Hey Scott! Thumper head question

[Nathan in MI]

Okay, so I'm pretty well sold on those thumper heads you suggested for my CV, but I'm wondering how they'll affect octane requirements. Will they raise compression ratio significantly so I have to run premium, or will there be something else different about the way they flow that would necessitate it?

Thanks,
Nathan

P.S. Can't wait for SF '07!

[Lincolnmania]

i run the cheap shit mang........towny ran a 15.91 on 87 octane gas........no pinging whatsoever, and i have my timing set to 16*

[interceptor1985]

Would that work with a couple turbos. Junk yard style?

[Nathan in MI]

i run the cheap shit mang........towny ran a 15.91 on 87 octane gas........no pinging whatsoever, and i have my timing set to 16*

GOOD! Thanks, Scott!

[88grandmarq]

Compression ratio is only affected if you choose to have the heads machined or surfaced which will make the combustion chamber smaller and raise the compression ratio. non-HO motors are rated at 8.5-8.8:1 with the cast pistons and E6 cylinder heads (69cc chambers). E7 heads have a 64cc chamber so you get a slight raise in compression doing an E7 head swap.

According to Mike Shultz at Thumper, you can safely surface an E7 head .025" which yields a 57cc combustion chamber.

[Nathan in MI]

According to Mike Shultz at Thumper, you can safely surface an E7 head .025" which yields a 57cc combustion chamber.

And in that case the compression ratio would be...?

[88grandmarq]

... higher than the stock 8.8:1

seriously, you might raise it a full point, but I doubt you would exceed 10:1

[83countrysquire]

wat heads

[88grandmarq]

wat heads

read here;

http://www.thumperoforangepark.com/

[turbo2256b]

Okay, so I'm pretty well sold on those thumper heads you suggested for my CV, but I'm wondering how they'll affect octane requirements. Will they raise compression ratio significantly so I have to run premium, or will there be something else different about the way they flow that would necessitate it?

Thanks,
Nathan

P.S. Can't wait for SF '07!

Hey how about supporting some one in the forum that ports heads. Yes you can turbo them but you have to crank the boost up some. Porting reduces back pressure so to get the same boost as non ported you have to spin the turbo faster. Turbo's are also have compressor and turbine maps to match the size of the turbo to boost pressers wanted. If you fall off the map you loose efficency or the turbo goes into surge. Non of which is good. Keeping it simple here.

[Nathan in MI]

Hey how about supporting some one in the forum that ports heads.

If you can do as good a job as the people at Thumper can with a set of E7s, I'll be more than happy to let you do the work. I'm guessing you can do it for less than the $700 it would cost me for a set of theirs, huh?

[turbo2256b]

If you can do as good a job as the people at Thumper can with a set of E7s, I'll be more than happy to let you do the work. I'm guessing you can do it for less than the $700 it would cost me for a set of theirs, huh?

We have had there heads on our bench we concider them to be better than most. We do a bit better over the whole lift range. Mrlandyaht is having a set done by us. His will run aroud 700 but that is with bigger SS valves better ssprings and retainers and locks. With stock valves ported stock retainers some better springs its around 500.
If your going turbos that needs to be addressed because other things need concidered. You should have SS valves and valve guide clearances are different Are you having your heads done or purchasing a set from them. Need to compair apples to apples here just what is in there quote to you. Conceder shipping to I am a lot closer. The shipping alone may enable partial payment or full payment of options you would like.

[Nathan in MI]

We have had there heads on our bench we concider them to be better than most. We do a bit better over the whole lift range. Mrlandyaht is having a set done by us. His will run aroud 700 but that is with bigger SS valves better ssprings and retainers and locks. With stock valves ported stock retainers some better springs its around 500.
If your going turbos that needs to be addressed because other things need concidered. You should have SS valves and valve guide clearances are different Are you having your heads done or purchasing a set from them. Need to compair apples to apples here just what is in there quote to you. Conceder shipping to I am a lot closer. The shipping alone may enable partial payment or full payment of options you would like.

If I buy a set of heads from them, it'll just be their regular ported and polished E7s, nothing fancy. The price I quoted is from their website ($595+$100 core charge).

As for the turbos, well, that project, if it ever comes to fruition, is still several years off, so I'm not too concerned about building an engine around requirements for a turbo...yet.

You do make an excellent point about shipping costs. MI to MN would be a lot cheaper than CA (they're in CA, aren't they?) to MN.

[turbo2256b]

If I buy a set of heads from them, it'll just be their regular ported and polished E7s, nothing fancy. The price I quoted is from their website ($595+$100 core charge).

As for the turbos, well, that project, if it ever comes to fruition, is still several years off, so I'm not too concerned about building an engine around requirements for a turbo...yet.

You do make an excellent point about shipping costs. MI to MN would be a lot cheaper than CA (they're in CA, aren't they?) to MN.

Kinda remember them in FLA not shure. We usally charge 100 core 500 for port with stock valves. Includes burn blast, port work, valve seat and valve work, set spring height etc. Unless it needs guide work. I have 2 sets of good E7 cores. These will flow enough air you would need a ported tunnel ram to match the flow you dont need one but upgrading the manifold will really unleash them. I can give you a list of matching componets to get the most out of them. Stock stuff will work with them. We like to have complet info on on your other mods to help you and us.

[Nathan in MI]

You do any massaging of the bowls, too, or just the ports?