4age red top

[drft_ae86]

hey guys sorry for asking so many questions..i was wondering..i have a 4age bluetop right now and wanted to raise the compression up a little bit so my question is, can i throw my 4age bluetop head onto a 4age redtop high compression block? thanks

[Ivan141]

yes, the heads can be swapped.. though the redtop head is better in stock form.

[drft_ae86]

well the only reason why i wanted to swap the head is, i was told that the red top hi comp. is front wheel drive so the intake manifold is faced the other way plus i didn't want to spend money on the adapter plate and also i wanted to use my old harness and ecu from the bluetop..sorry if im not being very clear here lol

[robokill]

just reweld the intake manifold .. many peepz done it

[oldeskewltoy]

largeport head on a small port block(or 20V block refitted with 16V high comp pistons....) works just fine. It makes good power and any mild cam will wake it up beautifully.


Advantage is NO wiring!!! Just bolt the block in and your done! Small port head will flow better, there is no doubt, but not significantly enough especially if there is an issue do to wiring, or something else butchered.

[drft_ae86]

hey oldeskewltoy, so you're saying i can do the bluetop head to the red top block? everything will fit perfectly right?

[KrizKH]

drft_ae86 Wrote:hey oldeskewltoy, so you're saying i can do the bluetop head to the red top block? everything will fit perfectly right?

Yes. But how high compression ratio do you want? are you sure the red top block is necessary?

[Ryo]

Hmm can i bother with question what compression have stock red top block compared to early (MAP) blue top block. I heard about difference between AFM and MAP bluetops so that they have difference in compression ratio but never heard of comparison early blue top and red top.

[drft_ae86]

well the stock compression on my bluetop right now is 9-1, and the red top block that i want is 10-1 so just 1 over

[Ivan141]

American bluetop : 9.4:1
Euro bluetop MAP: 10.1:1
Euro bluetop AFM: 9.4:1
Redtop: 10.4:1

Those are just some values off the top off my head, just to give you an idea of the differences, I'm sure they're not all correct.
There's no point in swapping blocks just for the added compression..but if you need to swap shortblocks anyway, why the hell not.
Stock-to-stock, I doubt the performance difference is worth it unless you go the whole hog with a MAP-conversion (and even then I think it's not worth the effort).