to deck, you end up with compression ratios near 11:1 with most pistons and 64cc chambers. This is when it is important to chose the right cam to give the needed dynamic compression ratio. This is a long way around just to say I like what Dave is doing. Paul
Paul, you are correct. I was thinking the "Sneaky" engine build was the lower compression build. I can't find that thread but I believe he built it for a site member. My mistake.
I think i will go with TA's heads from geisslers with some porting See what kind of $ i can come up with . This is going to be a slw prossess So i want it right still looking at cams and heads but TA are what i would like if the $ is there . Not sure if i want to even look at the edelbrock heads to much to accessories to add , rockers , pushrods ect
Dave The TA aluminum heads are the logical choice even from a dollar value prospective. Good decision! The TA heads usually come with around 64cc chambers. Your pistons need to be close to zero deck to take advantage of the inverted dome design for excellent quench. The piston and rod combination you have gives you a .025 piston to deck clearance before machining the deck which is nice because the deck doesn't lose very much material and the intake manifold runners will be easier to match to the intake ports. If you machine the deck for .005 clearance, with a 19cc piston dish, the static compression ratio will be right at 11:1 In order to have a dynamic compression ratio of 8:1 or less so you can run on pump gas, the cam selection must be so the intake valve doesn't close on the seat before 76* ABDC. (using the advertised duration to calculate valve closing) The TA 413 installed at its normal 4* advanced position closes the intake at 72* ABDC. It would have to be installed straight up to meet the criteria. A little larger cam will be needed but you would like to keep the overlap at a minimum for drivability and gas mileage. If you use a single duration cam where the exhaust duration is the same as the intake duration the overlap is decreased. In this case the Stage 2 heads that have the better exhaust port and do not require the split duration camshafts are a better match. The Stage 2 heads cost about the same as the Stage 1. The TA 290 has a single duration profile of 238/238 and even though it has 4 more degrees of intake duration than the 413, the overlap is about the same. You can have TA grind this cam on a 116* lobe center which will close the intake valve 77* ABDC. This will give you a 7.9 DCR for pump gas and a 6* overlap (7* less than the 413) for a slightly rough idle and decent drivability. This is just one possibility If you want to follow what Jim Weise did in the following thread, have the TA290H ground on a 118 lobe center. The DCR will be only 7.7 and the engine will idle like it has a TA212 in it with a 2* overlap. http://www.v8buick.com/showthread.php?t=183826&highlight=sneaky+500 The difference will be with your higher SCR and the Stage 2 heads the horsepower should be a little more. The only drawback with the Stage 2 heads is TA Performance appears to only have 2" primary tube headers to fit them. If a dual plane intake manifold is being used it would be better to have 1 7/8" tube headers to match for low end torque. I'm hoping others will share their point of view on this project. Paul
Paul Thank You for the info Looks like i got some things to consider . Cam will be most likely my next on the list . then the Heads I am looking at the TA stage 1 level 2 heads for gesslers not to over kill for my application ..Do not think the stage 2 are for me . I do already have 2 " primaries but not for stg2 heads with 3 1/2 collectors in the set of KB Pulse Headers in to a 3" x pipe system on the car now. they might be hurtting me some with my present combo . Then it all goses off to My Builder Mike FiGG in Ft Lauterdale . Sharp Guy , He will understand this a whole lot better than i ever could . But the way you explained it to me is understadable I get it ! Thanks for the Advice Very much apreciated with any luck and help from the Board I will only have to do this One time .and be happy with it . Thanks Dave
Dave I'm curious. If the Gessler Stage 1 and Stage 2 level 2 heads cost the same, and the Stage 2 heads will be more streetable with your 11:1 compression engine because it gets rid of the exhaust gas better allowing you to have a cam with less overlap for better gas mileage and smoother running at low rpm, then why choose the Stage 1 heads? Paul
Probably because he already has headers for the non-Stage 2 heads. Same reason I made the same decision. Devon
Yes Devon thats the reason . I Know the heads are the same $ with the stage 2 heads ,plus new headers .. trying to use some of what i have and build on it. I see your point paul " The Stage 2 exhaust port flows a tremendous amount, making the Stage 2 head a better choice for a race engine " were as the Stage 1 Level 2 are "Recommended for a very cost effective increase in flow. Bowl blending helps make the heads more efficient without enlarging port volumes, which helps maintain port velocity for milder car/engine combinations" This Motor will see the track But not that much She is a Driver / Cruiser If i was going to go racing all the time Maybe I would go that route and continue upgrading from there But not my Plan. Dave
Jim Thanks for your reply. I appreciate the time you take to post the details of your many projects. I have learned a lot. Paul
No i want to thank everyone Jim, Paul , Devon For some insite I now have a good idea of what i need to do. a higher compression motor 10.0 -11.5 static compression and the right cam degreed to close the intake around 74* abdc atempt to get dynamic comp. daround 8:1 like in Jims build Only with Aluminum Heads sound right to you all? Jim were or are there any areas i need to pay close attention to that may give me issues? Dave
OK its been along time but its happening Old Thread but the Block is done ready to install pistons and rods what should my main and rods be set at my guy says .0025-.0030 ? have decided to go with Edelbrock heads Much more cost efective . I was able to do new heads complete , comp ultra po magnum roller rockers and head bolt kit for less than what most want for just the heads ,just need to get correct lenght pus rods . Now to decide on the cam lob center lift duration ? Ta 290-H or 298-H ,, 288-92-H after all looking at a 10-1 to 10.25 -1 gestamate 68 cc heads will check when i get them, all oil mods done , or would a milder cam work best , it will have to be custom a grind , I all so have both TA SP1 and a Edelbrock performer thinking SP1 with my q jet or the 950 Demon i have on it now Its time to hamer down need some expert advice here on my combo I dont want to do this again! Thanks For listening and thanks for advise in advance Dave
Dave A few questions first. Did you zero deck the pistons? Do you need enough manifold vacuum to operate power brakes? Paul
no on the 0 deck squareed off deck the 10-1 pistons we are going to try to keep comp were i can run pump gas , line hone/bore yes i need power brakes
On paper the pistons are .025" in the hole for a 10.2 compression ratio. You will need to measure to see what the piston to deck clearance really is. Since you are using the Edelbrock head you will make more power if the exhaust duration is more than the intake duration. In order to have vacuum for power brakes the overlap should not be much more than 10* Something like the TA 413 cam would work. The next step down would be the 288-94 You already have 1.6 roller rockers so I would strongly recommend a roller cam. You can have less duration with more lift for a wider power band. Less overlap improves street manners and better manifold vacuum. And the most important reason is No Cam Break-in procedure and far less chance of lobe failure over time. Paul
